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  • 2020-2023  (11,265)
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  • 1
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    Structural change in coal regions as a process of economic and social-ecological transition : lessons learnt from structural change processes in Germany (2022)
    Dessau-Roßlau : Umweltbundesamt
    Details
    Publication Date: 2022-04-08
    Description: Effective policies to mitigate climate change need to be accompanied by a socially just transition. Based on experiences of past and ongoing transition policies in coal regions in Europe and with indications to the specificity of framework conditions and challenges and to the potential effectiveness and transferability of approaches, this paper presents lessons learnt which can be inspirational for similar transitions in other coal regions and for transitions in other sectors.
    Keywords: ddc:300
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: English
    Type: report , doc-type:report
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  • 2
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    Analyse des historischen Strukturwandels im Ruhrgebiet (Fallstudie) (2022)
    Dessau-Roßlau : Umweltbundesamt
    Details
    Publication Date: 2022-04-08
    Description: Diese Fallstudie untersuchte den durch die geringe Wettbewerbsfähigkeit des Steinkohlebergbaus ausgelösten Strukturwandel im Ruhrgebiet vom Ende der 1950er Jahre bis 2015. Mit Hilfe verschiedener qualitativer und quantitativer Methoden der empirischen Sozial- und Wirtschaftsforschung analysierte sie den Strukturwandelprozess und die in Reaktion auf diesen Prozess umgesetzte Strukturpolitik mit dem Ziel, dieses Wissen für zukünftige Strukturwandelprozesse in anderen (Kohle-)Regionen zur Verfügung zu stellen. Eine Diskursanalyse half zu erkennen, wer warum welche strukturpolitischen Ansätze unterstützte - und gibt damit Hinweise auf die mögliche Relevanz von Erfahrungen für andere Regionen.
    Keywords: ddc:600
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: German
    Type: report , doc-type:report
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  • 3
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    Analysis of the historical structural change in the German hard coal mining Ruhr area (case study) (2022)
    Dessau-Roßlau : Umweltbundesamt
    Details
    Publication Date: 2022-04-08
    Description: This case study examined the structural change in the Ruhr area caused by the low international competitiveness of German hard coal mining over the period from the late 1950s to 2015. It analysed the structural change process and the structural policies implemented as a reaction to this process with the objective to make this knowledge available for future structural change processes in other (coal) regions by deploying various qualitative and quantitative methods of empirical social and economic research. A discourse analysis helped to recognise who supported which structural policy approaches and why - and thus gives indications of the possible relevance of experiences for other regions.
    Keywords: ddc:600
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: English
    Type: report , doc-type:report
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  • 4
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    Analysis of the historical structural change in the German lignite mining area of Lusatia (case study) (2022)
    Dessau-Roßlau : Umweltbundesamt
    Details
    Publication Date: 2022-04-08
    Description: This case study examined the structural change in Lusatia caused by the system change from a centrally planned economy to a market economy in the period 1990-2015. It analysed the structural change process and the structural policies implemented as a reaction to this process with the objective to make this knowledge available for future structural change processes in other (coal) regions by deploying various qualitative and quantitative methods of empirical social and economic research. A discourse analysis helped to recognise who supported which structural policy approaches and why - and thus gives indications of the possible relevance of experiences for other regions.
    Keywords: ddc:300
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: English
    Type: report , doc-type:report
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  • 5
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    Analyse des historischen Strukturwandels in der Lausitz (Fallstudie) (2022)
    Dessau-Roßlau : Umweltbundesamt
    Details
    Publication Date: 2022-04-08
    Description: Diese Fallstudie untersuchte den durch den Systemwechsel von der Plan- zur Marktwirtschaft ausgelösten Strukturwandel in der Lausitz im Zeitraum 1990-2015. Mit Hilfe verschiedener qualitativer und quantitativer Methoden der empirischen Sozial- und Wirtschaftsforschung analysierte sie den Strukturwandelprozess und die in Reaktion auf diesen Prozess umgesetzte Strukturpolitik mit dem Ziel, dieses Wissen für zukünftige Strukturwandelprozesse in anderen (Kohle-)Regionen zur Verfügung zu stellen. Eine Diskursanalyse half zu erkennen, wer warum welche strukturpolitischen Ansätze unterstützte - und gibt damit Hinweise auf die mögliche Relevanz von Erfahrungen für andere Regionen.
    Keywords: ddc:600
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: German
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  • 6
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    High-Resolution Snow Depth on Arctic Sea Ice From Low-Altitude Airborne Microwave Radar Data (2021)
    IEEE
    In:  EPIC3IEEE Transactions on Geoscience and Remote Sensing, IEEE, (60), pp. 1-16, ISSN: 0196-2892
    Details
    Publication Date: 2022-04-08
    Description: We present new high-resolution snow depth data on Arctic sea ice derived from airborne microwave radar measurements from the IceBird campaigns of the Alfred Wegener Institute (AWI) together with a new retrieval method using signal peakiness based on an intercomparison exercise of colocated data at different altitudes. We aim to demonstrate the capabilities and potential improvements of radar data, which were acquired at a lower altitude (200 ft) and slower speed (110 kn) and had a smaller radar footprint size (2-m diameter) than previous airborne snow radar data. So far, AWI Snow Radar data have been derived using a 2-18-GHz ultrawideband frequency-modulated continuous-wave (FMCW) radar in 2017-2019. Our results show that our method in combination with thorough calibration through coherent noise removal and system response deconvolution significantly improves the quality of the radar-derived snow depth data. The validation against a 2-D grid of in situ snow depth measurements on level landfast first-year ice indicates a mean bias of only 0.86 cm between radar and ground truth. Comparison between the radar-derived snow depth estimates from different altitudes shows good consistency. We conclude that the AWI Snow Radar aboard the IceBird campaigns is able to measure the snow depth on Arctic sea ice accurately at higher spatial resolution than but consistent with the existing airborne snow radar data of NASA Operation IceBridge. Together with the simultaneous measurements of the total ice thickness and surface freeboard, the IceBird campaign data will be able to describe the whole sea-ice column on regional scales.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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  • 7
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    Sustainable fish feeds: potential of emerging protein sources in diets for juvenile turbot (Scophthalmus maximus) in RAS (2022)
    In:  EPIC3Aquaculture International, ISSN: 0967-6120
    Details
    Publication Date: 2022-04-08
    Description: In Europe, turbot aquaculture has a high potential for sustainable production, but the low tolerance to fishmeal replacement in the diet represents a big issue. Therefore, this study investigated the effects of more sustainable feed formulations on growth and feed performance, as well as nutritional status of juvenile turbot in recirculating aquaculture systems. In a 16-week feeding trial with 20 g juvenile turbot, one control diet containing traditional fishmeal, fish oil and soy products and two experimental diets where 20% of the fishmeal was replaced either with processed animal proteins (PAP) or with terrestrial plant proteins (PLANT) were tested. Irrespective of diets, growth performance was similar between groups, whereas the feed performance was significantly reduced in fish of the PAP group compared to the control. Comparing growth, feed utilisation and biochemical parameters, the results indicate that the fish fed on PAP diet had the lowest performance. Fish fed the PLANT diet had similar feed utilisation compared to the control, whereas parameters of the nutritional status, such as condition factor, hepato-somatic index and glycogen content showed reduced levels after 16 weeks. These effects in biochemical parameters are within the physiological range and therefore not the cause of negative performance. Since growth was unaffected, the lower feed performance of fish that were fed the PAP formulation might be balanced by the cost efficient formulation in comparison to the commercial and the PLANT formulations. Present study highlights the suitability of alternative food formulation for farmed fish.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev , info:eu-repo/semantics/article
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  • 8
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    Analyse par CPG des acides gras des algues marines Cystoseira sauvageauana et Laurencia pinnatifida (2022)
    Details
    Publication Date: 2022-04-08
    Description: Les algues comportent des substances naturelles très prometteuses, exploitables pour la nutrition humaine, l’industrie pharmaceutique et agroalimentaire. L’Algérie possède près de 1600 km de côte, renfermant une diversité algale considérable. Une telle diversité, sousexploitée, constitue un réel potentiel pour la recherche et l’industrie. Dans la présente étude, l’accent sera mis sur la composition chimique en acides gras des algues marines Cystoseira sauvageauana et Laurencia pinnatifida collectées dans la région côtière de Tipasa. Le profil en acides gras des algues a été déterminé après avoir effectué une extraction des lipides suivie d’une estérification des acides gras et caractérisation de ces derniers par chromatographie en phase gazeuse (CPG).Les acides gras identifiés chez les deux espèces étudiées varient du C14 à C20, l'acide palmitique (C16:0) étant le composé majoritaire. En outre, l’acide arachidonique (C20:4) et l’acide eicosapentaénoïque EPA (C20:5) constituent les principaux acides gras polyinsaturés (AGPI).
    Description: Algae contain very promising natural substances that can be used for human nutrition, the pharmaceutical industry and food processing. Algeria has nearly 1600 km of coastline, containing a considerable algal diversity. Such diversity, which is under-exploited, constitutes a real potential for research and industry. This study will focus on the chemical composition of fatty acids of the marine algae Cystoseira sauvageauana and Laurencia pinnatifida collected in the coastal region of Tipaza. The fatty acid profile of the algae was determined after performing lipid extraction followed by esterification of the fatty acids and characterization of the latter by gas chromatography (GC). The fatty acids identified in the two species studied range from C14 to C20, with palmitic acid (C16:0) being the major compound. In addition, arachidonic acid (C20:4) and eicosapentaenoic acid EPA (C20:5) are the main polyunsaturated fatty acids (PUFA).
    Description: Published
    Description: Refereed
    Keywords: Chemical composition ; Laurencia pinnatifida ; Fatty acids ; Algal diversity ; Food processing ; Acides gras polyinsaturés (AGPI) ; Cystoseira sauvageauan ; Acide arachidonique ; Acide eicosapentaénoïque ; Acide palmitique ; Eicosapentaenoic acid ; Palmitic acid ; Arachidonic acid ; ASFA_2015::P::Polyunsaturated fatty acids ; ASFA_2015::G::Gas chromatography ; ASFA_2015::B::Botanical resources
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.4-9
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  • 9
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    About terraces on the shore of the Teriberskaya Bay of the Barents Sea (the Kola Peninsula) (2022)
    Details
    Publication Date: 2022-04-08
    Description: The paper considers the results of the study of modern terraces on the coast of the Lodeyny Peninsula in the Barents Sea. According to field observations, decoding of space and geodetic maps and volumetric modeling, signs of three terraces have been identified. Two terraces having a rear seam, a cliff, a brow and horizontal platforms have been studied in more detail. The rear seams are located at 7 and 30 m, and the edges at 10 and 40 m above the sea level. The third terrace is confined to the level of 40–60 m, and has not been studied in detail. According to estimates, the first two terraces were formed about 3,300 and 6,000 years ago respectively. The 1st terrace characterizes the period of slow land rise by 10 m, at the speed up to 3 mm/year, which began about 3,300 years ago and continues to the present. It is characterized by a uniform sea retreat of about 15 mm/year. The erosion products of this terrace are common in the lateral zone and represent modern marine sediments, including beaches forming a new terrace. The 2nd terrace characterizes to the dynamics of rapid land rise by 30 m at a speed of about 11 mm/year, which occurred in the period from 6,000 to 3,300 years ago. The erosion products of this terrace are most common on the coast and are found at a distance of 100 m to 2–3 km from the shore. It is assumed that the speed of movement of the coastline during the retreat of the sea was different and reached up to 900 mm/year. According to the authors, preliminary data indicate the instability of the territory and the manifestation of block movements, which may have a negative impact on the development of infrastructure.
    Description: В статье рассмотрены результаты изучения современных террас на побережье Баренцева моря в районе п-ва Лодейный. По данным натурных наблюдений, дешифрирования космических и геодезических карт и объемного моделирования выявлены признаки трех террас. Более детально изучены две террасы, у которых присутствуют тыловой шов, обрыв, бровка и горизонтальные площадки. Тыловые швы располагаются на отметках 7 и 30 м, а бровки – на отметках 10 и 40 м над уровнем моря. Третья терраса приурочена к уровню 40–60 м, детально не изучена. По расчетным данным первые две террасы образовались около 3 300 и 6 000 лет назад. 1-я терраса характеризует период медленного подъема суши на 10 м со скоростью около 3 мм/год, начавшийся около 3 300 лет назад и продолжающийся по настоящее время. Продукты размыва этой террасы распространены в латеральной зоне и представляют современные морские отложения, в том числе пляжи, формирующие новую террасу. 2-я терраса характеризует динамику быстрого подъема суши на 30 м со скоростью около 11 мм/год, произошедшего в период от 6 000 до 3 300 лет назад. Продукты размыва этой террасы имеют наибольшее распространение на побережье и встречаются на расстоянии от 100 м до 2–3 км от берега. Предполагается, что скорость перемещения береговой линии при отступлении моря была различной и достигала до 900 мм/год. По мнению авторов, предварительные данные свидетельствуют о нестабильности территории и проявлении блоковых подвижек, что может оказать негативное воздействие на развитие инфраструктуры.
    Description: Published
    Description: Refereed
    Keywords: Arctic coast ; Transformation of the shores ; Арктическое побережье ; Tрансформация берегов ; ASFA_2015::T::Terraces ; ASFA_2015::A::Arctic zone ; ASFA_2015::A::Arctic waters ; ASFA_2015::B::Bays ; ASFA_2015::B::Beach cusps ; ASFA_2015::B::Beach features
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.38-49
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  • 10
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    Editorial: Geochemical Signals in Dynamic Sedimentary Systems Along Continental Margins (2022)
    In:  EPIC3Frontiers in Earth Science
    Details
    Publication Date: 2022-04-12
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , notRev
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  • 11
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    Late Quaternary glacier and sea‐ice history of northern Wijdefjorden, Svalbard (2020)
    In:  EPIC3Boreas, 49(3), pp. 417-437, ISSN: 0300-9483
    Details
    Publication Date: 2022-04-12
    Description: The deglaciation history and Holocene environmental evolution of northern Wijdefjorden, Svalbard, are reconstructed using sediment cores and acoustic data (multibeam swath bathymetry and sub-bottom profiler data). Results reveal that the fjord mouth was deglaciated prior to 14.5±0.3 cal. ka BP and deglaciation occurred stepwise. Biomarker analyses show rapid variations in water temperature and sea ice cover during the deglaciation, and cold conditions during the Younger Dryas, followed by minimum sea ice cover throughout the Early Holocene, until c. 7 cal. ka BP. Most of the glaciers in Wijdefjorden had retreated onto land by c. 7.6±0.2 cal. ka BP. Subsequently, the sea-ice extent increased and remained high throughout the last part of the Holocene. We interpret a high Late Holocene sediment accumulation rate in the northernmost core to reflect increased sediment flux to the site from the outlet of the adjacent lake Femmilsjøen, related to glacier growth in the Femmilsjøen catchment area. Furthermore, increased sea ice cover, lower water temperatures and the re-occurrence of ice-rafted debris indicate increased local glacier activity and overall cooler conditions in Wijdefjorden after c. 0.5 cal. ka BP. We summarize our findings in a conceptual model for the depositional environment in northern Wijdefjorden from the Late Weichselian until present.
    Repository Name: EPIC Alfred Wegener Institut
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  • 12
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    Pleistocene depositional environments and links to cryosphere-ocean interactions on the eastern Ross Sea continental slope, Antarctica (IODP Hole U1525A) (2022)
    In:  EPIC3Marine Geology, 443, pp. 106674, ISSN: 00253227
    Details
    Publication Date: 2022-04-12
    Description: The repeated proximity of West Antarctic Ice Sheet (WAIS) ice to the eastern Ross Sea continental shelf break during past ice age cycles has been inferred to directly influence sedimentary processes occurring on the continental slope, such as turbidity current and debris flow activity; thus, the records of these processes can be used to study the past history of the WAIS. Ross Sea slope sediments may additionally provide an archive on the history and interplay of density-driven or geostrophic oceanic bottom currents with ice-sheet-driven depositional mechanisms. We investigate the upper 121 m of Hole U1525A, collected during International Ocean Discovery Program (IODP) Expedition 374 in 2018. Hole U1525A is located on the southwestern external levee of the Hillary Canyon (Ross Sea, Antarctica) and the depositional lobe of the nearby trough-mouth fan. Using core descriptions, grain size analysis, and physical properties datasets, we develop a lithofacies scheme that allows construction of a detailed depositional model and environmental history of past ice sheet-ocean interactions at the eastern Ross Sea continental shelf break/slope since ~2.4 Ma. The earliest Pleistocene interval (~2.4- ~ 1.4 Ma) represents a hemipelagic environment dominated by ice-rafting and reworking/deposition by relatively persistent bottom current activity. Finely interlaminated silty muds with ice-rafted debris (IRD) layers are interpreted as contourites. Between ~1.4 and ~0.8 Ma, geostrophic bottom current activity was weaker and turbiditic processes more common, likely related to the increased proximity of grounded ice at the shelf edge. Silty, normally-graded laminations with sharp bases may be the result of flow-stripped turbidity currents overbanking the canyon levee during periods when ice was grounded at or proximal to the shelf edge. A sandy, IRD- and foraminifera-bearing interval dated to ~1.18 Ma potentially reflects warmer oceanographic conditions and a period of stronger Antarctic Slope Current flow. This may have enhanced upwelling of warm Circumpolar Deep Water onto the shelf, leading to large-scale glacial retreat at that time. The thickest interval of turbidite interlamination was deposited after ~1 Ma, following the onset of the Mid-Pleistocene Transition, interpreted as a time when most ice sheets grew and glacial periods were longer and more extreme. Sedimentation after ~0.8 Ma was dominated by glacigenic debris flow deposition, as the trough mouth fan that dominates the eastern Ross Sea continental slope prograded and expanded over the site. These findings will help to improve estimations of WAIS ice extent in future Ross Sea shelf-based modelling studies, and provide a basis for more detailed analysis of the inception and growth of the WAIS under distinct oceanographic conditions.
    Repository Name: EPIC Alfred Wegener Institut
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  • 13
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    Archaeal intact polar lipids in polar waters: a comparison between the Amundsen and Scotia seas (2021)
    In:  EPIC3Biogeosciences, 18(11), pp. 3485-3504, ISSN: 1726-4189
    Details
    Publication Date: 2022-04-12
    Description: The West Antarctic Ice Sheet (WAIS) is one of the largest potential sources of future sea-level rise, with glaciers draining the WAIS thinning at an accelerating rate over the past 40 years. Due to complexities in calibrating palaeoceanographic proxies for the Southern Ocean, it remains difficult to assess whether similar changes have occurred earlier during the Holocene or whether there is underlying centennial- to millennial-scale forcing in oceanic variability. Archaeal lipid-based proxies, specifically glycerol dialkyl glycerol tetraether (GDGT; e.g. TEX86 and TEXL86), are powerful tools for reconstructing ocean temperature, but these proxies have been shown previously to be difficult to apply to the Southern Ocean. A greater understanding of the parameters that control Southern Ocean GDGT distributions would improve the application of these biomarker proxies and thus help provide a longer-term perspective on ocean forcing of Antarctic ice sheet changes. In this study, we characterised intact polar lipid (IPL)-GDGTs, representing (recently) living archaeal populations in suspended particulate matter (SPM) from the Amundsen Sea and the Scotia Sea. SPM samples from the Amundsen Sea were collected from up to four water column depths representing the surface waters through to Circumpolar Deep Water (CDW), whereas the Scotia Sea samples were collected along a transect encompassing the sub-Antarctic front through to the southern boundary of the Antarctic Circumpolar Current. IPL-GDGTs with low cyclic diversity were detected throughout the water column with high relative abundances of hydroxylated IPL-GDGTs identified in both the Amundsen and Scotia seas. Results from the Scotia Sea show shifts in IPL-GDGT signatures across well-defined fronts of the Southern Ocean. Indicating that the physicochemical parameters of these water masses determine changes in IPL-GDGT distributions. The Amundsen Sea results identified GDGTs with hexose-phosphohexose head groups in the CDW, suggesting active GDGT synthesis at these depths. These results suggest that GDGTs synthesised at CDW depths may be a significant source of GDGTs exported to the sedimentary record and that temperature reconstructions based on TEX86 or TEXL86 proxies may be significantly influenced by the warmer waters of the CDW.
    Repository Name: EPIC Alfred Wegener Institut
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  • 14
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    Trackline map and processing report for navigation sensors from Heincke HE593 (2022)
    Alfred Wegener Institute
    In:  EPIC3Bremerhaven, Alfred Wegener Institute
    Details
    Publication Date: 2022-04-12
    Repository Name: EPIC Alfred Wegener Institut
    Type: Data Processing Reports , notRev
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  • 15
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    Trackline map and processing report for navigation sensors from Heincke HE594 (2022)
    Alfred Wegener Institute
    In:  EPIC3Bremerhaven, Alfred Wegener Institute
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    Publication Date: 2022-04-12
    Repository Name: EPIC Alfred Wegener Institut
    Type: Data Processing Reports , notRev
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  • 16
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    Bottom current control on sediment deposition between the Iselin Bank and the Hillary Canyon (Antarctica) since the late Miocene: An integrated seismic-oceanographic approach (2021)
    In:  EPIC3Deep Sea Research Part I: Oceanographic Research Papers, 176, pp. 103606, ISSN: 09670637
    Details
    Publication Date: 2022-04-12
    Description: In this paper we analyze how oceanic circulation affects sediment deposition along a sector of the Ross Sea continental margin, between the Iselin Bank and the Hillary Canyon, and how these processes evolved since the Late Miocene. The Hillary Canyon is one of the few places around the Antarctic continental margin where the dense waters produced onto the continental shelf, mainly through brine rejection related to sea ice production, flow down the continental slope and reach the deep oceanic bottom layer. At the same time the Hillary Canyon represents a pathway for relatively warm waters, normally flowing along the continental slope within the Antarctic Slope Current, to reach the continental shelf. The intrusion of warm waters onto the continental shelf produces basal melting of the ice shelves, reduces their buttressing effect and triggers instabilities of the ice sheet that represent one of the main uncertainties in future sea level projections. For this study we use seismic, morpho-bathymetric and oceanographic data acquired in 2017 by the R/V OGS Explora. Seismic profiles and multibeam bathymetry are interpreted together with age models from two drilling sites (U1523 and U1524) of the International Ocean Discovery Program (IODP) Expedition 374. Oceanographic data, together with a regional oceanographic model, are used to support our reconstruction by showing the present-day oceanographic influence on sediment deposition. Regional correlation of the main seismic unconformities allows us to identify eight seismic sequences. Seismic profiles and multibeam bathymetry show a strong influence of bottom current activity on sediment deposition since the Early Miocene and a reduction in their intensity during the mid-Pliocene Warm Period. Oceanographic data and modelling provide evidence that the bottom currents are related to the dense waters produced on the Ross Sea continental shelf and flowing out through the Hillary Canyon. The presence of extensive mass transport deposits and detachment scarps indicate that also mass wasting participates in sediment transport. Through this integrated approach we regard the area between the Iselin Bank and the Hillary Canyon as a Contourite Depositional System (ODYSSEA CDS) that offers a record of oceanographic and sedimentary conditions in a unique setting. The hypotheses presented in this work are intended to serve as a framework for future reconstructions based on detailed integration of lithological, paleontological, geochemical and petrophysical data.
    Repository Name: EPIC Alfred Wegener Institut
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  • 17
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    Dispersal, location of bloom initiation, and nutrient conditions determine the dominance of the harmful dinoflagellate Alexandrium catenella: A meta‐ecosystem study (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-04
    Description: Harmful algal blooms (HABs) are globally increasing in number and spatial extent. However, their propagation dynamics along environmental gradients and the associated interplay of abiotic factors and biotic interactions are still poorly understood. In this study, a nutrient gradient was established in a linear meta‐ecosystem setup of five interconnected flasks containing an artificially assembled phytoplankton community. The harmful dinoflagellate Alexandrium catenella was introduced into different positions along the nutrient gradient to investigate dispersal and spatial community dynamics. Overall, total algal biovolume increased, while community evenness decreased with increasing nutrient concentrations along the gradient. Alexandrium was able to disperse through all flasks. On the regional scale, diatoms dominated the community, whereas on the local scale the dinoflagellate showed higher contributions at low nutrient concentrations and dominated the community at the lowest nutrient concentration, but only when initiated into this flask. A control treatment without dispersal revealed an even stronger dominance of Alexandrium at the lowest nutrient concentration, indicating that dispersal and the associated nutrient exchange may weaken dinoflagellate dominance under low nutrient conditions. This study presents a first approach to experimentally investigate spatial dynamics and ecological interactions of a harmful dinoflagellate along an environmental gradient in a meta‐ecosystem setup, which has the potential to substantially enhance our understanding of the relevance of dispersal for HAB formation and propagation in combination with local environmental factors.
    Description: Volkswagen Foundation http://dx.doi.org/10.13039/501100001663
    Keywords: ddc:579 ; ddc:550.724
    Language: English
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    Seasonal Differences in the Attenuation of Polar Trace Organics in the Hyporheic Zone of an Urban Stream (2022)
    Details
    Publication Date: 2022-04-04
    Description: Attenuation of trace organic compounds (TrOCs) in a river occurs to a large extent in its hyporheic zone. A major part of the attenuation of polar TrOCs is of microbial origin. As microbial activity depends on temperature and redox conditions, seasonal differences in TrOC attenuation are likely. We investigated TrOC attenuation at a river influenced by treated wastewater during two sampling campaigns, one in summer and one in winter. In addition to redox conditions and temperature, we also determined residence times of porewater in sediment using three methods: (a) non‐parametric deconvolution of electrical conductivity time series, (b) the model VFLUX 2.0 based on temperature time series (only summer), and (c) applying Darcy's law to differences in hydraulic heads (only summer). Contrary to our expectations, we found higher attenuation for 12 out of 18 TrOCs in winter, while three TrOCs were better attenuated in summer. Sediment conditions varied between seasons as more of the top sandy layer with a higher hydraulic permeability accumulated on the river bed in summer. As a result, residence times in the sediment were shorter in summer. In winter, longer residence times, lower temperatures, and a steeper oxygen gradient in sediment coincided with higher TrOC attenuation. Further research is needed to understand our unexpected findings and underlying mechanisms.
    Description: Key Points: The attenuation of 12 out of 18 trace organic compounds (TrOCs) in the hyporheic zone was higher in winter while three TrOCs were attenuated better in summer. Residence times in sediment were longer and more diverse in winter. The extent of the oxic sediment was similar between seasons but the gradient from the oxic to anoxic zone was steeper in winter.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: EC | H2020 | H2020 Priority Excellent Science | H2020 Marie Skłodowska‐Curie Actions (MSCA) http://dx.doi.org/10.13039/100010665
    Description: University of Western Australia ‐ University Postgraduate Award
    Description: Australian Government Research Training Program Scholarship
    Description: Bundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347
    Description: https://doi.org/10.18728/igb-fred-578.0
    Keywords: ddc:628.162
    Language: English
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    Comparison of Denitrification Induced by Various Organic Substances—Reaction Rates, Microbiology, and Temperature Effect (2021)
    Details
    Publication Date: 2022-04-04
    Description: Widespread groundwater pollution with nitrate (NO3−) and the finite and decreasing geogenic NO3− degradation capacity in aquifers require a better understanding of potential treatment methods. This project aimed at exploring and comparing the efficiency of four organic substances as electron donors for heterotrophic denitrification. Circulation column experiments using sediment without NO3− degradation capacity and high agricultural NO3− groundwater were conducted. Acetate, glucose, ascorbic acid, and ethanol were added to these columns in three concentration steps to induce biological denitrification, whereby also temperature dependence of denitrification rates (room temperature and typical groundwater temperature of 10°C) was taken into account. Results show denitrification with all four carbon (C) sources with intensities varying considerably between electron donors. Comparison of the two temperature approaches shows substantial differences between applied organic substances and indicates T as an important variable for denitrification. Ethanol is clearly the most effective electron donor for biodenitrification in groundwater investigated in this study, with a stronger and more effective NO3− degradation at 10°C than at room temperature. In contrast, much higher reaction rates are achieved with glucose at room temperature, compared to 10°C. Denitrification with ascorbic acid is very low at both temperatures; its addition produces biomass which repeatedly led to column clogging. In the entire test series, nitrite (NO2−) accumulation occurred more frequently and in higher concentrations at 10°C. Analysis of microorganisms shows a strong modification in microbial community in reaction to the addition of different organic C as well as between the two temperature approaches.
    Description: Key Points: Higher denitrification rate with ethanol at 10°C, consequently, reaction kinetics does not generally increase with rising temperature. Addition of organic substances and temperature strongly modify the denitrifying microbial community. Electron donor selection for induced nitrate reduction depends on the groundwater temperature of the region.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Keywords: ddc:553.79 ; ddc:550.724 ; ddc:628.162
    Language: English
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    Nitrogen and Phosphorus Control Soil Methane Uptake in Tropical Montane Forests (2021)
    Details
    Publication Date: 2022-04-04
    Description: Tropical forests contribute about one third to global annual CH4 uptake by soils. Understanding the factors that control the soil‐atmosphere exchange of CH4 at a large scale is a critical step to improve the CH4 flux estimate for tropical soils, which is presently poorly constrained. Since tropical forest degradation often involves shifts in nutrient availabilities, it is critical to evaluate how this will affect soil CH4 flux. Here, we report how nitrogen (N; 50 kg N ha−1 yr−1), phosphorus (P; 10 kg P ha−1 yr−1), and combined N + P additions affect soil CH4 fluxes across an elevation gradient of tropical montane forests. We measured soil CH4 fluxes in a nutrient application experiment at different elevations over a period of 5 years. Nutrient additions increased soil CH4 uptake after 4–5 years of treatment but effects were not uniform across elevations. At 1,000 m, where total soil P was high, we detected mainly N limitation of soil CH4 uptake. At 2,000 m, where total soil P was low, a strong P limitation of soil CH4 uptake was observed. At 3,000 m, where total P was low in the organic layer but high in mineral soil, we found N limitation of soil CH4 uptake. Our results show that projected increases of N and P depositions may increase soil CH4 uptake in tropical montane forests but the direction, magnitude, and timing of the effects will depend on forests' nutrient status and plant‐microbial competition for N and P.
    Description: Plain Language Summary: CH4 is a potent greenhouse gas that contributes to global warming. Tropical forests are a natural sink of CH4 but increasing nutrient depositions due to industrialization may alter the sink strength of tropical forests. Our results show that projected increases of nitrogen and phosphorus depositions may increase soil CH4 uptake in tropical montane forests but the direction, magnitude, and timing of the effects will depend on forests' nutrients and plant‐microbial competition.
    Description: Key Points: Projected increases in nitrogen and phosphorus depositions in the tropics will stimulate soil methane uptake in tropical montane forests. The direction, magnitude, and timing of nutrient deposition effects on soil methane uptake will depend on forests' nutrient status. Nutrient limitations on ecosystem processes have to be investigated in actual field conditions.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: https://doi.org/10.25625/XLNKNK
    Keywords: ddc:551.9 ; ddc:631.41
    Language: English
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    ‘Ten Years After’—a long‐term settlement and bioerosion experiment in an Arctic rhodolith bed (Mosselbukta, Svalbard) (2021)
    Details
    Publication Date: 2022-04-04
    Description: Rhodolith beds and bioherms formed by ecosystem engineering crustose coralline algae support the northernmost centres of carbonate production, referred to as polar cold‐water carbonate factories. Yet, little is known about biodiversity and recruitment of these hard‐bottom communities or the bioeroders degrading them, and there is a demand for carbonate budgets to include respective rates of polar carbonate build‐up and bioerosion. To address these issues, a 10‐year settlement and bioerosion experiment was carried out at the Arctic Svalbard archipelago in and downslope of a rhodolith bed. The calcifiers recorded on experimental settlement tiles (56 taxa) were dominated by bryozoans, serpulids and foraminiferans. The majority of the bioerosion traces (30 ichnotaxa) were microborings, followed by attachment etchings and grazing traces. Biodiversity metrics show that calcifier diversity and bioerosion ichnodiversity are both elevated in the rhodolith bed, if compared to adjacent aphotic waters, but these differences are statistically insignificant. Accordingly, there were only low to moderate dissimilarities in the calcifier community structure and bioerosion trace assemblages between the two depth stations (46 and 127 m), substrate orientations (up‐ and down‐facing) and substrate types (PVC and limestone), in that order of relevance. In contrast, surface coverage as well as the carbonate accretion and bioerosion rates were all significantly elevated in the rhodolith bed, reflecting higher abundance or size of calcifiers and bioerosion traces. All three measures were highest for up‐facing substrates at 46 m, with a mean coverage of 78.2% (on PVC substrates), a mean accretion rate of 24.6 g m−2  year−1 (PVC), and a mean bioerosion rate of −35.1 g m−2 year−1 (limestone). Differences in these metrics depend on the same order of factors than the community structure. Considering all limestone substrates of the two platforms, carbonate accretion and bioerosion were nearly in balance at a net rate of −2.5 g m−2 year−1. A latitudinal comparison with previous settlement studies in the North Atlantic suggests that despite the harsh polar environment there is neither a depletion in the diversity of hard‐bottom calcifier communities nor in the ichnodiversity of grazing traces, attachment etchings and microborings formed by organotrophs. In contrast, microborings produced by phototrophs are strongly depleted because of limitations in the availability of light (condensed photic zonation, polar night, shading by sea ice). Also, macroborings were almost absent, surprisingly. With respect to carbonate production, the Svalbard carbonate factory marks the low end of a latitudinal gradient while bioerosion rates are similar or even higher than at comparable depth or photic regime at lower latitudes, although this might not apply to shallow euphotic waters (not covered in our experiment), given the observed depletion in bioeroding microphytes and macroborers. While echinoid grazing is particularly relevant for the bioerosion in the rhodolith bed, respective rates are far lower than those reported from tropical shallow‐water coral reefs. The slow pace of carbonate production but relatively high rates of bioerosion (both promoted by low carbonate supersaturation states in Arctic waters), in concert with high retention of skeletal carbonates on the seafloor and no calcite cements forming in open pore space created by microborers, suggest a low fossilisation potential for polar carbonates, such as those formed in the Mosselbukta rhodolith beds.
    Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659
    Keywords: ddc:593.6 ; ddc:528.58
    Language: English
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    Focused methane migration formed pipe structures in permeable sandstones: Insights from uncrewed aerial vehicle‐based digital outcrop analysis in Varna, Bulgaria (2021)
    Details
    Publication Date: 2022-04-04
    Description: Focused fluid flow shapes the evolution of marine sedimentary basins by transferring fluids and pressure across geological formations. Vertical fluid conduits may form where localized overpressure breaches a cap rock (permeability barrier) and thereby transports overpressured fluids towards shallower reservoirs or the surface. Field outcrops of an Eocene fluid flow system at Pobiti Kamani and Beloslav Quarry (ca 15 km west of Varna, Bulgaria) reveal large carbonate‐cemented conduits, which formed in highly permeable, unconsolidated, marine sands of the northern Tethys Margin. An uncrewed aerial vehicle with an RGB sensor camera produces ortho‐rectified image mosaics, digital elevation models and point clouds of the two kilometre‐scale outcrop areas. Based on these data, geological field observations and petrological analysis of rock/core samples, fractures and vertical fluid conduits were mapped and analyzed with centimetre accuracy. The results show that both outcrops comprise several hundred carbonate‐cemented fluid conduits (pipes), oriented perpendicular to bedding, and at least seven bedding‐parallel calcite cemented interbeds which differ from the hosting sand formation only by their increased amount of cementation. The observations show that carbonate precipitation likely initiated around areas of focused fluid flow, where methane entered the formation from the underlying fractured subsurface. These first carbonates formed the outer walls of the pipes and continued to grow inward, leading to self‐sustaining and self‐reinforcing focused fluid flow. The results, supported by literature‐based carbon and oxygen isotope analyses of the carbonates, indicate that ambient seawater and advected fresh/brackish water were involved in the carbonate precipitation by microbial methane oxidation. Similar structures may also form in modern settings where focused fluid flow advects fluids into overlying sand‐dominated formations, which has wide implications for the understanding of how focusing of fluids works in sedimentary basins with broad consequences for the migration of water, oil and gas.
    Description: Integrated School of Ocean Sciences (ISOS) Kiel
    Description: European Union’s Horizon 2020 http://dx.doi.org/10.13039/100010661
    Description: Bulgarian Science Fund
    Keywords: ddc:551
    Language: English
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    The Impact of Typhoon “Mangkhut” on Surface Water Nutrient and Chlorophyll Inventories of the South China Sea in September 2018 (2021)
    Details
    Publication Date: 2022-04-04
    Description: The influence of the exceptionally strong typhoon Mangkhut on the availability of nutrients and changes in primary production were studied in the northern South China Sea in September 2018. A tight station grid was sampled to analyze major nutrients, chlorophyll_a, particulate and dissolved organic carbon and nitrogen. Based on interpolated profiles, nutrients and organic matter budgets were determined for the upper 100 m of the water column prior to and after Mangkhut's passage. An upper layer of 100 m was found to reflect the important changes by the typhoon. Considerable differences between the on‐shelf, shelf edge and the deep‐sea stations were determined. Nitrate and phosphate increased by about 80% and 36% on the shelf, respectively, and both by almost 40% at the shelf edge. The open deep‐sea part of the study area reflects some deviating results that may be caused by just displacement of water or by mixing water of different origin. However, right on Mangkhut's track on the shelf even contact between surface waters and bottom waters was enabled, increasing phosphate and silicate, but declining nitrate. The inventory of organic carbon of the upper 100 m of the study area (138,000 km2) of 92 Gmol had increased within a few days after the typhoon's passage by 5 Gmol on the shelf and about 2 Gmol in the shelf edge area. Chlorophyll_a doubled during our stay and might have reached a factor of 3 increase in the subsequent time by nitrate supply and excess phosphate.
    Description: Plain Language Summary: The influence of the super typhoon Mangkhut on the waters of the northern South China Sea was studied in September 2018. Nutrients and organic material were measured on 63 stations from the Chinese research vessel HAI YANG DI ZHI SHI HAO. Amounts of nutrients and biogenic matter were calculated for the on‐shelf, shelf edge and deep‐sea stations for the pre‐ and post‐Mangkhut period. An important finding was that the stations of the different areas, on‐shelf, shelf edge and the deep‐sea appeared to be differently impacted by Mangkhut. Even differences between the stations right on its track and in the other parts of the study area were found. In general, nutrients were supplied in enormous amounts and caused immediate algae growth. Moreover, enough nutrients were supplied to support algae growth for a couple of weeks. In summary, it was found that Manghut's upper water column mixing and shifting caused an almost tripling of primary production compared to the normal situation.
    Description: Key Points: The typhoon Mangkhut clearly impacted the water column differently on the continental shelf, at the shelf edge and in the deep sea. On Mangkhut's track a maximum nitrate supply of 162 mmol m−2 was caused by induced upwelling at the shelf edge. The chlorophyll inventory of 2.8 Gg was almost tripled by contributing 4.7 Gg estimated from an additional nutrient supply.
    Description: Federal Ministry of Education and Research, BMBF http://dx.doi.org/10.13039/501100002347
    Description: National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809
    Description: https://doi.pangaea.de/10.1594/PANGAEA.936352
    Description: https://doi.pangaea.de/10.1594/PANGAEA.936096
    Keywords: ddc:577.7
    Language: English
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    Iron Exports From Catchments Are Constrained by Redox Status and Topography (2022)
    Details
    Publication Date: 2022-04-04
    Description: Fe(III) hydroxides stabilize organic carbon (OC) and P in soils. Observations of rising stream Fe concentrations are controversially posited to result from a flushing of iron‐rich deeper soil layers or a decrease of competing electron acceptors inhibiting Fe reduction (NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ and SO42− $\mathrm{S}{{\mathrm{O}}_{4}}^{2-}$). Here, we argue that catchment topography constrains the release of Fe, OC, and P to streams. We therefore incubated organic topsoil and mineral subsoil and modified the availability of NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$. We found that Fe leaching was highest in topsoil. Fe, OC, and P released at quantities proportional to their ratios in the source soil. Supply of NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ reduced Fe leaching to 18% and increased pore water OC:Fe and P:Fe ratios. Subsoil, however, was an insignificant Fe source (〈0.5%). Here, the leached quantities of Fe, OC and P were highly disproportionate to the soil source with an excess of released OC and P. We tested if experimental findings scale up using data from 88 German catchments representing gradients in NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ concentration and topography. Average stream Fe concentrations increased with decreasing NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ and were high in catchments with shallow topography where high groundwater levels support reductive processes and topsoils are hydrologically connected to streams; but Fe concentrations were low in catchments with steep topography where flow occurs primarily through subsoils. OC:Fe and P:Fe ratios in the streams similarly varied by NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ and topography. This corroborates the findings from the laboratory experiment and suggests that catchment topography and competing electron acceptors constrain the formation of Fe‐reducing conditions and control the release of Fe, OC, and P to streams.
    Description: Plain Language Summary: Iron is the second most abundant metal in the crust; its cycle is tightly connected to those of carbon, oxygen, and sulfur. The oxidized form (FeIII) is almost insoluble, but Fe can be mobilized by complexation or microbial Fe reduction. Both processes depend on availability of organic C. We found that Fe concentrations in streams were constrained by the topography of catchments and NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ abundance. Shallower catchments are characterized by higher groundwater tables connecting the organic topsoils efficiently to streams. NO3− $\mathrm{N}{{\mathrm{O}}_{3}}^{-}$ suppresses Fe reduction as a competing electron acceptor to Fe. We conclude that trends in soil wetness or atmospheric N deposition can change the stability of Fe and thus the release of PO43− $\mathrm{P}{{\mathrm{O}}_{4}}^{3-}$ and harmful metals to surface waters.
    Description: Key Points: Organic topsoils leach substantial amounts of Fe when incubated in the absence of NO3, a competing electron acceptor that inhibits Fe reduction. Shallow catchments with fluvially coupled topsoils and low NO3 availability release 200 fold more Fe than steep ones with high NO3 abundance. Catchment topography and NO3 availability explain 62%–64% of the variability of Fe concentration and OC:Fe and P:Fe ratios across 88 streams.
    Description: EFRE‐Europe
    Description: https://doi.org/10.4211/hs.43601618877945c5a46b715aa98db729
    Keywords: ddc:551.9
    Language: English
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    As above, so below? Effects of fungicides on microbial organic matter decomposition are stronger in the hyporheic than in the benthic zone (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-04
    Description: Microbial organic matter decomposition is a critical ecosystem function, which can be negatively affected by chemicals. Although the majority of organic matter is stored in sediments, the impact of chemicals has exclusively been studied in benthic systems. To address this knowledge gap, we assessed the impact of a fungicide mixture at three concentrations on the decomposition of black alder leaves in the benthic and hyporheic zone. We targeted two sediment treatments characterized by fine and coarse grain sizes (1–2 vs. 2–4 mm). Besides microbial communities' functioning (i.e., decomposition), we determined their structure through microbial biomass estimates and community composition. In absence of fungicides, leaf decomposition, microbial biomass estimates and fungal sporulation were lower in the hyporheic zone, while the importance of bacteria was elevated. Leaf decomposition was reduced (40%) under fungicide exposure in fine sediment with an effect size more than twice as high as in the benthic zone (15%). These differences are likely triggered by the lower hydraulic conductivity in the hyporheic zone influencing microbial dispersal as well as oxygen and nutrient fluxes. Since insights from the benthic zone are not easily transferable, these results indicate that the hyporheic zone requires a higher recognition with regard to ecotoxicological effects on organic matter decomposition.
    Description: German Research Foundation, Project AQUA‐REG http://dx.doi.org/10.13039/501100001659
    Keywords: ddc:550.724 ; ddc:579
    Language: English
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    Feasibility of pXRF to evaluate chosen heavy metals in soil highly influenced by municipal waste disposal—A monitoring study of a former sewage farm (2022)
    John Wiley & Sons, Ltd. | Chichester, UK
    Details
    Publication Date: 2022-04-04
    Description: Sewage disposal onto agricultural land may result in the high accumulation of organic wastes, which questions the applicability of typical elemental analysis used for the soil components. To monitor the contamination status of agricultural soils at a former sedimentation basin, after the long‐term cessation of wastewater irrigation, 110 locations (15–20 cm depth) and 4 boreholes (up to 100 cm depth) were sampled to determine pH, loss on ignition, and concentration of Ni, Cu, Pb, Zn, and Cr. Additionally, the applicability of portable X‐ray fluorescence (pXRF) for the soil samples highly influenced by the organic wastes was evaluated. The study revealed the presence of a relatively homogenous sewage waste layer (depth of 20 cm), characterized by slightly acidic to neutral pH (6.3–7.5), high organic matter (OM) accumulation (up to 49%), and elevated concentration (mg kg −1) ranges between: Pb (5–321), Cu (31–2828), Ni (10–193), Cr (14–966), and Zn (76–6639). The pXRF analysis revealed metal concentration increase in mineral samples (up to 50%). The regression models and correction factors demonstrated high correlation and significance of pXRF measurement with response to increasing OM content, with the lowest r 2 = 0.86 obtained for Ni. Correlation of pXRF and AES measurement illustrated element‐dependent response for soils high in organics. Zn, Cu, and Cr pXRF analysis led to a slight underestimation in lower values, but overall good correlations (0.87; 0.89; and 0.88 respectively). Pb and Ni pXRF measurement revealed higher deviation from the reference in both lower and higher concentrations (0.74 and 0.70, respectively).
    Description: German Federation of Industrial Research Associations http://dx.doi.org/10.13039/501100002723
    Description: Federal Ministry for Economic Affairs and Energy http://dx.doi.org/10.13039/501100006360
    Keywords: ddc:577.14
    Language: English
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    Kinematics of Crystal Growth in Single‐Seal Syntaxial Veins in Limestone ‐ A Phase‐Field Study (2021)
    Details
    Publication Date: 2022-04-04
    Description: Building on recent developments in phase‐field modeling of structural diagenesis, we present an analysis of single‐seal syntaxial calcite vein microstructure in a variety of limestones. We focus on the effects of fracture aperture, intergranular versus transgranular fracturing, crystal habit and the presence of second phases in the host rock, to systematically investigate a simplified set of models covering the main classes of limestone in 2D. We incorporate the kinematic process of growth competition between differently oriented crystals, growth rate anisotropy between rough and faceted crystal surfaces and different growth rates on intergranular to transgranular fractures. Results show that within the considered parameter space we can reproduce a wide range of vein microstructures in limestone known in nature, such as stretched crystals, wide‐blocky veins, and elongated crystals. We identify five archetypes of vein microstructures in limestones, which are diagnostic for different kinematics and evolution of transport processes and illustrate the effect of key parameters in microstructure maps. We show how syntaxial veins with median line form after intergranular fracturing, while stretched crystals indicate transgranular fracturing. Intergranular fracturing leads to stronger growth competition and more prominent CPO in syntaxial veins. Our results can be extended to 3D to include multiple crack‐seal events, pore‐space cementation and simulation of fluid flow, providing a generic platform for modeling structural diagenesis in limestones.
    Description: Plain Language Summary: Fractures are ubiquitous in in the earth crust, forming important pathways for geothermal fluids. This fluid is often supersaturated, allowing crystals to grow in the open fractures which leads to fracture healing over time. During this self‐sealing of the fractured rock the permeability and strength of the rock change with many important consequences for subsurface engineering. In this study, we simulate the complex growth process and show how different crystal structures (e.g., stretched, blocky) form in open fractures in different types of limestone and compare our results to natural rock samples. We test different factors on how they affect the crystal morphology as fracture type (crack cuts though grain or along grain boundaries), opening width of the fracture, and coated grain surfaces (which can reduce the crystal growth rate). We are able to reproduce a wide range of crystal structures which occur in natural limestone, and present a framework for interpreting the evolution process of calcite veins in limestones. The systematic data analysis provides valuable insight in structure‐property linkages enabling a prediction of fracture healing mechanisms.
    Description: Key Points: Systematic phase‐field study captures formation of a wide range of single seal veins in limestones and provides insight to fracture healing. Effects of different parameters are illustrated in morphology maps and show diagnostic microstructures. Transgranular fracturing leads to stretched crystals and intergranular fracturing leads to more prominent CPO in syntaxial veins.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: https://doi.org/10.5281/zenodo.4597529
    Keywords: ddc:548
    Language: English
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    From consumer to enterprise grade: How the choice of four UAS impacts point cloud quality (2021)
    Details
    Publication Date: 2022-04-04
    Description: Uncrewed aerial systems (UAS), combined with structure‐from‐motion photogrammetry, has already proven to be very powerful for a wide range of geoscience applications and different types of UAS are used for scientific and commercial purposes. However, the impact of the UAS used on the accuracy of the point clouds derived is not fully understood, especially for the quantitative analysis of geomorphic changes in complex terrain. Therefore, in this study, we aim to quantify the magnitude of systematic and random error in digital elevation models derived from four commonly used UAS (XR6/Sony α6000, Inspire 2/X4s, Phantom 4 Pro+, Mavic Pro) following different flight patterns. The vertical error of each elevation model is evaluated through comparison with 156 GNSS reference points and the normal distribution and spatial correlation of errors are analysed. Differences in mean errors (−0.4 to −1.8 cm) for the XR6, Inspire 2 and Phantom 4 Pro are significant but not relevant for most geomorphological applications. The Mavic Pro shows lower accuracies with mean errors up to 4.3 cm, thus showing a higher influence of random errors. QQ plots revealed a deviation of errors from a normal distribution in almost all data. All UAS data except Mavic Pro exhibit a pure nugget semivariogram, suggesting spatially uncorrelated errors. Compared to the other UAS, the Mavic Pro data show trends (i.e. differences increase with distance across the survey—doming) and the range of semivariances is 10 times greater. The lower accuracy of Mavic Pro can be attributed to the lower GSD at the same flight altitude and most likely, the rolling shutter sensor has an effect on the accuracy of the camera calibration. Overall, our study shows that accuracies depend highly on the chosen data sampling strategy and that the survey design used here is not suitable for calibrating all types of UAS camera equally.
    Description: In this study, we aim to quantify the magnitude of systematic and random error in digital elevation models derived from four commonly used UAS (XR6/Sony α6000, Inspire 2/X4s, Phantom 4 Pro+, Mavic Pro) following different flight patterns. Differences in mean errors (−0.4 to −1.8 cm) for the XR6, Inspire 2 and Phantom 4 Pro are significant but not relevant for most geomorphological applications. Compared to the other UAS, the Mavic Pro data show trends (i.e., differences increase with distance across the survey—doming), and the range of semivariances is 10 times greater. The lower accuracy of Mavic Pro can be attributed to the lower GSD at the same flight altitude, and most likely, the rolling shutter sensor has an effect on the accuracy of the camera calibration.
    Keywords: ddc:526.982
    Language: English
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    Evaluating urban micrometeorites as a research resource—A large population collected from a single rooftop (2021)
    Details
    Publication Date: 2022-04-04
    Description: We report the recovery and characterization of a new urban micrometeorite collection derived from the rooftop of an industrial building in Germany. We identified 315 micrometeorites (diameter: 55–515 µm, size peak: ˜150 µm, size distribution slope exponent: −2.62). They are predominantly S‐type cosmic spherules (97.2%) but also two G‐type spherules (0.6%), an unmelted coarse‐grained single‐mineral micrometeorite, and eight scoriaceous particles (2.5%) or particles transitional between scoriaceous micrometeorites and porphyritic spherules. Their analysis details how the magnetite rim on partially melted micrometeorites is progressively diluted as the melt fraction increases during heating. At least 10 micrometeorites contain platinum group nuggets (PGNs). They have chondritic compositions but are depleted in volatile Pd. However, a single nugget preserves chondritic Pd concentrations. We suggest that an Fe‐Ni‐S bead originally containing the PGN escaped its host cavity and wet the particle exterior, creating an Fe‐rich melt that protected the nugget from evaporation. This melt layer oxidized forming magnetite—indicating that wetting events can affect the texture and composition of micrometeorites. Utilizing the well‐constrained surface area (8400 m2) and rooftop age (21 yr), we attempted the first global mass flux estimate based on urban micrometeorite data. This produced anomalously low values (13.4 t yr–1), even when correcting for losses due to sample processing (〈89.7 t yr–1). Our value is approximately two orders of magnitude lower than previous estimates, indicating that 〉99% of particles are missing, having been lost via drainage and cleaning. Rooftop collection sites have limited potential for mass flux calculations unless problems of loss can be resolved. However, urban micrometeorite collections have other advantages, notably exceptionally well‐preserved particles with extremely young terrestrial ages and the ability to extract many micrometeorites from accessible sites. Urban micrometeorites should be considered complementary to Antarctic and deep‐sea collections with potential for citizen science and educational exploitation.
    Keywords: ddc:549.112
    Language: English
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  • 30
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    Simulating Linear Kinematic Features in Viscous‐Plastic Sea Ice Models on Quadrilateral and Triangular Grids With Different Variable Staggering (2021)
    Details
    Publication Date: 2022-04-04
    Description: Observations in polar regions show that sea ice deformations are often narrow linear features. These long bands of deformations are referred to as Linear Kinematic Features (LKFs). Viscous‐plastic sea ice models have the capability to simulate LKFs and more generally sea ice deformations. Moreover, viscous‐plastic models simulate a larger number and more refined LKFs as the spatial resolution is increased. Besides grid spacing, other aspects of a numerical implementation, such as the placement of velocities and the associated degrees of freedom, may impact the formation of simulated LKFs. To explore these effects this study compares numerical solutions of sea ice models with different velocity staggering in a benchmark problem. Discretizations based on A‐,B‐, and C‐grid systems on quadrilateral meshes have similar resolution properties as an approximation with an A‐grid staggering on triangular grids (with the same total number of vertices). CD‐grid approximations with a given grid spacing have properties, specifically the number and length of simulated LKFs, that are qualitatively similar to approximations on conventional Arakawa A‐grid, B‐grid, and C‐grid approaches with half the grid spacing or less, making the CD‐discretization more efficient with respect to grid resolution. One reason for this behavior is the fact that the CD‐grid approach has a higher number of degrees of freedom to discretize the velocity field. The higher effective resolution of the CD‐discretization makes it an attractive alternative to conventional discretizations.
    Description: Plain Language Summary: Sea ice in the Arctic and Antarctic Oceans plays an important role in the exchange of heat and freshwater between the atmosphere and the ocean and hence in the climate in general. Satellite observations of polar regions show that the ice drift sometimes produces long features that are either cracks (leads) and zones of thicker sea ice (pressure ridges). This phenomenon is called deformation. It is mathematically described by the non‐uniform way in which the ice moves. For numerical models of sea ice motion it is difficult to represent this deformation accurately. Details of the numerics may affect the way these models simulate leads and ridges, their number and length. Specifically, we find by comparing different numerical models, that the way the model variables are ordered on a computational grid to solve the mathematical equations of sea ice motion has an effect of how many deformation features can be represented on a grid with a given spacing between grid points. A new discretization (ordering of model variables) turns out to resolve more details of the approximated field than traditional methods.
    Description: Key Points: The placement of the sea ice velocity has a mayor influence on the number of simulated linear kinematic features (LKFs). The CD‐grid resolves twice as many LKFs compared to A, B, C‐grids. A, B, C‐grids on quadrilateral meshes resolve a similar number of LKFs as A‐grids on triangular meshes (with the same total number of nodes).
    Keywords: ddc:550 ; ddc:551.343
    Language: English
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    Nutrient co‐limitation in the subtropical Northwest Pacific (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-04
    Description: Nutrients limiting phytoplankton growth in the ocean are a critical control on ocean productivity and can underpin predicted responses to climate change. The extensive western subtropical North Pacific is assumed to be under strong nitrogen limitation, but this is not well supported by experimental evidence. Here, we report the results of 14 factorial nitrogen–phosphorus–iron addition experiments through the Philippine Sea, which demonstrate a gradient from nitrogen limitation in the north to nitrogen–iron co‐limitation in the south. While nitrogen limited sites responded weakly to nutrient supply, co‐limited sites bloomed with up to ~60‐fold increases in chlorophyll a biomass that was dominated by initially undetectable diatoms. The transition in limiting nutrients and phytoplankton growth capacity was driven by a gradient in deep water nutrient supply, which was undetectable in surface concentration fields. We hypothesize that this large‐scale phytoplankton response gradient is both climate sensitive and potentially important for regulating the distribution of predatory fish.
    Description: National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809
    Keywords: ddc:577.7 ; ddc:550.724
    Language: English
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  • 32
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    The Eco‐Exposome Concept: Supporting an Integrated Assessment of Mixtures of Environmental Chemicals (2021)
    Details
    Publication Date: 2022-04-04
    Description: Organisms are exposed to ever‐changing complex mixtures of chemicals over the course of their lifetime. The need to more comprehensively describe this exposure and relate it to adverse health effects has led to formulation of the exposome concept in human toxicology. Whether this concept has utility in the context of environmental hazard and risk assessment has not been discussed in detail. In this Critical Perspective, we propose—by analogy to the human exposome—to define the eco‐exposome as the totality of the internal exposure (anthropogenic and natural chemicals, their biotransformation products or adducts, and endogenous signaling molecules that may be sensitive to an anthropogenic chemical exposure) over the lifetime of an ecologically relevant organism. We describe how targeted and nontargeted chemical analyses and bioassays can be employed to characterize this exposure and discuss how the adverse outcome pathway concept could be used to link this exposure to adverse effects. Available methods, their limitations, and/or requirement for improvements for practical application of the eco‐exposome concept are discussed. Even though analysis of the eco‐exposome can be resource‐intensive and challenging, new approaches and technologies make this assessment increasingly feasible. Furthermore, an improved understanding of mechanistic relationships between external chemical exposure(s), internal chemical exposure(s), and biological effects could result in the development of proxies, that is, relatively simple chemical and biological measurements that could be used to complement internal exposure assessment or infer the internal exposure when it is difficult to measure. Environ Toxicol Chem 2022;41:30–45. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
    Description: Illustration of the eco‐exposome assessment and how chemical analysis and bioassays could be used to estimate internal exposure. MIE = molecular initiation event; KE = key event; AO = adverse outcome.
    Description: DAAD German academic exchange service
    Keywords: ddc:577.14
    Language: English
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  • 33
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    Highlighting Theodor W. Engelmann's “Farbe und Assimilation” [Color and Assimilation] (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-04
    Description: In 1883, Theodor Wilhelm Engelmann, a German scientist, wrote his essay “color and assimilation” (Ger.: “Farbe und Assimilation”) describing the state of the art in photosynthesis research, his recent findings, and further assumptions based upon his presented results. Nearly 140 years later, many of his assumptions were proven correct. By his still well‐known bacteria experiments using aerotactic, heterotrophic bacteria, he identified the chloroplasts as the location in which photosynthesis and oxygen production takes place. Furthermore, by evaluating the effects of different light spectra, he constructed the first action spectra that demonstrated the implication of the “green gap” of chlorophylls. He further posited that accessory photosynthetic pigments existed to extend the absorption range of chlorophyll. Although infrequently cited, his work was foundational for current ecological research of the vertical appearance of algae species within the underwater gradient in light spectrum due to specific harvesting of different light spectra, hence complementary chromatic adaptation of communities. This short retrospective highlights this piece of literature that represents an early step toward our current understanding of ecological competition for light spectra.
    Keywords: ddc:572.46 ; ddc:570.9
    Language: English
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  • 34
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    Duvalo “Volcano” (North Macedonia): A Purely Tectonic‐Related CO2 Degassing System (2022)
    Wiley-AGU
    Details
    Publication Date: 2022-04-01
    Description: Duvalo “volcano” is a site of anomalous geogenic degassing close to Ohrid (North Macedonia) not related to volcanic activity, despite its name. CO2 flux measurements made with the accumulation chamber (321 sites over ∼50,000 m2) showed fluxes up to nearly 60,000 g m−2 d−1, sustaining a total output of ∼67 t d−1. Soil gas samples were taken at 50 cm depth from sites with high CO2 fluxes and analyzed for their chemical and isotope composition. The gas is mainly composed by CO2 (〉90%) with significant concentrations of H2S (up to 0.55%) and CH4 (up to 0.32%). The isotope compositions of He (R/RA 0.10) and of CO2 (δ13C ∼ 0‰) exclude significant mantle contribution, while δ13C-CH4 (∼−35‰) and δ2H-CH4 (∼−170‰) suggest a thermogenic origin for CH4. The area is characterized by intense seismic activity and Duvalo corresponds to an active tectonic structure bordering the Ohrid graben. The production of H2S within the stratigraphic sequence may be explained by thermochemical reduction of sulfate. The uprising H2S is partially oxidized to sulfuric acid that, reacting with carbonate rocks, releases CO2. The tectonic structure of the area favors fluid circulation, sustaining H2S production and oxidation, CO2 production and allowing the escape of the gases to the atmosphere. In the end, Duvalo represents a tectonic-related CO2 degassing area whose gases originate mostly, if not exclusively, in the shallowest part of the crust (〈10 km). This finding highlights that even systems with trivial mantle contribution may sustain intense CO2 degassing (〉1,000 t km−2 d−1).
    Description: Published
    Description: e2021GC010198
    Description: 6A. Geochimica per l'ambiente e geologia medica
    Description: JCR Journal
    Keywords: Geogenic degassing ; CO2 fluxes ; 04. Solid Earth
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: article
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    Emissioni naturali e antropiche di gas endogeno nella piana del Tevere da Roma alla foce. (2022)
    Università degli Studi Roma Tre - CROMA
    Details
    Publication Date: 2022-04-01
    Description: Il margine tirrenico dell’Italia centrale dalla Toscana alla Campania è caratterizzato dalla presenza di una fascia di apparati vulcanici, estinti o quiescenti, e mostra un assetto geodinamico con litosfera assottigliata, alti flussi di calore e forte degassamento di anidride carbonica (CO2) e altri gas di origine magmatica, mantellica o geotermica. I gas che risalgono si disciolgono in acquiferi profondi, se ospitati in rocce Mesozoiche carbonatiche, o superficiali, se ospitati in rocce clastiche o vulcaniche Neogeniche e Quaternarie. Tutti questi acquiferi rilasciano gas alla superficie attraverso sistemi aperti di faglie o fratture, generando zone di emissione anomala in atmosfera (fig. 1). In zone dove non vi è significativa emissione, il gas potrebbe però essere confinato nel sottosuolo da livelli impermeabili efficienti. Quando scavi o perforazioni attraversano questi livelli, il gas in pressione può fuoriuscire anche in maniera violenta (fig. 2). Numerosi incidenti di questo tipo sono avvenuti nei territori di Roma, di Fiumicino e ai Colli Albani. Sia le emissioni naturali che quelle di origine antropica possono rappresentare un pericolo per la salute umana o degli animali qualora i gas si accumulino in alte concentrazioni in depressioni del terreno, in scavi o in seminterrati.
    Description: Published
    Description: 45-51
    Description: 1TR. Georisorse
    Keywords: gas endogeni, piana del Tevere ; 04.04. Geology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
    Type: book chapter
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    Reconstruction of the subaerial Holocene volcanic activity through paleomagnetic and 14C dating methods: El Hierro (Canary Islands) (2022)
    Elsevier
    Details
    Publication Date: 2022-04-01
    Description: Volcanic hazard assessment relies on the accurate knowledge of the eruptive style and recurrence of volcanic eruptions in the past. At El Hierro (Canary Islands) historical and prehistorical records are still poorly defined, and although the island was the location of one of the most recent eruptions (La Restinga, 2011 CE) of the Canarian archipelago, the recent subaerial volcanism is still poorly studied. Information about the age of Holocene volcanic activity as well as the stratigraphy of the deposits is scarce: few eruptions are dated so far, whereas the others are classified as pre-or Holocene events considering lava flow characteristics along the coast. Here, we report on the dating of eleven (M˜na Chamuscada, M˜na del Tesoro, Orchilla, Las Calcosas, M˜na Negra, Lomo Negro, Below Lomo Negro, Cuchillo del Roque, Malpaso Member, and M˜na del Guanche) Holocene subaerial eruptions, distributed along the three rift zones, combining paleomagnetic and 14C methods. We also provide geochemical analyses for nine of them. Results indicate that M˜na Chamuscada and M˜na del Tesoro occurred more recently than previously considered, setting them within the last two thousand years. Conversely, paleomagnetic and 14C ages found for Lomo Negro eruption are consistent with literature data (Villasante- Marcos and Pav´on-Carrasco, 2014) and constrain the occurrence of this event in the XVI century CE. Finally, for Malpaso Member deposits, the two 14C datings obtained by charcoals found below and above the trachytic layer set the eruption during the Holocene epoch, between ~7300 BCE and ~4700 BCE. For the other eruptions, in two cases (Orchilla and Las Calcosas) many possible time windows during the last 14 ka have been found, whereas a few possible ages have been obtained for the others. On the whole, the resulting chronological reconstruction of the recent activity of El Hierro indicates that eruptions occurred unevenly along the three main rifts, with nine eruptions in the WNW rift, six in the NE rift, and four in the SSE rift. We document at least two periods characterized by high eruptive frequency: an old one, between 8000 BCE and 1000 BCE, with eight eruptions, three of which characterized by more evolved compositions (phonotephrite and trachyte), and a recent one, between 1000 BCE and present day, with at least seven eruptions, mainly showing basanite compositions. The new data yield a significant improvement of Holocene eruption chronology, thus are instrumental for a correct evaluation of the volcanic hazard at El Hierro.
    Description: Published
    Description: 107526
    Description: 1A. Geomagnetismo e Paleomagnetismo
    Description: JCR Journal
    Keywords: Paleomagnetism ; El Hierro ; 04.05. Geomagnetism ; 04.08. Volcanology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Scaling properties of seismicity and faulting (2022)
    Elsevier
    Details
    Publication Date: 2022-04-01
    Description: The Gutenberg–Richter law and the Omori law are both characterized by a scaling behavior. However, their relation is still an open question. Although several hypotheses have been formulated, a comprehen- sive geophysical mechanism is still missing to explain the observed variability of the scaling exponents b-value and p-value, e.g., correlating the seismic cycle to statistical seismology and tectonic processes. In this work, a model for describing the size-frequency scaling and the temporal evolution of seismicity is proposed starting from simple assumptions. The parameter describing how the number of earthquakes decreases after a major seismic event, p, turns out to be positively correlated to the exponent of the frequency-size distribution of seismicity, b, and related to tectonics. Our findings suggest that p ≈ 23 (b + 1). It implies that a relationship between fracturing regimes, “efficiency” of the seismic process, duration of the seismic sequences and geodynamic setting exists, with outstanding potential impact on seismic hazard. On the other hand, the Gutenberg–Richter law simply reflects the tendency of the segments of the Earth’s crust to reach mechanical stability via constrained energy-budget optimization. Each perturbation has a probability of growing an earthquake or not, depending on disorder within the fault zone and the energy accumulated in the adjoining volume, mainly controlling the evolution of seismic sequences. The results are consistent with the different energy sources related to the tectonic settings, i.e., gravitational in extensional regimes, having higher b and p values, and generating lower maximum magnitude earthquakes with respect to strike-slip and contractional settings, which are rather fueled by elastic energy, showing lower b and p values, and they may generate higher magnitude events.
    Description: Published
    Description: 117511
    Description: 3T. Fisica dei terremoti e Sorgente Sismica
    Description: JCR Journal
    Keywords: Gutenberg–Richter distribution ; fracturing and fault disorder ; Omori–Utsu law ; earthquake triggering ; tectonic setting ; 04.06. Seismology ; 04.07. Tectonophysics
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Arctic sea ice anomalies during the MOSAiC winter 2019/20 (2022)
    In:  EPIC3The Cryosphere, 16(3), pp. 981-1005, ISSN: 1994-0424
    Details
    Publication Date: 2022-04-01
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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    6th Data Science Symposium Abstracts (2021)
    In:  EPIC3
    Details
    Publication Date: 2022-04-01
    Description: The Data Science Symposium at Haus der Wissenschaft on 8/9 November 2021 in Bremen was the 6th Symposium in this series since 2017.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Miscellaneous , notRev
    Format: application/pdf
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  • 40
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    Use of the thermohaline method for determining the quasi-heterogeneity of the water masses in the Azov Sea (2022)
    Details
    Publication Date: 2022-04-02
    Description: This paper considers the possibility of applying the thermohaline method (using the construction of T,S-diagrams) to determine the quasi-heterogeneity of water layers in the Azov Sea drawing on the expedition data obtained in 2016–2020. The diagrams allowing to identify a two-layer water structure in the aquatic environment of the Azov Sea (excluding the area of Taganrog Bay) have been constructed. The analysis of water stratification in the conditions close to the natural regime of the sea (thus, including salinity), as well as in the present conditions of its salinization, has been carried out. The data obtained through the analysis of sample observations have been verified with mathematical methods; the explanations from the standpoint of T,S-analysis of the aquatic environment have been presented. The hydrological features of the salt regime of the Azov Sea are given with the specification of the situations during the advection of the Black Sea waters, which precondition a stable separation of the waters in the southern part of the sea into surface and bottom “water masses”. These possibilities are justified mathematically, and for the modern period of considerable salinization of the sea, in accordance with the theory of T,S-analysis of water masses, a classification assessment of the aquatic environment is proposed.
    Description: В работе рассмотрена возможность применения термохалинного способа (с построением T,S-диаграмм) определения квазиоднородности водных слоев в Азовском море на основании экспедиционных данных, полученных в период 2016–2020 гг. Построены диаграммы, позволяющие выявить в водной среде собственно Азовского моря (без учета Таганрогского залива) двухслойную структуру вод. Проведен анализ стратификации вод в условиях, близких к естественному режиму моря (а следовательно, и солености), а также в современных условиях его осолонения. Математическими приемами подтверждены данные анализа выборочных наблюдений и предложены объяснения с позиций T,S-анализа водной среды. Приводятся гидрологические особенности солевого режима Азовского моря с конкретизацией ситуаций в периоды адвекции черноморских вод, вследствие которой возникали условия для устойчивого разделения водной среды на юге моря на поверхностную и придонную «водные массы». Эти возможности обосновываются математически, а для современного периода значительного осолонения моря в соответствии с теорией T,S-анализа водных масс предлагается классификационная оценка водной среды.
    Description: Published
    Description: Refereed
    Keywords: Salinity effects ; Water stability ; Thermohaline method ; T,S-diagrams ; Water structure ; Водные массы ; Структура воды ; Устойчивость вод ; Термохалинный способ ; ASFA_2015::T::Thermohaline circulation ; ASFA_2015::W::Water temperature data ; ASFA_2015::W::Water masses
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.33-44
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  • 41
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    Age composition and linear growth of the invasive ark clam species (Anadara kagoshimensis (Tokunaga, 1906)) in the Kerch Strait (2022)
    Details
    Publication Date: 2022-04-02
    Description: Age composition and linear growth rate in the ark clam (Anadara kagoshimensis) population in the Kerch Strait are investigated. Based on the analysis of seasonal annual growth rings and chevron grooves on the hinge ligament of the ark clam, the age of this species has been examined, which, in this population, was found to be 7 years (6+). Based on the age and annual length gain of the molluscs in the course of their ontogenesis, a theoretical growth curve is presented; it has been calculated following the von Bertalanffy growth equation, where L∞, k, and t are the parameters equaling to 50.2, 0.428, and 0.022, respectively. The highest growth rate was observed in the first year of life, 17 mm; however, later on, it was consistently decreasing and did not exceed 2 mm/year in the oldest individuals. The relationship between the ark clam’s growth rate (PL) and its length, approximated by the inverse linear function is presented. Based on the parameters of the von Bertalanffy growth equation, a theoretical maximum age of the investigated species has been calculated; it was found to be 8.74 years. It has been shown that the linear growth rate of the ark clam in various areas of the Azov and Black Sea Basin is determined by the water salinity to a considerable extent, because in the desalinated areas (Azov Sea, Kerch Strait, Danube River Delta and Northwestern Black Sea with 10–14 ‰ salinity), the growth rate of this mollusc was 1.5–2 times lower than in the Southeastern Black Sea (18 ‰).
    Description: Исследована возрастная структура и скорость линейного роста популяции анадары (Anadara kagoshimensis) в Керченском проливе. На основе анализа сезонных годовых слоев роста и шевронных борозд на лигаментной площадке анадары изучен возраст этого вида, который в популяции составляет 7 лет (6+). На основе возраста и годового прироста моллюсков в течение онтогенеза представлена теоретическая кривая роста, рассчитанная по уравнению Берталанфи, где L∞, k, t — параметры, равные 50,2, 0,428 и 0,022, соответственно. Максимальная скорость роста наблюдалась в первый год жизни — 17 мм, однако в дальнейшем она устойчиво снижалась и у наиболее старых особей не превышала 2 мм/год. Показана связь скорости роста (PL) с длиной анадары, которая аппроксимируется обратной линейной функцией. На основе параметров уравнения Берталанфи рассчитан теоретически максимальный возраст исследуемого вида, который составил 8,74 года. Показано, что скорость линейного роста анадары в различных акваториях Азово-Черноморского бассейна в значительной степени определяется соленостью вод, поскольку в опресненных районах (Азовское море, Керченский пролив, дельта Дуная, северо-западная часть Черного моря с соленостью 10–14 ‰) темп роста моллюска был в 1,5–2 раза ниже, чем в юго-восточной части Черного моря (18 ‰).
    Description: Published
    Description: Refereed
    Keywords: Anadara kagoshimensis ; Growth rings ; Chevron grooves ; Salinity effects ; Von Bertalanffy equation ; Ark clam ; Годовые слои ; Анадара ; Шевронные борозды ; ASFA_2015::A::Age composition ; ASFA_2015::G::Growth rate ; ASFA_2015::M::Marine molluscs
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.45-55
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  • 42
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    Hydrochemical criteria for typification of the Azov limans of the Krasnodar Territory as the spawning grounds for semi-anadromous fish species (2022)
    Details
    Publication Date: 2022-04-02
    Description: The Azov limans of the Krasnodar Territory are of major fishery importance, as they serve as the spawning grounds for valuable semi-anadromous fish species. Roach and zander at their early stages of development are highly susceptible to the negative effects of various abiotic environmental factors, which makes them very dependent on the hydrochemical status of the water bodies during the spawning season. As the hydrochemical regime, in turn, closely depends on the hydrological regime and the overgrowth area of the limans, it can be used as a criterion parameter that affects the success of spawning of the semi-anadromous fish species and growth of their juveniles. This paper proposes a system of hydrochemical scoring and establishes the criteria for the typification of the limans based on their suitability for spawning and growing of zander and roach following the data collected in the spring season of 2017–2021. Based on the analysis of the hydrochemical data, 3 main blocks for the typification of limans according to their suitability for spawning of semi-anadromous fish species were identified: gas conditions, ionic composition and the content of biogenic components in water along with an assessment of the primary production of phytoplankton. It has been found out that the Azov limans of the Krasnodar Territory vary significantly in terms of the hydrochemical composition of their water. Some limans are characterized by pronounced fluctuations of the hydrochemical and ichthyological characteristics in interannual dynamics. Based on the hydrochemical criteria, the limans of the Kulikov-Ordynsk group (Bolshoy Bashtovy, Donchikov, Bolshoy Grushchany) and the Kulikovskiy Liman were the most favorable for the spawning of zander and roach, and the Ryasnoy, Boykievskiy and Kurchanskiy Limans were the least favorable. The low production coefficient in the water of most limans can be indicative of their high degree of overgrowth with macrophytes, which control is crucial in increasing the efficiency of natural reproduction of semi-anadromous fish species. The correlation between the criterion scoring of the limans based on the hydrochemical regime and the density of distribution of zander and roach juveniles has been established, which confirms the validity of this study.
    Description: Азовские лиманы Краснодарского края имеют важное рыбохозяйственное значение, поскольку они служат нерестилищами для ценных полупроходных видов рыб. Высокая чувствительность тарани и судака на ранних стадиях развития к негативному воздействию различных абиотических факторов окружающей среды делает их наиболее зависимыми от гидрохимического состояния водоемов в период размножения. Поскольку гидрохимический режим, в свою очередь, тесно зависит от гидрологического режима и уровня зарастаемости лиманов, его можно использовать в качестве критериального параметра, влияющего на успешность нереста полупроходных рыб и на рост их молоди. В работе предлагается балльная гидрохимическая оценка и выделяются критерии типизации лиманов по их пригодности для нереста и развития молоди судака и тарани на основе материалов, полученных в весенний период 2017–2021 гг. По результатам анализа гидрохимических данных было выделено 3 основных блока для типизации лиманов по их пригодности для воспроизводства полупроходных видов рыб: газовый режим, ионный состав и содержание в воде биогенных элементов с оценкой первичной продукции фитопланктона. Установлено, что азовские лиманы Краснодарского края значительно различаются между собой по гидрохимическому составу воды. Некоторые лиманы характеризуются выраженной вариабельностью гидрохимических и ихтиологических показателей в межгодовой динамике. По гидрохимическим критериям наиболее благоприятными для нереста судака и тарани являлись лиманы Куликово-Ордынской группы (Большой Баштовый, Дончиков, Большой Грущаный) и лиман Куликовский, неблагоприятными — лиманы Рясной, Бойкиевский и Курчанский. Низкий продукционный коэффициент в воде большинства лиманов может отражать высокую степень их зарастаемости макрофитами, борьба с которыми является основным приоритетным направлением для повышения эффективности естественного воспроизводства полупроходных видов рыб. Установлена корреляционная взаимосвязь критериальной оценки лиманов по гидрохимическому режиму и плотности распространения молоди судака и тарани, что подтверждает состоятельность данной работы.
    Description: Published
    Description: Refereed
    Keywords: Hydrochemical regime ; Roach ; Zander ; Juveniles ; Macrophytes ; Тарань ; Судак ; Полупроходные виды рыб ; Азовские лиманы ; Макрофиты ; ASFA_2015::A::Anadromous species ; ASFA_2015::A::Artificial rearing ; ASFA_2015::S::Spawning grounds
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.18-32
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  • 43
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    Effect of different doses of pituitary hormone on the reproductive performance of shemaya females (Alburnus leobergi, Freyhof & Kottelat, 2007) (2022)
    Details
    Publication Date: 2022-04-02
    Description: The stage of obtaining high-quality gonads was explored in the course of development of the biotechnology for artificial reproduction of the anadromous Azov-Black Sea shemaya Alburnus leobergi (Freyhof & Kottelat, 2007), a valuable species of the Azov Sea ichthyofauna. This research is aimed at the assessment of the maturity status of shemaya females and males after their wintering in the ponds of a fish farm on the Lower Don at a thermal constant of 849 degree days (DD) and at the evaluation of the reproductive parameters of shemaya females exposed to different doses of the pituitary extract. In all literary sources available, the information on this topic has been scarce and fragmentary, and in the foreign sources, it was entirely absent. Our investigation has shown that the gonads of 55 % of males were at 5th and 5th–6th stages of maturity. At the same time, females significantly differed by the degree of gonad maturity: 26.0 % of females had first-generation eggs at different stages of resorption, the sexual products of 15.8 % of females were at the 5th stage of maturity, and 58.2 % of females had immature sexual products at the 3rd–4th and 4th stages of maturity. The investigation of the effect of two doses (6.0 and 9.0 mg/kg) of the pituitary gland extract with application of the fractional method showed that 15.0 % and 16.7 % of injected shemaya females with the most mature eggs responded to the preliminary dose of the pituitary extract by ovulation of physiologically sound eggs (0.6 and 0.9 mg/kg, respectively). 20.0 % and 6.7 % of females responded to the provoking dose of pituitary hormone by ovulating physiologically high-quality eggs in accordance with the concentration applied. The fertilization rate of physiologically sound eggs in both scenarios had similar values (97.4 and 97.9 %). Since the thermal constant of 849 DD is excessive for the start of artificial reproduction of the Azov-Black Sea shemaya, it is necessary to conduct research in order to identify the thermal constant precluding the loss of the first-generation eggs caused by the incipient processes of resorption.
    Description: При разработке биотехники искусственного воспроизводства проходной черноморско-азовской шемаи Alburnus leobergi (Freyhof & Kottelat, 2007) — ценного вида азовской ихтиофауны — изучали этап получения качественных половых продуктов. Цель исследований — оценить состояние зрелости самок и самцов шемаи после зимнего выдерживания в зимовальных прудах рыбоводного хозяйства на Нижнем Дону при сумме тепла 849 градусо-дней (ГД) и репродуктивные показатели самок шемаи при воздействии разных доз гипофиза. Во всех доступных литературных источниках информация по данной теме была немногочисленной и фрагментарной; в зарубежных источниках ее не обнаружено вовсе. Исследования показали, что 55 % самцов имели половые продукты V и V– VI стадий зрелости. Самки в этот период значительно различались по степени зрелости половых продуктов: 26,0 % самок имели икру первой генерации в разных фазах резорбции, 15,8 % самок — половые продукты V стадии зрелости, 58,2 % самок — незрелые половые продукты III–IV и IV стадий зрелости. Исследование влияния двух доз гипофиза (6,0 и 9,0 мг/кг) дробным методом показало, что 15,0 и 16,7 % инъецированных самок шемаи с наиболее зрелой икрой ответили на предварительную дозу гипофиза овуляцией физиологически качественной икры (0,6 и 0,9 мг/кг, соответственно). На разрешающую дозу гормона гипофиза 20,0 и 6,7 % самок ответили овуляцией физиологически качественной икры соответственно примененным дозам. Степень оплодотворения физиологически качественной икры в обоих вариантах имела близкие значения (97,4 и 97,9 %). Поскольку сумма тепла 849 ГД является избыточной для начала воспроизводственных работ с черноморско-азовской шемаей, необходимо провести исследования для выявления уровня суммы тепла, который позволит избежать потерь икры первой генерации в результате начинающихся процессов резорбции.
    Description: Published
    Description: Refereed
    Keywords: Alburnus leobergi ; Hormonal stimulation ; Gonadosomatic index (GSI) ; Stages of maturity ; Artificial reproduction ; Pituitary gland extract ; Черноморско-азовская шемая ; Гормональная стимуляция ; Гонадосоматический индекс (ГСИ) ; Искусственное воспроизводство ; ООО «Рыбколхоз им. Мирошниченко» ; ASFA_2015::H::Hormones ; ASFA_2015::O::Oocytes ; ASFA_2015::S::Sexual maturity
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.56-67
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  • 44
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    Exotic fish species off the Black Sea coast of the Krasnodar Territory (2022)
    Details
    Publication Date: 2022-04-02
    Description: Each species strives to expand its range and spreads in all directions. Its expansion occurs in the direction where biological and abiotic factors are similar to its native habitat. Entering the area with different conditions activates the mechanism of adaptation to new conditions. If such an adaptation is successful, the range of this species expands in this direction, otherwise this area remains unclaimed. Possible migration routes of exotic species run along the coast of Turkey through the coast of the Republic of Georgia or along the coasts of Bulgaria, Romania and the Crimean Peninsula. Taking into account the existing system of currents in the sea, the most likely option seems to be their invasion into the Russian sector of the Black Sea as a result of migration from the Sea of Marmara through the Bosphorus Strait and further along the direction of the Anatolian and Caucasian currents. Another way is with ballast water. In 1995–2014, 7 monitoring stations under the authority of AzNIIRKH operated near the Black Sea coast of the Krasnodar Territory on a year-round basis. They were equipped with all the necessary types of fishing gear (set nets with a mesh size from 25 to 200 mm, bottom set nets with a minimum mesh size of 6.5 and 10 mm, cast nets with 30 mm mesh, etc.). AzNIIRKH-trained observers were present at each haul of the fishing gear and conducted the necessary catch analyses. All unusual species were preserved by freezing or taxidermy and transferred to the institute. As a result of the operation of AzNIIRKH monitoring stations, in the catches of commercial fishing gear off the Black Sea coast of the Krasnodar Territory in 2005 and 2012, two exotic species have been recorded: Siganus luridus (Rüppell, 1828) and Lophius piscatorius Linnaeus, 1758.
    Description: Каждый вид стремится расширить зону своего обитания и распространяется во все стороны. Расширение его происходит в том направлении, где биологические и абиотические факторы сходны с его нативным ареалом. При проникновении в акваторию с отличными условиями включается механизм адаптации к новым условиям. Если виду удается приспособиться к этим условиям, ареал расширяется и в этом направлении; в противном случае данная акватория видом не осваивается. Возможные пути миграции экзотических видов пролегают вдоль берегов Турции через побережье Республики Грузия или вдоль побережий Болгарии, Румынии и полуострова Крым. Учитывая существующую в море систему течений, наиболее вероятной представляется версия проникновения их в российский сектор Черного моря в результате миграции из Мраморного моря через пролив Босфор и далее — по направлению Анатолийского и Кавказского течений. Еще один путь — с балластными водами судов. В период 1995–2014 гг. круглогодично у черноморского побережья Краснодарского края работало 7 контрольно-наблюдательных пунктов (КНП) АзНИИРХ. Оснащены они были всеми необходимыми видами орудий лова (ставные сети с размером ячеи от 25 до 200 мм, донные ставные невода с минимальным размером ячеи 6,5 и 10 мм, закидные невода с ячеей 30 мм и др.). Прошедшие подготовку в АзНИИРХ наблюдатели присутствовали при каждой выборке орудий лова и проводили необходимые анализы уловов. Все необычные виды ими фиксировались путем заморозки или изготовления чучел и передавались в институт. В результате работ КНП АзНИИРХ в уловах промысловых орудий лова у черноморского побережья Краснодарского края в 2005 и 2012 гг. были отмечены два экзотических вида: Siganus luridus (Rüppell, 1828) и Lophius piscatorius Linnaeus, 1758.
    Description: Published
    Description: Refereed
    Keywords: Mediterraneanization ; Lophius piscatorius ; Siganus luridus ; Abiotic factors ; Fishing gear ; Экзотические виды ; Медитерранизация ; Орудия лова ; ASFA_2015::R::Rare species ; ASFA_2015::I::Introduced species ; ASFA_2015::G::Geographical distribution
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.89-95
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  • 45
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    Problems of using riverbed ponds in aquaculture (in the context of recent legislative changes) (2022)
    Details
    Publication Date: 2022-04-02
    Description: For a long time in the field of aquaculture existed the uncertainty, associated with the use of the ponds formed by water-retaining structures on watercourses (the so-called “riverbed ponds”), despite numerous attempts to resolve emerging contradictions legislatively—including another such attempt made last year by the adoption of Federal Law No. 163-FZ of June 11, 2021 “On the amendment of the Federal Law “On aquaculture (fish farming) and amendment of some legislative acts of the Russian Federation” and some legislative acts of Russian Federation”. The amendments introduced by this law establish new legal mechanisms for the use of riverbed ponds for the purposes of pond aquaculture, which makes their study particularly relevant. However, it will not be possible to fully understand the essence of these legislative changes without understanding the history and development of the legal framework applicable to these water bodies. In this regard, this article shows how riverbed ponds through numerous legislative changes were gradually introduced into the property circulation and how the principle of separation of the water resources of riverbed ponds and the land under them appeared, which means that the water in such ponds remains federal, but the land under them may be in other forms of ownership. This article also discusses the questions of the correlation of this principle with other principles of the legal regulation underlying water and land legislation, and how it is perceived by judicial practice. The author analyzed in detail the amendments, adopted by Federal Law of 11.06.2021 No. 163-FZ, concerning the regulation of riverbed ponds, proposed a classification of the legal basis for the use of water bodies in fish farming, and concluded what problems in the use of riverbed ponds remained, despite recent legislation attempts to eliminate them. Finally, this article suggests directions for further changes, according to which, as it seems to the author, the legislator could go to solve the identified problems.
    Description: На протяжении длительного времени в сфере аквакультуры сохраняется неопределенность в порядке использования прудов, образованных водоподпорными сооружениями на водотоках (т. н. «русловых прудов»), несмотря на многочисленные попытки законодательного урегулирования возникающих противоречий — включая очередную такую попытку, совершенную в прошлом году принятием Федерального закона от 11 июня 2021 г. No 163-ФЗ «О внесении изменений в Федеральный закон «Об аквакультуре (рыбоводстве) и о внесении изменений в отдельные законодательные акты Российской Федерации» и отдельные законодательные акты Российской Федерации». Поправки, внесенные указанным законом, устанавливают новые правовые механизмы использования русловых прудов для прудового рыбоводства, что делает их изучение особенно актуальным. Однако до конца понять суть произошедших изменений не удастся без осознания исторического развития правового режима данных водных объектов. В связи с этим в статье показано, как постепенно путем многочисленных законодательных изменений русловые пруды были введены в имущественный оборот, и появился принцип разделения водных ресурсов русловых прудов и земель под ними, из которого следует, что вода в таких прудах остается федеральной, а земельные участки под ними могут находиться в других формах собственности. Изучены вопросы о соотнесении обозначенного принципа с остальными принципами правового регулирования, лежащими в основе водного и земельного законодательств, и о его восприятии судебной практикой. Подробно проанализированы изменения, принятые Федеральным законом от 11.06.2021 No 163-ФЗ, в части, касающейся регулирования русловых прудов; с учетом указанных изменений предложена классификация оснований для использования водных объектов в рыбоводстве, а также сделан вывод о том, какие проблемы в использовании русловых прудов сохранились, несмотря на последние попытки законодателя их устранить. Наконец, предложены направления дальнейших изменений, по которым, как представляется автору, мог бы пойти законодатель для решения выявленных проблем.
    Description: Published
    Description: Refereed
    Keywords: Riverbed ponds ; Legislative acts ; Pond aquaculture ; Water use agreements ; Fish-breeding sites ; Русловые пруды ; Прудовая аквакультура ; Договоры водопользования ; Земли водного фонда ; Земли сельскохозяйственного назначения ; ASFA_2015::A::Aquaculture law ; ASFA_2015::F::Fish farms ; ASFA_2015::A::Agreements
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.96-120
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  • 46
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    Heavy metals and arsenic in water, bottom sediments and Black Sea turbot (Scophthalmus maeoticus, Pall., 1814) in the Caucasian Shelf area in the Black Sea (1995–2020) (2022)
    Details
    Publication Date: 2022-04-02
    Description: The results of investigation of the pollution of the water and bottom sediments of the Caucasian Shelf in the Black Sea by heavy metals (copper, zinc, lead, cadmium, mercury) and arsenic, as well as their content in the Black Sea turbot Scophthalmus maeoticus (Pallas, 1814) are presented for 1995–2020. In the water and turbot, the determination of Zn, Cu, Pb, As, and Cd has been conducted using the method of atomic absorption with electrothermal atomization; mercury in all components of the ecosystems was measured using the method of atomic absorption with “cold steam”; in the bottom sediments, the content of Zn, Cu, Pb and As was identified using X-ray fluorescence method. In 1995–2020, in some water samples, the concentrations of zinc, copper and mercury exceeded the maximum permissible level established for the water bodies of fisheries importance, while the lead and cadmium were below it. The arsenic content during the entire observation period was extremely low. A noticeable decrease in the concentrations of zinc, lead and copper in the shelf waters of the Black Sea in the present period as compared with the years of the greatest pollution (1995–2002) was recorded. In the bottom sediments, the content of lead, zinc and mercury exceeded their content in the earth's crust for several years; for arsenic, the excess was recorded throughout the entire observation period. This mostly results from the peculiarities of the granulometric composition of the shelf bottom and, to a much lesser extent, from anthropogenic influence. The differences in the bioaccumulation of heavy metals and arsenic in the organs of the Black Sea turbot are shown. Out of the identified elements, only lead, mercury and arsenic in isolated cases exceeded the permissible level in the organs of the turbot in some years.
    Description: Представлены результаты исследований загрязнения тяжелыми металлами (медь, цинк, свинец, кадмий, ртуть) и мышьяком воды и донных отложений Кавказского шельфа Черного моря и собственно черноморского калкана Scophthalmus maeoticus (Pallas, 1814) в период с 1995 по 2020 г. В воде и калкане определение Zn, Cu, Pb, As и Cd проводили методом атомной абсорбции с электротермической атомизацией; ртути во всех элементах экосистемы — методом атомной абсорбции в «холодном паре»; Zn, Cu, Pb и As в донных отложениях — рентгенфлуоресцентным методом. В отдельных пробах воды концентрации цинка, меди и ртути превышали предельно допустимую концентрацию для рыбохозяйственных водоемов, в то время как концентрации свинца и кадмия — нет. Содержание мышьяка в течение всего периода наблюдений оставалось крайне низким. Было отмечено заметное снижение концентраций цинка, свинца и меди в воде шельфа Черного моря в современный период по сравнению с периодом наибольшего загрязнения (1995–2002 гг.). В донных осадках содержание свинца, цинка и ртути в течение ряда лет превышало содержание в земной коре; для мышьяка превышение наблюдалось в течение всего периода наблюдений. Очевидно, что данная ситуация в большей степени связана с особенностями гранулометрического состава дна шельфа, чем с антропогенным влиянием. Показаны различия в биоаккумуляции тяжелых металлов и мышьяка органами черноморского калкана. Из перечня определяемых элементов превышение допустимого уровня в органах калкана отмечалось в отдельные годы в единичных случаях для свинца, ртути и мышьяка.
    Description: Published
    Description: Refereed
    Keywords: Scophthalmus maeoticus ; Mercury ; Copper ; Zinc ; Arsenic ; Cadmium ; Maximum permissible level ; Bottom sediments ; Калкан ; Тяжелые металлы ; Накопление ; Донные отложения ; ASFA_2015::H::Heavy metals ; ASFA_2015::M::Marine pollution ; ASFA_2015::S::Sediment pollution
    Repository Name: AquaDocs
    Type: Journal Contribution
    Format: pp.68-88
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  • 47
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    Aquatic Bioresources and Environment, vol. 5, issue 1 (2022)
    Azov-Black Sea Branch of FSBSI VNIRO (AzNIIRKH) | Rostov-on-Don, Russia
    Details
    Publication Date: 2022-04-02
    Description: Vertical distribution of biogenic elements in Gelendzhik area in 2019 has been presented. Hydrochemical criteria for typification of the Azov limans of the Krasnodar Territory as the spawning grounds for semi-anadromous fish species have been enlisted. Use of the thermohaline method for determining the quasi-heterogeneity of the water masses in the Azov Sea is discussed. Age composition and linear growth of the invasive ark clam species (Anadara kagoshimensis (Tokunaga, 1906)) in the Kerch Strait have been estimated. Effect of different doses of pituitary hormone on the reproductive performance of shemaya females (Alburnus leobergi, Freyhof & Kottelat, 2007) has been studied. Heavy metals and arsenic in water, bottom sediments and Black Sea turbot (Scophthalmus maeoticus, Pall., 1814) in the Caucasian Shelf area in the Black Sea (1995–2020) have been traced. Exotic fish species off the Black Sea coast of the Krasnodar Territory are presented. Problems of using riverbed ponds in aquaculture (in the context of recent legislative changes) are considered.
    Description: Published
    Description: Refereed
    Keywords: Marine molluscs ; Alburnus leobergi ; Scophthalmus maeoticus ; Anadara kagoshimensis ; Salinity effects ; Macrophytes ; Загрязнение воды ; Цинк ; Ртуть ; Экзотические виды ; Черноморско-азовская шемая ; Калкан ; Анадара ; ASFA_2015::A::Aquaculture law ; ASFA_2015::F::Fish farms ; ASFA_2015::M::Marine pollution
    Repository Name: AquaDocs
    Type: Book/Monograph/Conference Proceedings
    Format: 120pp.
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    NEGIS - A unique feature in Greenland? (2022)
    In:  EPIC3EastGRIP International Spring Seminar Series (EISSS) 2022, Online, 2022-03-2022-04
    Details
    Publication Date: 2022-04-04
    Description: Reliable knowledge of ice discharge dynamics for the Greenland Ice Sheet via its ice streams is essential if we are to understand its stability under future climate scenarios. Little however is known about the paleo ice-sheet configuration in areas still covered by ice. Here we use radio-echo sounding data to decipher the regional deformation history of the north-eastern Greenland Ice Sheet from its internal stratigraphy. We map folds deep below the surface that we attribute to the activity of a now-extinct ice stream, which shows strong similarities to the Northeast Greenland Ice Stream. We propose that locally this ancient ice flow regime reached much further inland than today’s and was ceased in the Holocene. The new insight that major ice streams may abruptly disappear will affect future approaches to understanding and modelling the response of Earth’s ice sheets to global warming.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
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    Greenland mass trends from airborne and satellite altimetry during 2011–2020 (2022)
    In:  EPIC3Journal of Geophysical Research: Earth Surface,, 127, pp. e2021JF006505
    Details
    Publication Date: 2022-04-04
    Description: We use satellite and airborne altimetry to estimate annual mass changes of the Greenland Ice Sheet. We estimate ice loss corresponding to a sea-level rise of 6.9 ± 0.4 mm from April 2011 to April 2020, with a highest annual ice loss rate of 1.4 mm/yr sea-level equivalent from April 2019 to April 2020. On a regional scale, our annual mass loss timeseries reveals 10–15 m/yr dynamic thickening at the terminus of Jakobshavn Isbræ from April 2016 to April 2018, followed by a return to dynamic thinning. We observe contrasting patterns of mass loss acceleration in different basins across the ice sheet and suggest that these spatiotemporal trends could be useful for calibrating and validating prognostic ice sheet models. In addition to resolving the spatial and temporal fingerprint of Greenland's recent ice loss, these mass loss grids are key for partitioning contemporary elastic vertical land motion from longer-term glacial isostatic adjustment (GIA) trends at GPS stations around the ice sheet. Our ice-loss product results in a significantly different GIA interpretation from a previous ice-loss product.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Article , isiRev
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    Exploring Geographic Variation in Fin Whale (Balaenoptera physalus) Calls From Two Passive Acoustic Monitoring Sites Revealing Population Identities Across the Weddell Sea, Antarctica (2021)
    In:  EPIC394 p.
    Details
    Publication Date: 2022-04-04
    Description: Currently, little is known about the population identity of fin whales (Balaenoptera physalus) in Antarctic waters but initial analyses of acoustic recordings from the Southern Ocean (SO) have shown that fin whale calls differ between regions, possibly representing different fin whale populations. In the Atlantic Sector of the Southern Ocean, the typical fin whale 20-Hz song is often accompanied by simultaneous higher frequency (HF) component at around 89Hz or 99Hz. However, the distribution of these call types throughout the area and whether there is a clear spatial separation between these call types is so far unknown. In this study fin whale calls were examined between two locations, the Greenwich Meridian and Elephant Island across the Weddell Sea (from 2009, 2011, 2013, and 2015) to gain further insights into the connections between fin whales in this region. The HF call component was found to be significantly (p-value 〈 2.2e^-16) unique in its frequency at the two locations with 99Hz (97.14Hz ± 3.19) at Greenwich Meridian and 86Hz (86.26Hz ± 1.36) at Elephant Island. The inter-pulse interval (IPI) of both low frequency (LF) (20-Hz) and HF calls were also found to differ between geographic regions, with a median IPI of 14.5 seconds at Elephant Island and median IPI around 10 seconds at Greenwich Meridian. Variation in song IPIs were also investigated between geographic locations, Elephant Island was determined to have a majority singlet song type and Greenwich Meridian was found to have mostly triplet songs. The occurrence of HF and LF calls showed a strong positive correlation, indicating that both call components are produced simultaneously. The characteristic elements for fin whale calls examined in this study all indicate that the fin whale calls recorded at Elephant Island and Greenwich Meridian belong to two distinct acoustic populations. An understanding of how potentially distinct fin whale stocks utilize different geographic regions is fundamental for management and conservation measures aiming to improve the conservation status of this vulnerable species.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Thesis , notRev
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    Carbon Dioxide and Methane Release Following Abrupt Thaw of Pleistocene Permafrost Deposits in Arctic Siberia (2021)
    Details
    Publication Date: 2022-04-07
    Description: The decomposition of thawing permafrost organic matter (OM) to the greenhouse gases (GHG) carbon dioxide (CO2) and methane forms a positive feedback to global climate change. Data on in situ GHG fluxes from thawing permafrost OM are scarce and OM degradability is largely unknown, causing high uncertainties in the permafrost‐carbon climate feedback. We combined in situ CO2 and methane flux measurements at an abrupt permafrost thaw feature with laboratory incubations and dynamic modeling to quantify annual CO2 release from thawing permafrost OM, estimate its in situ degradability and evaluate the explanatory power of incubation experiments. In July 2016 and 2019, CO2 fluxes ranged between 0.24 and 2.6 g CO2‐C m−2 d−1. Methane fluxes were low, which coincided with the absence of active methanogens in the Pleistocene permafrost. CO2 fluxes were lower three years after initial thaw after normalizing these fluxes to thawed carbon, indicating the depletion of labile carbon. Higher CO2 fluxes from thawing Pleistocene permafrost than from Holocene permafrost indicate OM preservation for millennia and give evidence that microbial activity in the permafrost was not substantial. Short‐term incubations overestimated in situ CO2 fluxes but underestimated methane fluxes. Two independent models simulated median annual CO2 fluxes of 160 and 184 g CO2‐C m−2 from the thaw slump, which include 25%–31% CO2 emissions during winter. Annual CO2 fluxes represent 0.8% of the carbon pool thawed in the surface soil. Our results demonstrate the potential of abrupt thaw processes to transform the tundra from carbon neutral into a substantial GHG source.
    Description: Plain Language Summary: Thawing of permanently frozen soils (permafrost) in the northern hemisphere forms a threat to global climate since these soils contain large amounts of frozen organic carbon, which might be decomposed to the greenhouse gases (GHGs) carbon dioxide (CO2) and methane upon thaw. How fast these GHGs are produced is largely unknown, since field observations of greenhouse gas fluxes from thawing permafrost are too sparse. Consequently, simulations on the effect of thawing permafrost soils on future climate are highly uncertain. We measured CO2 and methane fluxes from soils affected by abrupt permafrost thaw in Siberia during two summer seasons. We used these field observations and long‐term incubation data to calibrate two models that simulate the CO2 release over a whole year. We found that greenhouse gas fluxes were dominated by CO2 and that the minor importance of methane was due to the absence of methane producing microorganisms in the Pleistocene permafrost. The CO2 release in the first year accounted for 0.8% of thawed permafrost carbon but decomposition rates decreased after the depletion of the rapidly decomposable organic matter. Abrupt permafrost thaw turned the tundra into a substantial source of CO2, of which 25%–31% was released in the non‐growing season.
    Description: Key Points: Abrupt permafrost thaw turned the tundra into a substantial annual source of CO2 of which 25%–31% were released in the non‐growing season. About 0.8% of thawed permafrost carbon was decomposed to CO2 in one year but decomposition rates declined after the loss of labile carbon. Methane contributed a minor fraction to total greenhouse gas fluxes also because of a low methanogen abundance in Pleistocene permafrost.
    Description: German Ministry for Education and Research
    Description: German Research Foundation
    Description: https://doi.org/10.5281/zenodo.5584710
    Keywords: ddc:551
    Language: English
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    On incoherent diffractive imaging (2021)
    International Union of Crystallography | 5 Abbey Square, Chester, Cheshire CH1 2HU, England
    Details
    Publication Date: 2022-04-07
    Description: Incoherent diffractive imaging (IDI) promises structural analysis with atomic resolution based on intensity interferometry of pulsed X‐ray fluorescence emission. However, its experimental realization is still pending and a comprehensive theory of contrast formation has not been established to date. Explicit expressions are derived for the equal‐pulse two‐point intensity correlations, as the principal measured quantity of IDI, with full control of the prefactors, based on a simple model of stochastic fluorescence emission. The model considers the photon detection statistics, the finite temporal coherence of the individual emissions, as well as the geometry of the scattering volume. The implications are interpreted in view of the most relevant quantities, including the fluorescence lifetime, the excitation pulse, as well as the extent of the scattering volume and pixel size. Importantly, the spatiotemporal overlap between any two emissions in the sample can be identified as a crucial factor limiting the contrast and its dependency on the sample size can be derived. The paper gives rigorous estimates for the optimum sample size, the maximum photon yield and the expected signal‐to‐noise ratio under optimal conditions. Based on these estimates, the feasibility of IDI experiments for plausible experimental parameters is discussed. It is shown in particular that the mean number of photons per detector pixel which can be achieved with X‐ray fluorescence is severely limited and as a consequence imposes restrictive constraints on possible applications.
    Description: Starting from a simple model of stochastic fluorescence emission, a theory is derived of contrast formation and signal‐to‐noise ratio for incoherent diffractive imaging; its feasibility for plausible experimental parameters is discussed. image
    Keywords: ddc:548
    Language: English
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    Leaf Wax Hydrogen Isotopes as a Hydroclimate Proxy in the Tropical Pacific (2021)
    Details
    Publication Date: 2022-04-07
    Description: Hydrogen isotope ratios of sedimentary leaf waxes (δ2HWax values) are increasingly used to reconstruct past hydroclimate. Here, we add δ2HWax values from 19 lakes and four swamps on 15 tropical Pacific islands to an updated global compilation of published data from surface sediments and soils. Globally, there is a strong positive linear correlation between δ2H values of mean annual precipitation (δ2HP values) and the leaf waxes n‐C29‐alkane (R2 = 0.74, n = 665) and n‐C28‐acid (R2 = 0.74, n = 242). Tropical Pacific δ2HWax values fall within the predicted range of values based on the global calibration, and the largest residuals from the global regression line are no greater than those observed elsewhere, despite large uncertainties in δ2HP values at some Pacific sites. However, tropical Pacific δ2HWax values in isolation are not correlated with estimated δ2HP values from isoscapes or from isotope‐enabled general circulation models. Palynological analyses from these same Pacific sediment samples suggest no systematic relationship between any particular type of pollen distribution and deviations from the global calibration line. Rather, the poor correlations observed in the tropical Pacific are likely a function of the small range of δ2HP values relative to the typical residuals around the global calibration line. Our results suggest that δ2HWax values are currently most suitable for use in detecting large changes in precipitation in the tropical Pacific and elsewhere, but that ample room for improving this threshold exits in both improved understanding of δ2H variability in plants, as well as in precipitation.
    Description: Plain Language Summary: Past precipitation patterns are difficult to reconstruct, limiting our ability to understand Earth’s climate system. Geochemists reconstruct past precipitation by measuring the amount of heavy hydrogen naturally incorporated into the waxy coating of leaves, which is preserved in mud that accumulates in lakes, soils, and oceans. Heavy hydrogen in leaf waxes is strongly correlated with local precipitation, allowing us to learn about rainfall intensity, temperature, and cloud movement. However, no existing calibration studies include sites from the tropical Pacific, home to the most intense rainfall on the planet and populations that rely on rain for drinking water and farming. We measured heavy hydrogen in leaf waxes from tropical Pacific islands and show that although values are within the global calibration error, no precipitation relationship exists within the region. Plant type distributions do not explain the lack of correlation, which is best attributed to poorly constrained estimates of heavy hydrogen in local rain and the relatively small range of variability within the region. At present, heavy hydrogen from ancient leaf waxes can show large changes in past precipitation, but improved process‐level understanding is needed to use this tool to understand smaller changes in the tropical Pacific and elsewhere.
    Description: Key Points: Leaf wax 2H/1H ratios are correlated with mean annual precipitation 2H/1H ratios globally, but not in the tropical Pacific. Deviations from the global relationship between precipitation leaf wax 2H/1H ratios cannot be predicted from palynological assemblages. Small range and large uncertainties in estimates of tropical Pacific precipitation 2H/1H ratios likely account for poor correlations.
    Description: Swiss National Science Foundation
    Description: National Science Foundation (NSF) http://dx.doi.org/10.13039/100000001
    Description: Natural Environment Research Council (NERC) http://dx.doi.org/10.13039/501100000270
    Description: Department of Education and Training, Australian Research Council (ARC) http://dx.doi.org/10.13039/501100000923
    Description: http://10.0.15.89/ethz-b-000412154
    Keywords: ddc:551 ; ddc:577.7
    Language: English
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    The Goldilocks Zone in Cooling Demand: What Can We Do Better? (2022)
    Details
    Publication Date: 2022-04-07
    Description: The higher frequency and intensity of sustained heat events have increased the demand for cooling energy across the globe. Current estimates of summer‐time energy demand are primarily based on Cooling Degree Days (CDD), representing the number of degrees a day's average temperature exceeds a predetermined comfort zone temperature. Through a comprehensive analysis of the historical energy demand data across the USA, we show that the commonly used CDD estimates fall significantly short (±25%) of capturing regional thermal comfort levels. Moreover, given the increasingly compelling evidence that air temperature alone is not sufficient for characterizing human thermal comfort, we extend the widely used CDD calculation to heat index, which accounts for both air temperature and humidity. Our results indicate significant mis‐estimation of regional thermal comfort when humidity is ignored. Our findings have significant implications for the security, sustainability, and resilience of the grid under climate change.
    Description: Plain Language Summary: Hotter summer days and more frequent and intense heatwaves are causing a sharp rise in demand for air conditioning across the globe. Accurate estimation of demand for space cooling is an integral component of resilient planning, operation, and management of the grid. One widely used metric for characterizing this demand is the Cooling Degree Days (CDD), which is calculated by measuring the difference between the mean daily temperature and a pre‐defined base temperature that represents a “comfort zone.” In this study, we analyze historical data on climate and energy demand and find that the most frequently used base temperature of 65°F in CDD calculations leads to mis‐characterizing comfort zones across different geographic areas in the United States. This can cause significant under‐ or over‐estimations of cooling energy demand. Moreover, we extend the temperature‐based CDD calculations to also account for the role of humidity and demonstrate the cost of ignoring humidity in CDD calculations under present and future climate conditions.
    Description: Key Points: Analysis of electricity demand shows that the widely used Cooling Degree Days (CDD) estimates fall short of capturing regional thermal comfort zones. Estimates of air conditioning penetration and affordability based on traditional calculation of CDD can lead to significant misestimation. Extending CDD calculations to include humidity improves the characterization of climate‐demand nexus under present and future climate.
    Description: National Science Foundation (NSF) http://dx.doi.org/10.13039/100000001
    Keywords: ddc:333.79
    Language: English
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    Habitat availability determines food chain length and interaction strength in food webs of a large lowland river (2021)
    John Wiley & Sons, Ltd. | Chichester, UK
    Details
    Publication Date: 2022-04-07
    Description: Many large rivers used for navigation have lost their hydromorphological heterogeneity, which has led to the widespread loss of native biodiversity and the concurrent establishment of non‐native communities. While the effects on biodiversity are well‐described, we know little about how the loss of natural habitats and the restructuring of communities cumulate into effects on riverine food webs. We constructed binary and ingestion webs for benthic macroinvertebrates and their resources in the Elbe River (Germany) and compared if food chain length, food web complexity, robustness, ingestion rates, and consumer‐resource interaction strength differ among three shoreline engineering practices. Food webs at profoundly altered shorelines were significantly less complex and had significantly shorter food chains than the food web at the semi‐natural shoreline. However, food web robustness to a simulated loss of species was comparable at all shorelines. Total ingestion rates were up to eight times lower at highly altered shorelines due to significantly lower ingestion rates by native species. Predator–prey interaction strength was comparable among shorelines due to higher shares of non‐native predators, indicating that non‐native predators can be functionally equivalent to native predators. We attributed the observed food web differences to the absence of complex habitats at profoundly altered shorelines and the accompanied absence of specialized consumers. Our study provides empirical evidence that hydromorphological modifications reduce the efficiency of food webs to control organic matter dynamics and may ultimately affect the provisioning of riverine ecosystem services.
    Keywords: ddc:339.95 ; ddc:551.483
    Language: English
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    Comprehensive analysis of chemical and biological problems associated with browning agents used in aquatic studies (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-07
    Description: Inland waters receive and process large amounts of colored organic matter from the terrestrial surroundings. These inputs dramatically affect the chemical, physical, and biological properties of water bodies, as well as their roles as global carbon sinks and sources. However, manipulative studies, especially at ecosystem scale, require large amounts of dissolved organic matter with optical and chemical properties resembling indigenous organic matter. Here, we compared the impacts of two leonardite products (HuminFeed and SuperHume) and a freshly derived reverse osmosis concentrate of organic matter in a set of comprehensive mesocosm‐ and laboratory‐scale experiments and analyses. The chemical properties of the reverse osmosis concentrate and the leonardite products were very different, with leonardite products being low and the reverse osmosis concentrate being high in carboxylic functional groups. Light had a strong impact on the properties of leonardite products, including loss of color and increased particle formation. HuminFeed presented a substantial impact on microbial communities under light conditions, where bacterial production was stimulated and community composition modified, while in dark potential inhibition of bacterial processes was detected. While none of the browning agents inhibited the growth of the tested phytoplankton Gonyostomum semen, HuminFeed had detrimental effects on zooplankton abundance and Daphnia reproduction. We conclude that the effects of browning agents extracted from leonardite, particularly HuminFeed, are in sharp contrast to those originating from terrestrially derived dissolved organic matter. Hence, they should be used with great caution in experimental studies on the consequences of terrestrial carbon for aquatic systems.
    Description: Marie Curie International Outgoing Fellowship
    Description: Swedish Research Council Formas http://dx.doi.org/10.13039/501100001862
    Description: Knut and Alice Wallenberg Foundation http://dx.doi.org/10.13039/501100004063
    Keywords: ddc:551.48 ; ddc:550.724
    Language: English
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    Vertically Divergent Responses of SOC Decomposition to Soil Moisture in a Changing Climate (2022)
    Details
    Publication Date: 2022-04-07
    Description: The role of soil moisture for organic matter decomposition rates remains poorly understood and underrepresented in Earth System Models (ESMs). We apply the Dual Arrhenius Michaelis‐Menten (DAMM) model to a selection of ESM soil temperature and moisture outputs to investigate their effects on decomposition rates, at different soil depths, for a historical period and a future climate period. Our key finding is that the inclusion of soil moisture controls has diverging effects on both the speed and direction of projected decomposition rates (up to ±20%), compared to a temperature‐only approach. In the top soil, the majority of these changes is driven by substrate availability. In deeper soil layers, oxygen availability plays a relatively stronger role. Owing to these different moisture controls along the soil depth, our study highlights the need for depth‐resolved inclusion of soil moisture effects on decomposition rates within ESMs. This is particularly important for C‐rich soils in regions which may be subject to strong future warming and vertically opposing moisture changes, such as the peat soils at northern high latitudes.
    Description: Plain Language Summary: Soils contain a lot of carbon (C). Earth System Models (ESMs) predict that the amount of C released from soils into the atmosphere as CO2 will increase in response to increased warming and microbial activity. Soil moisture also controls microbial C decomposition, but most ESMs do not yet describe this process very well. In this study we apply a simple equation to different ESMs, to see how both temperature and soil moisture change microbial decomposition under future climate. First, we show that the speed of C released into the atmosphere changes when we include soil moisture changes, compared to what is expected due to warming alone. Second, we found that the future speed at which carbon that can be decomposed in the topsoil mainly depends on how much carbon microbes have access to, but that in the deeper soil this process becomes much more affected by the absence/presence of oxygen. Including these soil moisture interactions in ESMs for different soil depths is important to predict whether soils will store more or less C in the future. Our findings are particularly relevant for high latitude soils which store large amounts of C, will warm fast, and experience frequent (re)wetting and drying.
    Description: Key Points: Considering soil moisture effects can change modeled decomposition rates by up to ±20% compared to considering only temperature effects. The majority of these changes are driven by substrate availability, in particular in the top soil. In the subsoil, oxygen availability becomes an increasingly important factor.
    Description: Norwegian Research Council
    Description: https://doi.org/10.5281/zenodo.5654554
    Keywords: ddc:631.4
    Language: English
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    Telerilevamento di vibrazioni delle strutture tramite telesensore infrasonico (2022)
    INGV
    Details
    Publication Date: 2022-04-06
    Description: Nell’ambito del progetto EDISECUR, finanziato della regione Lazio, è stato sviluppato un prototipo di telesensore infrasonico, TIS, a tracciamento di speckle per la misura della velocità angolare, delle frequenze fondamentali e delle armoniche di una superficie sottoposta a oscillazioni. Il TIS si presta particolarmente per il rilevamento e il monitoraggio nel tempo degli edifici, ponti e altri manufatti. Conoscere lo stato vibrazionale di queste strutture può essere d’interesse sia per la loro caratterizzazione dinamica che per la sicurezza. Questo prototipo, sufficientemente compatto, si presta a una misura immediata della velocità angolare e, con semplici operazioni, si possono dedurre spostamenti e accelerazioni angolari. Dalle grandezze angolari e dalla conoscenza geometrica della superficie, tramite alcuni schemi ed esempi, si mostra come sia possibile determinare anche altri parametri cinematici lineari. Il telesensore può essere impiegato nelle misure delle vibrazioni di superfici a lunga distanza di varia natura, anche laddove non fosse possibile accedere per eseguire una misura diretta. Lo strumento copre un campo di frequenze fino alle decine di Hz, ha una sensibilità e una dinamica tale da rilevare le vibrazioni indotte dal rumore industriale, dal traffico, dal vento e altro. Questo lavoro è principalmente rivolto alle applicazioni del TIS nel rilevamento delle vibrazioni delle strutture ed è in questo ambito che vengono spiegate le modalità, i limiti e i vantaggi del suo impiego insieme agli errori insiti nella tecnica di misura. Dato che il TIS misura un movimento relativo tra lo stesso strumento e la superficiebersaglio, sono stati valutati gli errori delle vibrazioni dovute alla microsismicità e altre cause ambientali. Vengono infine riportati due preliminari esempi di misura su una struttura edile.
    Description: Regione Lazio, progetto EDISECUR
    Description: Published
    Description: 1-36
    Description: 7TM.Sviluppo e Trasferimento Tecnologico
    Description: JCR Journal
    Keywords: Remote Sensor ; Vibration Detector
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Long-range detection of acoustic vibrations by speckle tracking (2022)
    Details
    Publication Date: 2022-04-06
    Description: When a rough surface is illuminated by a laser beam, it scatters the light, producing a random interference pattern also known as speckle pattern. By imaging the speckle pattern with a line-scan CCD, we are able to measure the acoustic vibrations of a scattering surface, which can be up to 300 m distant. We also show that our instrument can be used as a laser microphone capable of detecting ambient sound such as a human voice.
    Description: Published
    Description: 7805-7809
    Description: 7TM.Sviluppo e Trasferimento Tecnologico
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Tursiops truncatus (Bottlenose Dolphin) - CCSN 02-128 (2022)
    Woods Hole Oceanographic Institution
    Details
    Publication Date: 2022-04-06
    Description: Tursiops truncatus (Bottlenose Dolphin) - CCSN 02-128 - male - 2.93 m - Pelvic location - Cape Cod Stranding Network
    Repository Name: Woods Hole Open Access Server
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    Science and Citizen Collaboration as Good Example of Geoethics for Recovering a Natural Site in the Urban Area of Rome (Italy) (2022)
    MDPI
    Details
    Publication Date: 2022-04-11
    Description: Natural sites in urban spaces can have a key role in citizen well-being, providing fundamental ecosystem services to the population and assuring a multitude of benefits. Therefore, cities should guarantee a number of green areas and their conservation in time as an essential part of urban architecture. In this framework, cooperation between scientists, decision makers and citizens is critical to ensure the enhancement of green public spaces. Social and scientific communities are called to work in a tuned way to combine scientific knowledge and methods to local socio-economic contexts, driven by the values of geoethics. The Bullicante Lake case study, discussed in this work, represents an example of application of geoethical values, such as inclusiveness, sharing, sustainability and conservation of bio- and geodiversity. This urban lake in Rome appeared following illegal excavation works in 1992 and remained closed until 2016 favouring re-naturalization processes. Over time, this site was often threatened by pending actions for building. The aim of this study was to highlight how fruitful cooperation between science and citizens is able to transform a degraded urban area into a place of knowledge, recreation, enjoyment and eco-systemic preservation. Moreover, on the basis of this experience, the authors proposed a generalised approach/strategy to be developed and applied in other contexts. The active involvement of citizens and the cooperation among scientists, artists and institutions were able to redress opportunistic behaviours well by preventing site degradation and its improper use, favouring environmental safeguarding and making possible the site’s recognition as a natural monument. The results of these actions led to the improved quality of citizen life, showing an excellent example of virtuous cooperation between science and society.
    Description: Published
    Description: 4429
    Description: 1TM. Formazione
    Description: 2TM. Divulgazione Scientifica
    Description: JCR Journal
    Keywords: geoethics ; conservation ; education ; citizen participation ; ecosystems ; urban lake ; green areas ; Rome ; 05.09. Miscellaneous ; 05.03. Educational, History of Science, Public Issues
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Bollettino Sismico Italiano 2015 (2022)
    INGV
    Details
    Publication Date: 2022-04-11
    Description: L’Istituto Nazionale di Geofisica e Vulcanologia (INGV) riceve, nella Sala di Sorveglianza Sismica e Centro Allerta Tsunami di Roma, i segnali in tempo reale da centinaia di stazioni sismiche distribuite sul territorio nazionale. Entro due minuti dall’occorrenza di un qualsiasi terremoto, appositi sistemi automatici forniscono una prima valutazione dei parametri ipocentrali. Due sismologi, sempre presenti nella sala operativa della sede centrale, controllano le informazioni ottenute e, per i terremoti sopra una determinata soglia di magnitudo (ML ≥ 2.5), comunicano alla Sala Situazione Italia della Protezione Civile i dati elaborati, in media in circa 12 minuti (massimo entro 30 minuti) [Margheriti et al., 2021]. La valutazione definitiva dei parametri ipocentrali di tutti i terremoti, dai più grandi avvertiti in vaste aree del territorio ai più piccoli rilevati solo da pochi strumenti, è demandata a un’analisi più accurata svolta in un secondo tempo, ormai da alcuni decenni, da un gruppo di analisti specializzati nell’interpretazione dei segnali sismici. Gli analisti sismologi del Bollettino Sismico Italiano revisionano tutti i dati registrati dalle stazioni della Rete Sismica Nazionale (RSN) dell’INGV e riconoscono la presenza di terremoti attraverso un’analisi diretta delle forme d’onda. In tal modo l’analista rileva il tempo d’arrivo delle onde sismiche ai vari sensori e valuta l’ampiezza delle oscillazioni e la direzione del moto del suolo; questi parametri, utilizzati da apposite procedure di calcolo, consentono di localizzare ogni terremoto e di valutare la magnitudo associata. Le informazioni così ottenute confluiscono nel database che l’INGV gestisce e che mette a disposizione della comunità1. Questa pubblicazione ha come scopo quello di far conoscere un prodotto dell’Istituto Nazionale di Geofisica e Vulcanologia, Il Bollettino Sismico Italiano (BSI), con particolare riferimento all’anno 2015. Saranno delineate le principali caratteristiche della sismicità naturale e quella di origine antropica registrata in Italia nel corso dell’anno esaminato.
    Description: Published
    Description: 1-48
    Description: 4IT. Banche dati
    Description: JCR Journal
    Keywords: Bollettino Sismico Italiano 2015 ; Italian Seismic Bulletin 2015 ; sequences and seismic swarms ; explosion ; 04. Solid Earth::04.06. Seismology
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Building back better : the COVID-19 pandemic and transport policy implications for a developing megacity (2022)
    Details
    Publication Date: 2022-04-14
    Description: The COVID-19 pandemic has affected human mobility via lockdowns, social distancing rules, home quarantines, and the full or partial suspension of transportation. Evidence-based policy recommendations are urgently needed to ensure that transport systems have resilience to future pandemic outbreaks, particularly within Global South megacities where demand for public transport is high and reduced access can exacerbate socio-economic inequalities. This study focuses on Metro Manila - a characteristic megacity that experienced one of the most stringent lockdowns worldwide. It analyzes aggregated cell phone and GPS data from Google and Apple that provide a comprehensive representation of mobility behavior before and during the lockdown. While significant decreases are observed for all transport modes, public transport experienced the largest drop (-74.5 %, on average). The study demonstrates that: (i) those most reliant on public transport were disproportionately affected by lockdowns; (ii) public transport was unable to fulfil its role as public service; and, (iii) this drove a paradigm shift towards active mobility. Moving forwards, in the short-term policymakers must promote active mobility and prioritize public transport to reduce unequal access to transport. Longer-term, policymakers must leverage the increased active transport to encourage modal shift via infrastructure investment, and better utilize big data to support decision-making.
    Keywords: ddc:380
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: English
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    Beyond food for thought : directing sustainability transitions research to address fundamental change in agri-food systems (2022)
    Details
    Publication Date: 2022-04-14
    Description: Dominant agricultural and food systems lead to continuous resource depletion and unacceptable environmental and social impacts. While current calls for changing agrifood systems are increasingly framed in the context of sustainability transitions, they rarely make an explicit link to transition studies to address these systemic challenges, nor do transition scholars sufficiently address agri-food systems, despite their global pertinence. From this viewpoint, we illustrate several gaps in the agri-food systems debate that sustainability transition studies could engage in. We propose four avenues for research in the next decade of transition research on agri-food systems: 1) Crossscale dynamics between coupled systems; 2) Social justice, equity and inclusion; 3) Sustainability transitions in low- and middle-income countries; 4) Cross-sectoral governance and system integration. We call for a decade of new transition research that moves beyond single-scale and sector perspectives toward more inclusive and integrated analyses of food system dynamics.
    Keywords: ddc:600
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: English
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    Coupling circularity performance and climate action : from disciplinary silos to transdisciplinary modelling science (2022)
    Details
    Publication Date: 2022-04-14
    Description: Technological breakthroughs and policy measures targeting energy efficiency and clean energy alone will not suffice to deliver Paris Agreement-compliant greenhouse gas emissions trajectories in the next decades. Strong cases have recently been made for acknowledging the decarbonisation potential lying in transforming linear economic models into closed-loop industrial ecosystems and in shifting lifestyle patterns towards this direction. This perspective highlights the research capacity needed to inform on the role and potential of the circular economy for climate change mitigation and to enhance the scientific capabilities to quantitatively explore their synergies and trade-offs. This begins with establishing conceptual and methodological bridges amongst the relevant and currently fragmented research communities, thereby allowing an interdisciplinary integration and assessment of circularity, decarbonisation, and sustainable development. Following similar calls for science in support of climate action, a transdisciplinary scientific agenda is needed to co-create the goals and scientific processes underpinning the transition pathways towards a circular, net-zero economy with representatives from policy, industry, and civil society. Here, it is argued that such integration of disciplines, methods, and communities can then lead to new and/or structurally enhanced quantitative systems models that better represent critical industrial value chains, consumption patterns, and mitigation technologies. This will be a crucial advancement towards assessing the material implications of, and the contribution of enhanced circularity performance to, mitigation pathways that are compatible with the temperature goals of the Paris Agreement and the transition to a circular economy.
    Keywords: ddc:600
    Repository Name: Wuppertal Institut für Klima, Umwelt, Energie
    Language: English
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    Estimating the Rate of Change of Stratospheric Ozone using Deep Neural Networks (2020)
    Earth and Space Science Open Archive (ESSOAr)
    In:  EPIC3AGU 2020 Fall Meeting, San Francisco, 2020-12-01-2020-12-17Estimating the Rate of Change of Stratospheric Ozone using Deep Neural Networks, AGU Fall Meeting 2020, Earth and Space Science Open Archive (ESSOAr)
    Details
    Publication Date: 2022-04-14
    Description: Due to the intensive ozone research in recent decades, the processes that influence stratospheric ozone are well understood. The chemistry and transport model ATLAS was developed to simulate the chemistry and transport of stratospheric ozone globally. The chemical rate of change of ozone is calculated at each model point and time step of the model by solving a system of differential equations that requires 55 input parameters (chemical species, temperatures, ...). But the computational e!ort to solve this complex system of differential equations is very high, and with respect to the overall limited computation time, this prevents the inclusion of ozone chemistry into ESMs. This project proposes a data-driven machine learning approach to predict the rate of change of stratospheric ozone. To derive a data set from modelled data, ATLAS was run for several short model runs. The rate of change of ozone and 55 parameters were stored at each model point and time step. By observing the co-variances of the high-dimensional feature-space, a large data set with reduced dimensionality has been created. A supervised learning algorithm used this data set of input and output pairs to train a deep feed- forward neural network (NN). This involved the identification and optimisation of several hyperparameters and to find a well- functioning combination of depth (number of layers) and width (number of neurons per layer). In this way, the NN model capacity is optimised with respect to the data itself. To evaluate this approach, the results were compared with another data-driven approach called SWIFT. The SWIFT model employs a repro-modelling approach that uses polynomials to approximate the rate of change of ozone. The resulting NN model is not only capable of learning the context of an eleven-dimensional hyperplane, but also improves the RMSE by about one order of magnitude compared to SWIFT’s previous polynomial approach. In addition, the deviations of the predictions at the boundaries (altitude and latitude) are significantly lower, which is a challenge for the polynomial approach. Only fully coupled ozone climate set ups are able to consider the complex interactions of the stratospheric ozone layer and climate. This is a step towards a computationally very fast but accurate application of an interactive ozone scheme in climate models.
    Repository Name: EPIC Alfred Wegener Institut
    Type: Conference , notRev
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    A framework for drinking water basin protection (2021)
    Details
    Publication Date: 2022-04-01
    Description: Many countries have applied many measures, including preventing inappropriate activities in areas where drinking water is abstracted to protect drinking water resources. However, reaching good water quality based on human health has not been achieved in drinking water basins. Drinking‐Water Protected Areas Determination has been defined as a powerful protection method to restrict inappropriate activities affecting water quality and quantity. These areas are determined based on basin properties to provide sustainable drinking water management. This study aims to present a framework for drinking water protection by giving methodological study steps. Strengths, deficiencies and inadequacies in drinking water protection practices were shown by examining the implementations of Turkey and European Union member countries. Thus, by adding new methods to these applications, a standard approach was created to be applied to each different drinking water basin.
    Keywords: ddc:363.61 ; ddc:628.1
    Language: English
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    Adoption of multiple sustainable land management practices among irrigator rural farm households of Ethiopia (2021)
    John Wiley & Sons, Ltd. | Chichester, UK
    Details
    Publication Date: 2022-04-01
    Description: Using a household and plot‐level survey conducted in Ethiopia, this study analyses the difference in farmers' adoption of sustainable land management (SLM) practices between their rainfed and irrigated plots. The paper also investigates the varying influence of different types of irrigation water management systems and associated irrigation technologies on the adoption of SLM practices in irrigated plots. After controlling for heterogeneity among different irrigation water management systems and technologies, we found that access to irrigation play major role in enhancing farmers' motivation to adopt more SLM practices. Furthermore, the combined effect of irrigation water management system and irrigation technology on type and number of SLM practices adopted is quite varied and very significant. The evidence highlights that farmers adopt more SLM practices in their plots with pump irrigation compared with those plots where gravity irrigation is applied because pump irrigation systems enhance complementarities with SLM practices. Finally, the findings underscore that the type of irrigation water management and the irrigation technology applied play an important role in restoring degraded lands and maintaining soil fertility, even when farmers' adoption of irrigation was not explicitly triggered by concerns for soil health.
    Description: Center for Development Research (ZEF), University of Bonn
    Description: CGIAR Research Program on Water, Land, and Ecosystems
    Description: Deutscher Akademischer Austauschdienst (DAAD) http://dx.doi.org/10.13039/501100001655
    Description: Dr. Hermann Eiselen Doctoral Program of the Foundation Fiat
    Description: Federal Ministry for Economic Cooperation and Development (BMZ) of Germany, The Water‐Energy‐Food Nexus: Global, Basin and Local Case Studies of Resource Use Efficiency Under Growing Natural Resource Scarcity
    Keywords: ddc:631
    Language: English
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    Lagrangian Coherent Structures and Vortex Formation in High Spatiotemporal‐Resolution Satellite Winds of an Atmospheric Kármán Vortex Street (2021)
    Details
    Publication Date: 2022-04-01
    Description: Recent advances in geostationary imaging have enabled the derivation of high spatiotemporal‐resolution cloud‐motion winds for the study of mesoscale unsteady flows. Due to the general absence of ground truth, the quality assessment of satellite winds is challenging. In the current limited practice, straightforward plausibility checks on the smoothness of the retrieved wind field or tests on aggregated trends such as the mean velocity components are applied for quality control. In this study, we demonstrate additional diagnostic tools based on feature extraction from the retrieved velocity field. Lagrangian Coherent Structures (LCS), such as vortices and transport barriers, guide and constrain the emergence of cloud patterns. Evaluating the alignment of the extracted LCS with the observed cloud patterns can potentially serve as a test of the retrieved wind field to adequately explain the time‐dependent dynamics. We discuss the suitability and expressiveness of direct, geometry‐based, texture‐based, and feature‐based flow visualization methods for the quality assessment of high spatiotemporal‐resolution winds through the real‐world example of an atmospheric Kármán vortex street and its laboratory archetype, the 2D cylinder flow.
    Description: Key Points: Recently developed high‐cadence geostationary satellite winds enable the Lagrangian analysis of unsteady island wake flows. Good correspondence between Lagrangian Coherent Structures and observed cloud patterns indirectly confirms the fidelity of fluid dynamics. Discussion of benefits and pitfalls of common flow visualization techniques for the analysis of fluid dynamics.
    Description: Swiss National Science Foundation
    Description: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347
    Description: Deutsche Forschungsgemeinschaft http://dx.doi.org/10.13039/501100001659
    Description: https://doi.org/10.5281/zenodo.3534276
    Description: https://www.avl.class.noaa.gov/
    Description: https://github.com/tobguent/vislcs-guadalupe
    Keywords: ddc:550.724
    Language: English
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    Ocean Model Formulation Influences Transient Climate Response (2021)
    Details
    Publication Date: 2022-04-01
    Description: The transient climate response (TCR) is 20% higher in the Alfred Wegener Institute Climate Model (AWI‐CM) compared to the Max Planck Institute Earth System Model (MPI‐ESM) whereas the equilibrium climate sensitivity (ECS) is by up to 10% higher in AWI‐CM. These results are largely independent of the two considered model resolutions for each model. The two coupled CMIP6 models share the same atmosphere‐land component ECHAM6.3 developed at the Max Planck Institute for Meteorology (MPI‐M). However, ECHAM6.3 is coupled to two different ocean models, namely the MPIOM sea ice‐ocean model developed at MPI‐M and the FESOM sea ice‐ocean model developed at the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI). A reason for the different TCR is related to ocean heat uptake in response to greenhouse gas forcing. Specifically, AWI‐CM simulations show stronger surface heating than MPI‐ESM simulations while the latter accumulate more heat in the deeper ocean. The vertically integrated ocean heat content is increasing slower in AWI‐CM model configurations compared to MPI‐ESM model configurations in the high latitudes. Weaker vertical mixing in AWI‐CM model configurations compared to MPI‐ESM model configurations seems to be key for these differences. The strongest difference in vertical ocean mixing occurs inside the Weddell and Ross Gyres and the northern North Atlantic. Over the North Atlantic, these differences materialize in a lack of a warming hole in AWI‐CM model configurations and the presence of a warming hole in MPI‐ESM model configurations. All these differences occur largely independent of the considered model resolutions.
    Description: Plain Language Summary: The transient climate response (TCR) describes how strongly near‐surface temperatures warm in response to gradually increasing greenhouse‐gas levels. Here we investigate the role of the ocean which takes up heat and thereby delays the surface warming. Two models of the Coupled Model Intercomparison Project Phase 6 (CMIP6), the Alfred Wegener Institute Climate Model (AWI‐CM) and the Max Planck Institute Earth System Model (MPI‐ESM), which use the same atmosphere model but different ocean models are selected for this study. In AWI‐CM the upper ocean layers heat faster than in MPI‐ESM, while the opposite is true for the deep ocean. As a consequence, the TCR is 20% stronger in AWI‐CM compared to MPI‐ESM. We find that weaker vertical ocean mixing in AWI‐CM compared to MPI‐ESM, especially over the northern North Atlantic and the Weddell and Ross Gyres, is key for these differences. Our findings corroborate the importance of realistic ocean mixing in climate models when it comes to getting the strength and timing of climate change right.
    Description: Key Points: The transient climate response in two coupled models with the same atmosphere but different ocean components differs by 20%. The upper (deeper) ocean heats faster (slower) in AWI‐CM compared to MPI‐ESM, independent of model resolution. Vertical mixing in the northern North Atlantic and the Weddell and Ross Gyres appears to be key for these differences.
    Description: Bundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347
    Description: German Climate Computing Centre (DKRZ)
    Description: Federal Ministry of Education and Research of Germany
    Description: Helmholtz Association http://dx.doi.org/10.13039/501100009318
    Description: https://esgf-data.dkrz.de/projects/cmip6-dkrz/
    Keywords: ddc:551.6
    Language: English
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    A site formation model for Cuncaicha rock shelter: Depositional and postdepositional processes at the high‐altitude keysite in the Peruvian Andes (2021)
    Details
    Publication Date: 2022-04-01
    Description: We report results from geoarchaeological investigations at Cuncaicha rock shelter (4480 m above sea level) in the high Andes of southern Peru. Using field observations, geomorphological, micromorphological, micro‐Fourier transform infrared spectroscopy, Bayesian modeling of radiocarbon ages, and archaeological data, we analyzed the entire stratigraphic sequence to determine depositional and postdepositional processes and agents to assess the impact of bioturbation and to correlate the deposits with regional paleoenvironmental information. The archaeological record is represented well on a microscale, and bioturbation has not destroyed the stratigraphic integrity. The Terminal Pleistocene sediments that contain the oldest archaeological material at the site, dating to ~12.3–11.1 ka, are especially well preserved and capped by a layer of tufa. Depositional changes from autochthonous carbonate precipitation during the Terminal Pleistocene toward allochthonous aeolian sedimentation in the Early Holocene reflect changing environmental and climatic conditions. Formation of a soil during the Late‐Middle Holocene caused postdepositional alterations and likely correlates to variable environmental conditions. We use these results to formulate a site formation model for Cuncaicha rock shelter that integrates archaeological, chronological, and paleoenvironmental data.
    Description: Deutsche Forschungsgemeinschaft, Germany http://dx.doi.org/10.13039/501100001659
    Description: National Science Foundation, United States
    Keywords: ddc:551.447 ; ddc:558
    Language: English
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    Is the soil moisture precipitation feedback enhanced by heterogeneity and dry soils? A comparative study (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-01
    Description: The interaction between the land surface and the atmosphere is a crucial driver of atmospheric processes. Soil moisture and precipitation are key components in this feedback. Both variables are intertwined in a cycle, that is, the soil moisture – precipitation feedback for which involved processes and interactions are still discussed. In this study the soil moisture – precipitation feedback is compared for the sempiternal humid Ammer catchment in Southern Germany and for the semiarid to subhumid Sissili catchment in West Africa during the warm season, using precipitation datasets from the Climate Hazards Group InfraRed Precipitation with Station data (CHIRPS), from the German Weather Service (REGNIE) and simulation datasets from the Weather Research and Forecasting (WRF) model and the hydrologically enhanced WRF‐Hydro model. WRF and WRF‐Hydro differ by their representation of terrestrial water flow. With this setup we want to investigate the strength, sign and variables involved in the soil moisture – precipitation feedback for these two regions. The normalized model spread between the two simulation results shows linkages between precipitation variability and diagnostic variables surface fluxes, moisture flux convergence above the surface and convective available potential energy in both study regions. The soil moisture – precipitation feedback is evaluated with a classification of soil moisture spatial heterogeneity based on the strength of the soil moisture gradients. This allows us to assess the impact of soil moisture anomalies on surface fluxes, moisture flux convergence, convective available potential energy and precipitation. In both regions the amount of precipitation generally increases with soil moisture spatial heterogeneity. For the Ammer region the soil moisture – precipitation feedback has a weak negative sign with more rain near drier patches while it has a positive signal for the Sissili region with more rain over wetter patches. At least for the observed moderate soil moisture values and the spatial scale of the Ammer region, the spatial variability of soil moisture is more important for surface‐atmosphere interactions than the actual soil moisture content. Overall, we found that soil moisture heterogeneity can greatly affect the soil moisture – precipitation feedback.
    Description: WRF and WRF‐hydro model simulations are used to determine the sign and analyse the mechanisms of the soil moisture ‐ precipitation feedback for the sempiternal humid Ammer catchment in Southern Germany and for the semiarid to subhumid Sissili catchment in West Africa during the warm season. The generation of moist convection is favoured over surfaces with moderately high soil moisture gradients in the Ammer region, while for the Sissili region the location of precipitation tends to be related to areas with high soil moisture gradients. For the Ammer region the soil moisture – precipitation feedback has a weak negative sign with more rain near drier patches while it has a positive signal for the Sissili region with more rain over wetter patches.
    Description: Untersuchung des Klimas des südlichen Afrikas – ein Brückenschlag vom frühen Holozän bis heute
    Description: Transregional Collaborative Research Center
    Keywords: ddc:551.57 ; ddc:631.4
    Language: English
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    The Role of Moisture Conveyor Belts for Precipitation in the Atacama Desert (2021)
    Details
    Publication Date: 2022-04-01
    Description: In the hyperarid Atacama Desert in northern Chile, rare precipitation events can leave long‐lasting geomorphological traces and have strong impacts on biota. While moisture conveyor belts (MCBs) and atmospheric rivers (ARs) have been associated with extreme precipitation in semiarid regions, their role for the Atacama Desert has not been previously investigated. This study reveals that about four MCBs per year make landfall in the Atacama Desert. According to simulated precipitation, 40–80% of the total precipitation between the coast and the Andean foothills is associated with MCBs. A case study reveals an elevated moisture transport decoupled from the maritime boundary layer, which is generalized by a composite analysis. Back trajectories reveal the Amazon Basin as the main source of moisture. MCB landfall times are derived from the AR catalog by Guan and Waliser (2015), https://doi.org/10.1002/2015jd024257. Implications of the results on paleoclimate reconstructions are discussed.
    Description: Plain Language Summary: In the extremely dry Atacama Desert in northern Chile, rare rain events can trigger landscape alterations and have strong impacts on various life forms. Traces of such events are conserved within the desert soil over long time periods throughout the enduring dryness. Such traces constitute climate archives, which can be excavated and explored. Understanding particular conditions, which lead to extreme precipitation events is necessary to interpret such archives, reconstruct climate history, and explore thresholds of life at the dry limit. In this study, the role of a weather phenomenon called moisture conveyor belt (MCB) is quantified for the first time for the Atacama Desert. It is demonstrated that depending on region, 40–80% of the total rainfall is associated with these phenomena. In contrast to atmospheric river characteristics reported for midlatitudes, a unique vertical structure with an elevated moisture transport independent of the near‐surface layer is discovered here. Even though the identified MCBs approach the Atacama Desert from northwesterly directions across the Pacific Ocean, the associated moisture mostly originates from the Amazon Basin.
    Description: Key Points: For most parts of the Atacama Desert, more than half of the total precipitation is related to moisture conveyor belts (MCBs). In contrast to midlatitudes, main moisture transport takes place in mid‐tropospheric layers decoupled from the maritime boundary layer. The main origin of the MCB‐related moisture is found to be the Amazon Basin.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: https://www.crc1211db.uni-koeln.de/search/view.php?dataID=38
    Description: http://www.cr2.cl/datos-de-precipitacion/
    Description: http://explorador.cr2.cl/
    Keywords: ddc:551.6
    Language: English
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    Spatial and Temporal Variability in Concentration‐Discharge Relationships at the Event Scale (2021)
    Details
    Publication Date: 2022-04-01
    Description: The analysis of concentration‐discharge (C‐Q) relationships from low‐frequency observations is commonly used to assess solute sources, mobilization, and reactive transport processes at the catchment scale. High‐frequency concentration measurements are increasingly available and offer additional insights into event‐scale export dynamics. However, only few studies have integrated inter‐annual and event‐scale C‐Q relationships. Here, we analyze high‐frequency measurements of specific conductance (EC), nitrate (NO3‐N) concentrations and spectral absorbance at 254 nm (SAC254, as a proxy for dissolved organic carbon) over a two year period for four neighboring catchments in Germany ranging from more pristine forested to agriculturally managed settings. We apply an integrated method that adds a hysteresis term to the established power law C‐Q model so that concentration intercept, C‐Q slope and hysteresis can be characterized simultaneously. We found that inter‐event variability in C‐Q hysteresis and slope were most pronounced for SAC254 in all catchments and for NO3‐N in forested catchments. SAC254 and NO3‐N event responses in the smallest forested catchment were closely coupled and explainable by antecedent conditions that hint to a common near‐stream source. In contrast, the event‐scale C‐Q patterns of EC in all catchments and of NO3‐N in the agricultural catchment without buffer zones around streams were less variable and similar to the inter‐annual C‐Q relationship indicating a homogeneity of mobilization processes over time. Event‐scale C‐Q analysis thus added key insights into catchment functioning whenever the inter‐annual C‐Q relationship contrasted with event‐scale responses. Analyzing long‐term and event‐scale behavior in one coherent framework helps to disentangle these scattered C‐Q patterns.
    Description: Key Points: We compare event‐scale and inter‐annual concentration‐discharge relationships in four adjoined catchments with contrasting land use. The variability of event‐scale C‐Q relationships was shaped by land use and antecedent conditions for biogeochemically reactive but not for geogenic solutes. For biogeochemically reactive solutes, event‐scale C‐Q patterns can contrast the inter‐annual pattern obtained from all observations.
    Description: Helmholtz Association http://dx.doi.org/10.13039/501100009318
    Description: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347
    Keywords: ddc:551.48
    Language: English
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    Investigating Middle Palaeolithic subsistence: zooarchaeological perspectives on the potential character of hominin climate refugia in Greece (2021)
    Details
    Publication Date: 2022-04-01
    Description: It has long been proposed that during Pleistocene climatic perturbations the Balkan peninsula sustained refugial areas for fauna, flora, and potentially, hominins. In this study, we explore Middle Palaeolithic subsistence at the peninsula's southern end, Greece, and discuss how the evidence contributes to our understanding of the region's character as a refugium. We present new data from the recent reanalysis of the fauna from Asprochaliko rockshelter and the ongoing zooarchaeological investigations at Lakonis Cave 1 and compare them with published analyses from Klissoura Cave 1. We employ taxonomic abundance and diversity indices, as well as mortality profiles, to investigate hominin prey choice. Additional taphonomic observations provide further information on carcass exploitation. We examine changes in the faunal composition of the three sites in an attempt to identify the extent to which climate might have influenced resource availability and diversity in the region, stimulating resource intensification or diversification processes. Our results suggest that Middle Palaeolithic hominins consistently acquired high‐ranked prey through time. However, interregional differences in resource exploitation indicate that local topography and microclimate mediated prey choice and availability.
    Description: Institute for Aegean Prehistory http://dx.doi.org/10.13039/100001182
    Description: Senckenberg Gesellschaft für Naturforschung
    Keywords: ddc:560
    Language: English
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    How to Find Aquifer Statistics Utilizing Pumping Tests? Two Field Studies Using welltestpy (2021)
    Blackwell Publishing Ltd | Malden, US
    Details
    Publication Date: 2022-04-01
    Description: We present a workflow to estimate geostatistical aquifer parameters from pumping test data using the Python package welltestpy. The procedure of pumping test analysis is exemplified for two data sets from the Horkheimer Insel site and from the Lauswiesen site, Germany. The analysis is based on a semi‐analytical drawdown solution from the upscaling approach Radial Coarse Graining, which enables to infer log‐transmissivity variance and horizontal correlation length, beside mean transmissivity, and storativity, from pumping test data. We estimate these parameters of aquifer heterogeneity from type‐curve analysis and determine their sensitivity. This procedure, implemented in welltestpy, is a template for analyzing any pumping test. It goes beyond the possibilities of standard methods, for example, based on Theis' equation, which are limited to mean transmissivity and storativity. A sensitivity study showed the impact of observation well positions on the parameter estimation quality. The insights of this study help to optimize future test setups for geostatistical aquifer analysis and provides guidance for investigating pumping tests with regard to aquifer statistics using the open‐source software package welltestpy.
    Description: Article impact statement: We present a workflow to infer parameters of subsurface heterogeneity from pumping test data exemplified at two sites using welltestpy.
    Description: German Federal Environmental Foundation (DBU) http://dx.doi.org/10.13039/100007636
    Keywords: ddc:551.49
    Language: English
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    Environmental Regulation of the Nitrogen Supply, Mean Trophic Position, and Trophic Enrichment of Mesozooplankton in the Mekong River Plume and Southern South China Sea (2021)
    Details
    Publication Date: 2022-04-01
    Description: The mean trophic position (TP) of mesozooplankton largely determines how much mass and energy is available for higher trophic levels like fish. Unfortunately, the ratio of herbivores to carnivores in mesozooplankton is difficult to identify in field samples. Here, we investigated changes in the mean TP of mesozooplankton in a highly dynamic environment encompassing four distinct habitats in the southern South China Sea: the Mekong River plume, coastal upwelling region, shelf waters, and offshore oceanic waters. We used a set of variables derived from bulk and amino acid nitrogen stable isotopes from particulate organic matter and four mesozooplankton size fractions to identify changes in the nitrogen source and TP of mesozooplankton across these habitats. We found clear indications of a shift in N sources for biological production from nitrate in near‐coastal waters with shallow mixed layer depths toward an increase in diazotroph‐N inputs in oceanic waters with deep mixed layer depths where diazotrophs shaped the phytoplankton community. The N source shift was accompanied by a lengthening of the food chain (increase in the TP). This may provide further support for the connection between diazotrophy and the indirect routing of N through the marine food web. Our combined bulk and amino acid δ15N approach also allowed us to estimate the trophic enrichment (TE) of mesozooplankton across the entire regional ecosystem. When put in the context of literature values, a high TE of 5.1‰ suggested a link between ecosystem heterogeneity and the less efficient transfer of mass and energy across trophic levels.
    Description: Plain Language Summary: Zooplankton are one of the central pillars of the marine food web and form an important link between the production of organic matter by phytoplankton and biomass at higher trophic levels (e.g., fish). Of particular interest are mesozooplankton (0.2–20 mm in size), which encompass a diverse assemblage of animals utilizing a range of feeding strategies, including herbivory, omnivory, and carnivory. Since mass and energy are lost with each trophic step, their prevailing feeding strategy determines the availability of mass and energy to the upper food web. The exact relationship between carnivores and herbivores in mesozooplankton has so far only been studied with complex experiments or in homogenous environments. We have now resolved zooplankton feeding relationships in a highly dynamic marine environment. Specifically, we used stable nitrogen isotopes in amino acids and bulk organic matter in combination with a habitat‐delineating method for phytoplankton to directly determine the ratio of carnivores to herbivores in zooplankton from dynamic habitats in the South China Sea. The mass and energy transfer across trophic levels is less efficient in such variable marine environments compared to stable open ocean systems. These findings represent a big step toward understanding the dynamics of planktonic food webs in general.
    Description: Key Points: Trophic structure of mesozooplankton is regulated by similar environmental factors such as phytoplankton assemblages. Diazotrophy and nutrient availability correlated with enhanced mesozooplankton carnivory in a complex tropical marine ecosystem. Mass and energy transfer across trophic levels of planktonic food webs are less efficient in spatially and temporally variable ecosystems.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: National Foundation for Science and Technology Development (NAFOSTED) http://dx.doi.org/10.13039/100007224
    Description: National Aeronautics and Space Administration (NASA) http://dx.doi.org/10.13039/100000104
    Description: Schmidt Ocean Institute
    Description: National Science Foundation (NSF) http://dx.doi.org/10.13039/100000001
    Description: https://doi.org/10.5061/dryad.bk3j9kdbv
    Keywords: ddc:577.7
    Language: English
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    The HydroEcoSedimentary tool: An integrated approach to characterise interstitial hydro‐sedimentary and associated ecological processes (2021)
    John Wiley & Sons, Ltd. | Chichester, UK
    Details
    Publication Date: 2022-04-01
    Description: Increased deposition of fine sediments in rivers and streams affects a range of key ecosystem processes across the sediment–water interface, and it is a critical aspect of river habitat degradation and restoration. Understanding the mechanisms leading to fine sediment accumulation along and across streambeds and their effect on ecological processes is essential for comprehending human impacts on river ecosystems and informing river restoration. Here, we introduce the HydroEcoSedimentary tool (HEST) as an integrated approach to assess hydro‐sedimentary and ecologically relevant processes together. The HEST integrates the estimation of sedimentary processes in the interstitial zone, as well as hydraulic, geochemical and ecological assessments, with a focus on brown trout early life stages. Compared to other methods, the HEST expands the possibilities to monitor and quantify fine sediment deposition in streambeds by differentiating between vertical, lateral and longitudinal infiltration pathways, and distinguishing between the depth (upper vs. lower layers) at which interstitial processes occur within the sediment column. By testing the method in two rivers with different degrees of morphological degradation, we detail the possible measurements and uses of the HEST, demonstrate its feasibility and discuss its reliability.
    Description: Alexander von Humboldt‐Stiftung http://dx.doi.org/10.13039/100005156
    Description: Bavarian State Ministry of Science and Arts (Bayerisches Staatsministerium für Wissenschaft und Kunst)
    Keywords: ddc:551.48 ; ddc:550.724
    Language: English
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    The effect of stream shading on the inflow characteristics in a downstream reservoir (2021)
    John Wiley & Sons, Ltd. | Chichester, UK
    Details
    Publication Date: 2022-04-01
    Description: In thermally stratified reservoirs, inflows form density currents according to the interplay between inflow temperature and reservoir stratification. The temperature of inflowing water is affected by catchment properties, including shading by riparian vegetation. We hypothesize that the degree of shading in the catchment can affect the inflow dynamics in downstream reservoirs by changing inflow temperature and consequently the nature of the density current. We test it for a subtropical drinking water reservoir by combining catchment‐scale hydrological and stream temperature modeling with observations of reservoir stratification. We analyze the formation of density currents, defined as under, inter and overflow, for scenarios with contrasting shading conditions in the catchment. Inflow temperatures were simulated with the distributed water‐balance model LARSIM‐WT, which integrates heat‐balance and water temperature. River temperature measurements and simulations are in good agreement with a RMSE of 0.58°C. In simulations using the present state of shading, underflows are the most frequent flow path, 63% of the annual period. During the remaining time, river intrusion form interflows. In a scenario without stream shading, average inflow temperature increased by 2.2°C. Thus, interflows were the most frequent flow path (51%), followed by underflows (34%) and overflows (15%). With this change, we would expect a degradation of reservoir water quality, as overflows promote longer periods of anoxia and nutrient loads would be delivered to the photic zone, a potential trigger for algae blooms. This study revealed a potentially important, yet unexplored aspect of catchment management for controlling reservoir water quality.
    Description: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347
    Description: https://doi.org/10.5281/zenodo.4746288
    Keywords: ddc:628.1 ; ddc:551.48
    Language: English
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    Water Isotopic Signature of Surface Snow Metamorphism in Antarctica (2021)
    Details
    Publication Date: 2022-04-01
    Description: Water isotope ratios of ice cores are a key source of information on past temperatures. Through fractionation within the hydrological cycle, temperature is imprinted in the water isotopic composition of snowfalls. However, this signal of climatic interest is modified after deposition when snow remains at the surface exposed to the atmosphere. Comparing time series of surface snow isotopic composition at Dome C with satellite observations of surface snow metamorphism, we found that long summer periods without precipitation favor surface snow metamorphism altering the surface snow isotopic composition. Using excess parameters (combining D,17O, and 18O fractions) allow the identification of this alteration caused by sublimation and condensation of surface hoar. The combined measurement of all three isotopic compositions could help identifying ice core sections influenced by snow metamorphism in sites with very low snow accumulation.
    Description: Plain Language Summary: Water isotopes in ice core records are often used to reconstruct past climate temperature variations. Classically, the temperature signal is thought to be imprinted in water isotopes of precipitation, and then archived in the ice core as it falls, and in cold areas of Antarctica, piles up for very long period. Here, we show that the surface snow isotopic composition varies in between precipitation events, suggesting that there might be more than one contribution to the isotopic signal in ice core records. This is particularly important for low accumulation sites, where the snow at the surface remains exposed for very long time periods. The combined use of several isotopic ratios in surface snow helps us disentangle the processes that create this signal.
    Description: Key Points: During summer without precipitation, intense snow metamorphism shows a strong water isotopic signature. During summer without precipitation, intense snow metamorphism shows a strong water isotopic signature. The d‐excess and 17O‐excess of the snow is a proxy of snow metamorphism for low accumulation regions.
    Description: FP7 Ideas: European Research Council (FP7 Ideas) http://dx.doi.org/10.13039/100011199
    Description: Foundation Prince Albert of Monaco
    Description: Alexander von Humboldt‐Stiftung (Humboldt‐Stiftung) http://dx.doi.org/10.13039/100005156
    Description: DFG project CLIMAIC
    Description: https://doi.pangaea.de/10.1594/PANGAEA.934273
    Keywords: ddc:551.31 ; ddc:551.9
    Language: English
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    Impact of a large artificial lake on regional climate: A typical meteorological year Meso‐NH simulation results (2021)
    John Wiley & Sons, Ltd. | Chichester, UK
    Details
    Publication Date: 2022-04-01
    Description: Large artificial lakes and reservoirs affect the meteorological regime of the shore area and the local climate takes on a number of new features that were previously absent. This work focuses on the weather impact of the Alqueva reservoir, the largest artificial lake in Western Europe. An extensive set of numerical simulations using Meso‐NH mesoscale atmospheric model coupled with FLake (Freshwater Lake) scheme was carried out. The simulations covered a 12‐month period that was chosen to compose a so‐called Typical Meteorological Year. This artificial time period is meant to represent the typical meteorological conditions in the region and the model results are used to assess the changes in the local climate. To evaluate the raw impact of the reservoir, two different scenarios of simulations were compared: (A) with the reservoir as it exists nowadays and (B) without the reservoir using the older surface dataset. The results show decrease of air temperature during daytime (10–9°C) and nighttime increase (up to 10°C). In nearest towns, daily maximum temperature decreased and daily minimum temperature increased, which refers to milder weather conditions. Alqueva mainly showed suppression in fog formation in the nearby area. Local breeze regime was studied and monthly lake/land breezes were described.
    Description: Large lakes and artificial reservoirs can affect the meteorological regime of their coastal areas and impact the local climate. This work focuses on the weather impact of the Alqueva reservoir, the largest artificial lake in Western Europe, studied on the basis of mesoscale atmospheric modelling data over the 12‐month period composed in a typical meteorological year for the region of interest.
    Description: ALOP project
    Description: COMPETE 2020 ICT project
    Description: Fundação para a Ciência e a Tecnologia http://dx.doi.org/10.13039/501100001871
    Description: TOMAQAPA
    Description: http://mesonh.aero.obs-mip.fr/mesonh54/Download
    Keywords: ddc:551.6
    Language: English
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    Insights into Holocene relative sea‐level changes in the southern North Sea using an improved microfauna‐based transfer function (2021)
    Details
    Publication Date: 2022-04-01
    Description: In light of global warming and rising relative sea level (RSL), detailed reconstructions of RSL histories and their controlling processes are essential in order to manage coastal‐protection challenges. This study contributes to unravelling Holocene RSL change on the East Frisian North Sea coast in high resolution and with a new approach for the German Bight. For the first time, a transfer function (vertical error: 29.7 cm ≙ ~11% of the mean tidal range) for RSL change based on a combined training set of benthic foraminifers and ostracods from the back‐barrier tidal basin of Spiekeroog is applied to the Holocene record of the back‐barrier tidal basin of Norderney. The resulting RSL curve for the Norderney tidal basin is corrected for decompaction and shows a deceleration in RSL rise between 6000 and 5000 cal bp. The smallest possible error envelope (~1 m) results from the good suitability of salt‐marsh layers between 5000 and 4000 cal bp. The RSL curve provides an approach towards the closure of the common data gap of peat‐based curves for the southern North Sea related to a lack of basal peats in the youngest age range, and verifies regional differences in glacial isostatic adjustment.
    Description: Volkswagen Foundation http://dx.doi.org/10.13039/501100001663
    Description: Niedersächsisches Ministerium für Wissenschaft und Kultur http://dx.doi.org/10.13039/501100010570
    Keywords: ddc:551.468
    Language: English
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    Changes in spectral quality of underwater light alter phytoplankton community composition (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-01
    Description: Light is a fundamental resource for phytoplankton. To utilize the available light, most phytoplankton species possess pigments in taxon‐specific combinations and quantities, which in turn result in a specific use of certain wavelengths. This optimizes the light use efficiency, allows for a complementary use of light, and may be an additional driver for community structure. While the effects of light intensity on phytoplankton biomass production and community composition have been intensively studied, here we focused on the effects of specific light spectrum quality (thus light color) on a natural phytoplankton community. In a controlled mesocosm experiment we reduced the supplied wavelength range to its blue, green, or red part of the light spectrum and compared the responses of each treatment to a full spectrum control over 28 d. Highest community growth rates were observed under blue, lowest under red light. Light absorption by the communities showed adaptation toward the supplied wavelength range. Community composition was significantly affected by light quality treatments, driven by Bacillariophyta and Chlorophyta, whereas pigment composition was not. Furthermore, lower species richness but higher evenness occurred when communities were exposed to red light compared to the full spectrum. We expected the response of phytoplankton communities to changes in the light spectrum to be driven by a combination of species sorting and pigment acclimation; however, the effect of species sorting turned out to be stronger. Our study showed that, even if species might acclimate, changes in the available light spectrum affect primary production and phytoplankton community composition.
    Keywords: ddc:579
    Language: English
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    Climate Change Can Accelerate Depletion of Montane Grassland C Stocks (2021)
    Details
    Publication Date: 2022-04-01
    Description: Climate warming and management will likely affect carbon (C) fluxes of montane grassland ecosystems. In this study, we assessed the effect of simultaneous warming (+2°C) and decreased precipitation (−25%) on carbon exchange of montane grasslands in S‐Germany by translocating large intact plant‐soil cores from a high altitude to a low altitude site. Cores received two common grassland management regimes: intensive (4–5 cuts and slurry application) and extensive (1–2 cuts and slurry application). Diurnal patterns of net ecosystem exchange (NEE) and total ecosystem respiration (Reco) were measured over 1.5 years in 2–3 weeks intervals during the snow free period. Additional data on environmental controls, that is, photosynthetic active radiation, grass height and soil moisture and temperature, were used to develop empirical models to estimate daily and annual fluxes of gross primary production (GPP) and Reco. Considering the 2 years period (2014 and 2015), we found that, under warmer and slightly drier conditions, both GPP and Reco significantly (p 〈 0.01) increased (up to 20%) but with a higher temperature sensitivity of Reco, particularly in intensive managed grassland. The higher temperature sensitivity of Reco reduced the NEE by 0.7 t C ha−1 yr−1 for both extensive and intensive management, respectively. Considering additional carbon inputs via slurry and exports via harvest (i.e., annual net ecosystem carbon budget), our results showed that managed grasslands are already a source of C under current climate conditions (1.7–1.8 t ha−1 yr−1) which significantly (p 〈 0.05) increased under climate warming (2.3–2.9 t ha−1 yr−1).
    Description: Key Points: Climate change can accelerate depletion of montane grassland C stocks. Under warmer conditions gross primary production and ecosystem respiration (Reco) increase, but Reco with a higher temperature sensitivity. Adaptation of grassland cutting and manure management regimes can likely reduce ecosystem carbon losses.
    Description: Bundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347
    Description: Deutscher Akademischer Austauschdienst (DAAD) http://dx.doi.org/10.13039/501100001655
    Description: Office of China Postdoc Council
    Description: Alexander von Humboldt‐Stiftung (Humboldt‐Stiftung) http://dx.doi.org/10.13039/100005156
    Description: https://figshare.com/articles/dataset/Data%5Fof%5Fpublication%5FWang%5Fet%5Fal%5Funder%5Freview%5FGBC/14566215
    Keywords: ddc:630 ; ddc:577.22
    Language: English
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    Uncertainty in Aerosol Optical Depth From Modern Aerosol‐Climate Models, Reanalyses, and Satellite Products (2022)
    Details
    Publication Date: 2022-04-01
    Description: Despite the implication of aerosols for the radiation budget, there are persistent differences in data for the aerosol optical depth (τ) for 1998–2019. This study presents a comprehensive evaluation of the large‐scale spatio‐temporal patterns of mid‐visible τ from modern data sets. In total, we assessed 94 different global data sets from eight satellite retrievals, four aerosol‐climate model ensembles, one operational ensemble product, two reanalyses, one climatology and one merged satellite product. We include the new satellite data SLSTR and aerosol‐climate simulations from the Coupled Model Intercomparison Project Phase 6 (CMIP6) and the Aerosol Comparisons between Observations and Models Phase 3 (AeroCom‐III). Our intercomparison highlights model differences and observational uncertainty. Spatial mean τ for 60°N – 60°S ranges from 0.124 to 0.164 for individual satellites, with a mean of 0.14. Averaged τ from aerosol‐climate model ensembles fall within this satellite range, but individual models do not. Our assessment suggests no systematic improvement compared to CMIP5 and AeroCom‐I. Although some regional biases have been reduced, τ from both CMIP6 and AeroCom‐III are for instance substantially larger along extra‐tropical storm tracks compared to the satellite products. The considerable uncertainty in observed τ implies that a model evaluation based on a single satellite product might draw biased conclusions. This underlines the need for continued efforts to improve both model and satellite estimates of τ, for example, through measurement campaigns in areas of particularly uncertain satellite estimates identified in this study, to facilitate a better understanding of aerosol effects in the Earth system.
    Description: Plain Language Summary: Aerosols are known to affect atmospheric processes. For instance, particles emitted during dust storms, biomass burning and anthropogenic activities affect air quality and influence the climate through effects on solar radiation and clouds. Although many studies address such aerosol effects, there is a persistent difference in current estimates of the amount of aerosols in the atmosphere across observations and complex climate models. This study documents the data differences for aerosol amounts, including new estimates from climate‐model simulations and satellite products. We quantify considerable differences across aerosol amount estimates as well as regional and seasonal variations of extended and new data. Further, this study addresses the question to what extent complex climate models have improved over the past decades in light of observational uncertainty.
    Description: Key Points: Present‐day patterns in aerosol optical depth differ substantially between 94 modern global data sets. The range in spatial means from individual satellites is −11% to +17% of the multi‐satellite mean. Spatial means from climate model intercomparison projects fall within the satellite range but strong regional differences are identified.
    Description: Hans‐Ertel‐Center for Weather Research
    Description: Collaborative Research Centre 1211
    Description: Max‐Planck‐Institute for Meteorology
    Keywords: ddc:551.5
    Language: English
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    A Lagrangian Perspective on Stable Water Isotopes During the West African Monsoon (2021)
    Details
    Publication Date: 2022-04-01
    Description: We present a Lagrangian framework for identifying mechanisms that control the isotopic composition of mid‐tropospheric water vapor in the Sahel region during the West African Monsoon 2016. In this region mixing between contrasting air masses, strong convective activity, as well as surface and rain evaporation lead to high variability in the distribution of stable water isotopologues. Using backward trajectories based on high‐resolution isotope‐enabled model data, we obtain information not only about the source regions of Sahelian air masses, but also about the evolution of H2O and its isotopologue HDO (expressed as δD) along the pathways of individual air parcels. We sort the full trajectory ensemble into groups with similar transport pathways and hydro‐meteorological properties, such as precipitation and relative humidity, and investigate the evolution of the corresponding paired {H2O, δD} distributions. The use of idealized process curves in the {H2O, δD} phase space allows us to attribute isotopic changes to contributions from (a) air mass mixing, (b) Rayleigh condensation during convection, and (c) microphysical processes depleting the vapor beyond the Rayleigh prediction, i.e., partial rain evaporation in unsaturated and isotopic equilibration in saturated conditions. Different combinations of these processes along the trajectory ensembles are found to determine the final isotopic composition in the Sahelian troposphere during the monsoon. The presented Lagrangian framework is a powerful tool for interpreting tropospheric water vapor distributions. In the future, it will be applied to satellite observations of {H2O, δD} over Africa and other regions in order to better quantify characteristics of the hydrological cycle.
    Description: Key Points: New Lagrangian framework to attribute variability in {H2O, δD} distributions to air mass mixing and phase changes of water. Application to West African Monsoon season 2016 shows characteristic mixing and precipitation effects along trajectories. New framework can be used for the interpretation of satellite and in‐situ observations, and for model validation in future work.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: Swiss National Science Foundation
    Description: European Space Agency
    Description: Bundesministerium für Bildung und Forschung (BMBF) http://dx.doi.org/10.13039/501100002347
    Description: Ministerium für Wissenschaft, Forschung und Kunst Baden‐Württemberg (MWK) http://dx.doi.org/10.13039/501100003542
    Keywords: ddc:551.5
    Language: English
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    Neanderthals of Porto Selvaggio in southern Italy: lithic industry of Grotta Torre dell'Alto (Nardò, Lecce) (2021)
    Details
    Publication Date: 2022-04-01
    Description: Porto Selvaggio in southern Italy is where the Uluzzian culture was first identified and documented, providing key insights into the transition from the Middle to the Upper Paleolithic. The area has also yielded evidence for continuous occupations by Neanderthals spanning between Marine Isotope Stage (MIS) 5 and 3. Situated in the Natural Regional Park of Porto Selvaggio, different sites were excavated by Borzatti von Löwenstern in the 1960 and 1970s. As one of the initiatives in the research program of the Museo della Preistoria di Nardò, we have revisited the artifact assemblages from these caves. Based on the lithic analysis of production sequences, we document the development of Levallois and laminar methods before MIS 3 when this form of reduction sequence presumably dominated in the region according to the previous research. The review of the lithic assemblages is combined with the contextualization of chronostratigraphy and paleoenvironmental study in the region to consider the possible role that this region had for Neanderthals during unfavorable climatic conditions.
    Description: Nomos – Servizi per la Cultura del Patrimonio
    Description: Ente di Gestione del Parco Naturale Regionale di Portoselvaggio e Palude del Capitano
    Description: Municipality of Nardò
    Keywords: ddc:569.986 ; ddc:551.447
    Language: English
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    Anomalous Reconnection Layer at Earth's Dayside Magnetopause (2021)
    Details
    Publication Date: 2022-04-01
    Description: Observations by the Magnetospheric Multiscale spacecraft (MMS) of an unusual layer, located between the dayside magnetosheath and the magnetosphere, alternating with encounters with the magnetosheath during an extended time period between December 31, 2015 and January 01, 2016, when the interplanetary magnetic field was strongly southward and the Earth's dipole tilt large and negative, are presented. It appears to have been magnetically connected to both magnetosphere and magnetosheath. The layer appears to be located mostly on closed field lines and was bounded by a rotational discontinuity (RD) at its magnetosheath edge and by the magnetosphere on its earthward side. A separatrix layer, with heated magnetosheath electrons streaming unidirectionally along the field lines, was present sunward of the RD. We infer that the layer was started by a dominant reconnection site well north of the spacecraft and that it may have gained additional width, from a large drop in solar wind density and ram pressure, which preceded the beginning of the event by more than an hour. Relative to the magnetosheath, in which the magnetic field was strongly southward, this unusual layer was characterized by a less southward, more dawnward magnetic field of lower magnitude. The plasma density and flow speed in the region were lower than in the magnetosheath, albeit with Alfvénic jetting occurring at the magnetosheath edge as well as at the magnetospheric edge of the layer. The closing of the magnetic field lines requires the existence of another reconnection site, located southward/tailward of MMS.
    Description: Key Points: Magnetopause encounter for strongly southward interplanetary magnetic field, low solar wind Alfvén Mach number, and large dipole tilt. Persistent and broad magnetopause layer with magnetospheric O+ and heated magnetosheath plasma. Inferred dominant reconnection site near northern cusp, far from the Magnetospheric Multiscale spacecraft location.
    Description: MPE
    Description: NASA http://dx.doi.org/10.13039/100000104
    Description: Norwegian Research Council http://dx.doi.org/10.13039/501100005416
    Keywords: ddc:538.7
    Language: English
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    Importance of sources of variability, scales and experimental design: A case study about the effects of biochar and slurry application on soil properties in agricultural silty loam soils (2021)
    Blackwell Publishing Ltd | Oxford, UK
    Details
    Publication Date: 2022-04-01
    Description: In designed experiments, different sources of variability and an adequate scale of measurement need to be considered, but not all approaches in common usage are equally valid. In order to elucidate the importance of sources of variability and choice of scale, we conducted an experiment where the effects of biochar and slurry applications on soil properties related to soil fertility were studied for different designs: (a) for a field‐scale sampling design with either a model soil (without natural variability) as an internal control or with composited soils, (b) for a design with a focus on amendment variabilities, and (c) for three individual field‐scale designs with true field replication and a combined analysis representative of the population of loess‐derived soils. Three silty loam sites in Germany were sampled and the soil macroaggregates were crushed. For each design, six treatments (0, 0.15 and 0.30 g slurry‐N kg−1 with and without 30 g biochar kg−1) were applied before incubating the units under constant soil moisture conditions for 78 days. CO2 fluxes were monitored and soils were analysed for macroaggregate yields and associated organic carbon (C). Mixed‐effects models were used to describe the effects. For all soil properties, results for the loess sites differed with respect to significant contributions of fixed effects for at least one site, suggesting the need for a general inclusion of different sites. Analysis using a multilevel model allowed generalizations for loess soils to be made and showed that site:slurry:biochar and site:slurry interactions were not negligible for macroaggregate yields. The use of a model soil as an internal control enabled observation of variabilities other than those related to soils or amendments. Experiments incorporating natural variability in soils or amendments resulted in partially different outcomes, indicating the need to include all important sources of variability. Highlights Effects of biochar and slurry applications were studied for different designs and mixed‐effects models were used to describe the effects. Including an internal control allowed observation of, e.g., methodological and analytical variabilities. The results suggested the need for a general inclusion of different sites. Analysis using a multilevel model allowed generalizations for loess soils. The results indicated the need to include all important sources of variability.
    Keywords: ddc:631.4
    Language: English
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    Impacts of Drying and Rewetting on the Radiocarbon Signature of Respired CO2 and Implications for Incubating Archived Soils (2021)
    Details
    Publication Date: 2022-04-01
    Description: The radiocarbon signature of respired CO2 (∆14C‐CO2) measured in laboratory soil incubations integrates contributions from soil carbon pools with a wide range of ages, making it a powerful model constraint. Incubating archived soils enriched by “bomb‐C” from mid‐20th century nuclear weapons testing would be even more powerful as it would enable us to trace this pulse over time. However, air‐drying and subsequent rewetting of archived soils, as well as storage duration, may alter the relative contribution to respiration from soil carbon pools with different cycling rates. We designed three experiments to assess air‐drying and rewetting effects on ∆14C‐CO2 with constant storage duration (Experiment 1), without storage (Experiment 2), and with variable storage duration (Experiment 3). We found that air‐drying and rewetting led to small but significant (α 〈 0.05) shifts in ∆14C‐CO2 relative to undried controls in all experiments, with grassland soils responding more strongly than forest soils. Storage duration (4–14 y) did not have a substantial effect. Mean differences (95% CIs) for experiments 1, 2, and 3 were: 23.3‰ (±6.6), 19.6‰ (±10.3), and 29.3‰ (±29.1) for grassland soils, versus −11.6‰ (±4.1), 12.7‰ (±8.5), and −24.2‰ (±13.2) for forest soils. Our results indicate that air‐drying and rewetting soils mobilizes a slightly older pool of carbon that would otherwise be inaccessible to microbes, an effect that persists throughout the incubation. However, as the bias in ∆14C‐CO2 from air‐drying and rewetting is small, measuring ∆14C‐CO2 in incubations of archived soils appears to be a promising technique for constraining soil carbon models.
    Description: Plain Language Summary: Soils play a key role in the global carbon cycle by sequestering carbon from the atmosphere for decades to millennia. However, it is unclear if they will continue to do so as the climate changes. Microbial decomposition of soil organic matter returns carbon back to the atmosphere, and radiocarbon dating of this returning CO2 (∆14C‐CO2) can be used to quantify how long carbon is stored in ecosystems. Incubating archived soils could provide unique insight into soil carbon sequestration potential by quantifying the change in ∆14C‐CO2 over time. However, air‐drying, duration of archiving, and subsequent rewetting of soils may bias estimates of sequestration potential by altering the balance of younger versus older carbon leaving the soil. We compared ∆14C‐CO2 from soils incubated with and without air‐drying and archiving, and found that the air‐dried soils appeared to release slightly older carbon than soils that had never been air‐dried. The amount of time the soils were archived did not have an effect. Since the bias from air‐drying and rewetting was small, incubating archived soils appears to be a promising technique for improving our ability to model soil carbon cycling under global climate change.
    Description: Key Points: ∆14C of CO2 measured in incubations of archived soils provides additional constraints for soil carbon models. Air‐drying and rewetting soils shifted the ∆14C of respired CO2 by 10‰–20‰ independent of the duration of storage. Differences in direction and magnitude of ∆14C‐CO2 shifts between forests and grasslands depended on sampling year and system C dynamics.
    Description: EC, H2020, H2020 Priority Excellent Science, H2020 European Research Council (ERC) http://dx.doi.org/10.13039/100010663
    Description: https://doi.org/10.5281/zenodo.4959705
    Keywords: ddc:551.9 ; ddc:631.41 ; ddc:550.724
    Language: English
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    Do tree species affect decadal changes in soil organic carbon and total nitrogen stocks in Danish common garden experiments? (2021)
    Blackwell Publishing Ltd | Oxford, UK
    Details
    Publication Date: 2022-04-01
    Description: Temperate forest soils are often considered as an important sink for atmospheric carbon (C), thereby buffering anthropogenic CO2 emissions. However, the effect of tree species composition on the magnitude of this sink is unclear. We resampled a tree species common garden experiment (six sites) a decade after initial sampling to evaluate whether forest floor (FF) and topsoil organic carbon (Corg) and total nitrogen (Nt) stocks changed in dependence of tree species (Norway spruce—Picea abies L., European beech—Fagus sylvatica L., pedunculate oak—Quercus robur L., sycamore maple—Acer pseudoplatanus L., European ash—Fraxinus excelsior L. and small‐leaved lime—Tilia cordata L.). Two groups of species were identified in terms of Corg and Nt distribution: (1) Spruce with high Corg and Nt stocks in the FF developed as a mor humus layer which tended to have smaller Corg and Nt stocks and a wider Corg:Nt ratio in the mineral topsoil, and (2) the broadleaved species, of which ash and maple distinguished most clearly from spruce by very low Corg and Nt stocks in the FF developed as mull humus layer, had greater Corg and Nt stocks, and narrow Corg:Nt ratios in the mineral topsoil. Over 11 years, FF Corg and Nt stocks increased most under spruce, while small decreases in bulk mineral soil (esp. in 0–15 cm and 0–30 cm depth) Corg and Nt stocks dominated irrespective of species. Observed decadal changes were associated with site‐related and tree species‐mediated soil properties in a way that hinted towards short‐term accumulation and mineralisation dynamics of easily available organic substances. We found no indication for Corg stabilisation. However, results indicated increasing Nt stabilisation with increasing biomass of burrowing earthworms, which were highest under ash, lime and maple and lowest under spruce. Highlights We studied if tree species differences in topsoil Corg and Nt stocks substantiate after a decade. The study is unique in its repeated soil sampling in a multisite common garden experiment. Forest floors increased under spruce, but topsoil stocks decreased irrespective of species. Changes were of short‐term nature. Nitrogen was most stable under arbuscular mycorrhizal species.
    Description: Deutsche Forschungsgemeinschaff (DFG)
    Keywords: ddc:551.9 ; ddc:631.41
    Language: English
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    Spatial variability in river bed porosity determined by nuclear density gauging: A case study from a French gravel‐bed river (2021)
    Details
    Publication Date: 2022-04-01
    Description: Porosity is one of the key properties of fluvial sediments. It is defined as the ratio of pore volume to total volume. In river science, porosity is often assumed to be spatially constant, which might be a gross simplification of reality. Ignoring the spatial variations in porosity can cause errors in morphological, ecological, hydrological, hydrogeological and sedimentological applications. Although detailed information about spatial porosity variations can be obtained from porosity measurements at field sites, such information has never been collected where these variations might be important. In this study, field porosity measurements were carried out to quantify the magnitude of the spatial porosity variation for four different sedimentological environments of a braided river: a confluence, a tributary delta, a braid bar and a secondary channel. A nuclear density gauge was used for the measurement of porosity. The nuclear density gauge proved to be a time‐saving and labour‐saving technique that produces accurate porosity values with a root mean square error of 0.03. The four sedimentological environments showed significant differences in porosity, with mean porosity being lower for confluence and bar than for delta and secondary channel. Semi‐variogram analysis showed the absence of any spatial correlation in porosity for distances beyond 4 m. This shows that distance cannot be used as a parameter for porosity extrapolation in a fluvial system unless the extrapolation distance is less than 4 m. At least eight measurements of porosity are required to obtain a reliable estimate of mean porosity in a sedimentary environment, i.e. with uncertainty 〈0.03. Although grain size characteristics were found to have a significant impact on porosity, the relationships between these parameters and porosity were not very strong in this study. The unique porosity dataset, presented in this article, provides a valuable source of information for researchers and river managers.
    Description: Deutsche Forschungsgemeinschaft
    Keywords: ddc:550
    Language: English
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    Denudation Rate Changes Along a Fast‐Eroding Mountainous River With Slate Headwaters in Taiwan From 10Be (Meteoric)/9Be Ratios (2020)
    Details
    Publication Date: 2022-04-05
    Description: Abstract The novel 10Be (meteoric)/9Be system, where 10Be is delivered by precipitation and stable 9Be is released by weathering, provides denudation rates over weathering‐erosion timescales. The new tool is applicable to quartz‐poor lithologies, for example, mafic rock and claystone, which are not readily accessible by the commonly used in situ‐produced 10Be in quartz. We provide a first application of this proxy to a tectonically active mountainous river, the Zhuoshui River in Taiwan. Taiwan Rivers supply a disproportionately high suspended and dissolved flux to the oceans and are often underlain by fine‐grained shale/slate. 10Be (meteoric)/9Be‐derived denudation rates (Dmet) from the Zhuoshui Catchment are highest in the slate‐dominated headwaters (4–8 mm/year), and much lower (1–2 mm/year) along the midlower reaches with mixed lithologies. At the basin‐wide scale, we find a poor correlation between Dmet and basin‐averaged channel steepness despite a small climatic gradient. Because large lithological heterogeneities exist in this basin, we invoke a lithological effect to explain this poor correlation. Relying on a revised stream power incision model that incorporates rock erodibility, the resulting lithology‐ and runoff‐adjusted ksn (kLrsn) can be reconciled with denudation rates with the highest erodibility predicted to prevail in the Miocene slate of low metamorphic grade and high fracture density. This model suggests that the lithological heterogeneity can alter the coupling between surface denudation and channel morphology. On a broader perspective, the successful application of the 10Be (meteoric)/9Be proxy shows its applicability as a tracer for erosion and sediment transport processes in fast‐eroding mountain belts underlain by slate lithologies.
    Description: Key Points 10Be (meteoric)/9Be ratios quantify fast denudation of slate regions in Taiwan Topographic metrics and denudation rates show different spatial patterns Lithologic variability alters coupling between denudation rates and ksn, based on a revised stream power model including rock erodibility
    Description: Freie Universität Berlin‐China Scholarship Council PhD Program
    Description: National Natural Science Foundation of China http://dx.doi.org/10.13039/501100001809
    Keywords: ddc:551.3
    Language: English
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    Removing Disturbing Matrix Constituents from Biota Extracts from Total Extraction and Silicone‐Based Passive Sampling (2021)
    Details
    Publication Date: 2022-04-05
    Description: Contaminant analysis in biota extracts can be hampered by matrix interferences caused by, for example, co‐extracted lipids that compromise the quality of the analytical data and require frequent maintenance of the analytical instruments. In the present study, using gas chromatography coupled to high resolution mass spectrometry (GC‐HRMS), we aimed to develop and validate a straightforward, robust, and reproducible cleanup method with acceptable recoveries for diverse compound classes with a wide range of physicochemical properties representative of pollutant screening in biota extracts. We compared Oasis PRiME HLB cartridges, Agilent Captiva EMR‐Lipid cartridges, and “Freeze‐Out” with salmon lipids spiked with 113 target chemicals. The EMR‐Lipid cartridges provided extracts with low matrix effects at reproducible recoveries of the multi‐class target analytes (93 ± 9% and 95 ± 7% for low and high lipid amounts, respectively). The EMR‐Lipid cartridges were further tested with spiked pork lipids submitted to total extraction or silicone‐based passive sampling. Reproducible recoveries were achieved and matrix residuals were largely removed as demonstrated gravimetrically for both types of extracts. Ion suppression of halogenated compounds was not as efficiently removed by the cleanup of total and silicone‐based extracts of pork lipids as for the salmon lipids. However, the samples with clean up provided better instrument robustness than those without cleanup. Hence, EMR‐Lipid cartridges were shown to be efficient as a cleanup method in multi‐class monitoring of biota samples and open up new possibilities as a suitable cleanup method for silicone extracts in biota passive sampling studies using GC‐HRMS analysis. Environ Toxicol Chem 2021;40:2693–2704. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
    Description: H2020 European Research Council http://dx.doi.org/10.13039/100010663
    Keywords: ddc:577.14
    Language: English
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    Long‐Term Nitrate Trajectories Vary by Season in Western European Catchments (2021)
    Details
    Publication Date: 2022-04-05
    Description: Human alteration of nutrient cycles has caused persistent and widespread degradation of water quality around the globe. In many regions, including Western Europe, elevated nitrate (NO3−) concentration in surface waters contributes to eutrophication and noncompliance with environmental legislation. Discharge, NO3− concentrations and the vulnerability of the aquatic ecosystems to eutrophication often exhibit a distinct seasonality. Understanding spatial patterns and long‐term trends in this seasonality is crucial to improve water quality management. Here, we hypothesized that NO3− concentrations during high‐flow periods would respond faster to changes in nutrient inputs than low‐flow concentrations because of greater connectivity of shallow diffuse NO3− sources with the river network. To test this hypothesis, we compiled long‐term NO3− and discharge time series from 290 Western European catchments. To characterize the long‐term trajectories of seasonal NO3− concentration, we propose a novel hysteresis approach comparing low‐ and high‐flow NO3− concentration in the context of multi‐decadal N input changes. We found synchronous winter maxima of NO3− and discharge in 84% of the study catchments. However, contrary to our hypothesis, there were surprisingly diverse long‐term trajectories of seasonal NO3− concentration. Both clockwise (faster high‐flow NO3− response) and counterclockwise hysteresis (faster low‐flow NO3− response) occurred in similar proportions, potentially due to a high complexity in the underlying processes. Spatial variability of seasonality in NO3− concentration across the catchments was more pronounced and better predictable than its long‐term variability. This work demonstrates the value of seasonal and inter‐annual hydrochemical analysis and provides new tools for water quality monitoring and management.
    Description: Plain Language Summary: Nitrogen is an essential element of all living organisms and has thus often been used excessively as fertilizer to secure food production. However, surface waters can suffer from elevated nutrients inputs, causing toxic algal blooms and impairing drinking water quality, especially during summer low flows. To manage water quality, it is crucial to understand these seasonal variations of nitrogen and discharge and the underlying processes. We used data from 290 catchments in France and Germany to characterize average seasonality patterns and their long‐term evolution across the variety of landscapes and human influences. This allowed classifying catchment behavior and linking them to controls. As expected, both nitrogen and discharge peak during winter in most catchments (84%). However, there are well explainable deviations, for example, in mountainous regions. The long‐term evolution of seasonality was more diverse than expected suggesting a complex interplay of various processes with the long input history from fertilization and wastewater being part of the controls. We found that the differences among catchments were greater than the long‐term changes of seasonality within most catchments. By identifying catchment typologies, our study increases the understanding of nitrate seasonality patterns across a large extent and thus supports ecological water quality management.
    Description: Key Points: Spatial patterns of nitrate and discharge seasonality are linked to topography and hydroclimate with winter maxima dominating for both. After decreasing nutrient inputs, cases with decreases in river nitrate preceding during low‐ and high‐flow seasons occurred equally often. Spatial variability of nitrate seasonality is greater and more predictable from catchment characteristics than its long‐term variability.
    Description: Deutsche Forschungsgemeinschaft (DFG) http://dx.doi.org/10.13039/501100001659
    Description: Helmholtz Association http://dx.doi.org/10.13039/501100009318
    Description: US National Science Foundation (NSF)
    Keywords: ddc:551
    Language: English
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    Dissolved organic matter concentration, molecular composition, and functional groups in contrasting management practices of peatlands (2021)
    Details
    Publication Date: 2022-04-05
    Description: About 91,300 ha of peatlands has been rewetted in western Europe since the mid‐1990s. Still, it is unknown how long‐term rewetting alters the dissolved organic matter (DOM) concentration, molecular composition, and functional groups. We examined these DOM characteristics in three peatland types subjected to 47‐ to 231‐yr drainage and 18‐ to 24‐yr rewetting to address this knowledge gap. Cold water‐extractable DOM was characterized by pyrolysis field ionization mass spectrometry (Py‐FIMS) and X‐ray absorption near‐edge structure (XANES) spectroscopy. The dissolved organic carbon (DOC) concentration in the rewetted forest peatland was 2.7 times higher than in the drained forest peatland. However, rewetting decreased the DOC concentrations by 1.5 and 4 times in the coastal peatland and percolation mire, respectively, compared with their respective drained peatlands at the topsoil horizons. The Py‐FIMS analysis revealed that all nine DOM compound classes' relative abundances differed between the rewetted and drained forest peatland with the lower relative abundances of the labile DOM compound classes in the rewetted forest peatlands. However, most DOM compound classes' relative abundances were similar between the rewetted and drained coastal peatlands and percolation mires. The XANES also revealed nine carbon and seven nitrogen functional groups with no apparent differences between the two contrasting management practices. The influence of drainage and rewetting on DOC concentration and molecular composition depends on peatland type, drainage period, rewetting intensity, and peat degradation status that should be considered in future research for understanding DOM transformation and transportation from degraded and restored peatland ecosystems.
    Description: Core Ideas: Dissolved organic matter (DOM) concentrations and molecular compositions depend on degradation status in drained peatlands. Rewetting effects on DOM concentrations and molecular compositions differ with peatland types. Pyrolysis field ionization mass spectrometry reveals management effects on DOM molecular compositions compared with X‐ray absorption near‐edge structure.
    Keywords: ddc:577.687
    Language: English
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    High spatial‐resolution monitoring to investigate nitrate export and its drivers in a mesoscale river catchment along an anthropogenic land‐cover gradient (2021)
    John Wiley & Sons, Inc. | Hoboken, USA
    Details
    Publication Date: 2022-04-05
    Description: Nitrate monitoring is commonly conducted with low‐spatial resolution, only at the outlet or at a small number of selected locations. As a result, the information about spatial variations in nitrate export and its drivers is scarce. In this study, we present results of high‐spatial resolution monitoring conducted between 2012 and 2017 in 65 sub‐catchments in an Alpine mesoscale river catchment characterized by a land‐use gradient. We combined stable isotope techniques with Bayesian mixing models and geostatistical methods to investigate nitrate export and its main drivers, namely, microbial N turnover processes, land use and hydrological conditions. In the investigated sub‐catchments, mean values of NO3− concentrations and its isotope signatures (δ15NNO3 and δ18ONO3) varied from 2.6 to 26.7 mg L−1, from −1.3‰ to 13.1‰, and from −0.4‰ to 10.1‰, respectively. In this study, land use was an important driver for nitrate export. Very strong and strong positive correlations were found between percentages of agricultural land cover and δ15NNO3, and NO3− concentration, respectively. Mean proportional contributions of NO3− sources varied spatially and seasonally, and followed land‐use patterns. The mean contribution of manure and sewage was much higher in the catchments characterized by a high percentage of agricultural and urban land cover comparing to forested sub‐catchments. Specific NO3− loads were strongly correlated with specific discharge and moderately correlated with NO3− concentrations. The nitrate isotope and concentration analysis results suggest that nitrate from external sources is stored and accumulated in soil storage pools. Nitrification of reduced nitrogen species in those pools plays the most important role for the N‐dynamics in the Erlauf river catchment. Consequently, nitrification of reduced N sources was the main nitrate source except for a number of sub‐catchments dominated by agricultural land use. In the Erlauf catchment, denitrification plays only a minor role in controlling NO3− export on a regional scale.
    Description: We integrated results of the BMM with informative priors and top‐kriging. Reduced N stored in soil is an important source for stream N in a mesoscale catchment. Manure and sewage is the main NO3− source in agricultural sub‐catchments. Denitrification played only a minor role in controlling regional scale NO3− export.
    Keywords: ddc:551.48
    Language: English
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    Sources and Fate of the Antiandrogenic Fluorescent Dye 4‐Methyl‐7‐Diethylaminocoumarin in Small River Systems (2021)
    Details
    Publication Date: 2022-04-05
    Description: Recently, the potent antiandrogen 4‐methyl‐7‐diethylaminocoumarin (C47) and its potential transformation products 4‐methyl‐7‐ethylaminocoumarin (C47T1) and 4‐methyl‐7‐aminocoumarin (C47T2) were identified as novel environmental contaminants. We assessed for the first time the sources, distribution, and fate of these compounds in aquatic systems using the Holtemme River (Saxony‐Anhalt, Germany), which is a hotspot for these contaminants. To this end, wastewater‐treatment plant (WWTP) influent and effluent samples, surface water samples over 3 years, and the longitudinal profiles in water, sediment, and gammarids were analyzed. From the longitudinal profile of the river stretch, the WWTP of Silstedt was identified as the sole point source for these compounds in the River Holtemme, and exposure concentrations in the low micrograms per liter range could be recorded continuously over 3 years. Analysis of WWTP influent and effluent showed a transformation of approximately half of the C47 into C47T1 and C47T2 but no complete removal. A further attenuation of the three coumarins after discharge into the river could be largely attributed to dilution, while transformation was only approximately 20%, thus suggesting a significant persistence in aquatic systems. Experimentally derived partitioning coefficients between water and sediment organic carbon exceeded those predicted using the OPERA quantitative structure–activity relationship tools and polyparameter linear free‐energy relationships by up to 93‐fold, suggesting cation binding as a significant factor for their sorption behavior. Near‐equilibrium conditions between water and sediment were not observed close to the emitting WWTP but farther downstream in the river. Experimental and predicted bioaccumulation factors for gammarids were closely matching, and the concentrations in field‐sampled gammarids were close to steady state with exposure concentrations in the water phase of the river. Environ Toxicol Chem 2021;40:3078–3091. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.
    Description: Helmholtz‐Gemeinschaft http://dx.doi.org/10.13039/501100001656
    Description: Bundesministerium für Bildung und Forschung http://dx.doi.org/10.13039/501100002347
    Keywords: ddc:577.614
    Language: English
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    New estimates of ongoing sea level change and land movements caused by Glacial Isostatic Adjustment in the Mediterranean region (2022)
    Oxford University Press - The Royal Astronomical Society
    Details
    Publication Date: 2022-04-04
    Description: This article has been accepted for publication in Geophysical Journal International, ©:The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.
    Description: Glacial Isostatic Adjustment (GIA) caused by the melting of past ice sheets is still a major cause of sea level variations and 3-D crustal deformation in the Mediterranean region. However, since the contribution of GIA cannot be separated from those of oceanic or tectonic origin, its role can be only assessed by numerical modelling, solving the gravitationally self-consistent sea level equation. Nonetheless, uncertainties about the melting history of the late-Pleistocene ice sheets and the rheological profile of the Earth’s mantle affect the GIA predictions by an unknown amount. Estimating the GIA modelling uncertainties would be particularly important in the Mediterranean region, due to the amount of high quality geodetic data from space-borne and ground-based observations currently available, whose interpretation demands a suitable isostatic correction. Here we first review previous results about the effects of GIA in the Mediterranean Sea, enlightening the variability of all the fields affected by the persistent condition of isostatic disequilibrium. Then, for the first time in this region, we adopt an ensemble modelling approach to better constrain the present-day GIA contributions to sea level rise and geodetic variations, and their uncertainty.
    Description: Published
    Description: 984–998
    Description: 4A. Oceanografia e clima
    Description: JCR Journal
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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    Plastic and Us: looking at the marine litter problem from inside the rubbish. An unusual temporary exhibition at the Natural History Museum of the University of Pisa (2022)
    Details
    Publication Date: 2022-04-04
    Description: In this paper, we will describe a temporary exhibition held at the Museo di Storia Naturale dell’Università di Pisa (Natural History Museum of the University of Pisa, hereafter MSN), Italy, in year 2020-2021, and the educational and awareness raising results that the proposed approach has produced. The aim of this exhibition was to guide the visitor along a path of awareness on the very topical issue of “plastic in our environment”. It focused not only on the environmental impact produced by the dispersal of anthropogenic plastic waste, especially in the sea, but also on the awareness of what actions need to be taken, both on a govern-mental and personal level, by each of us, to limit it in the future. The exhibition started from the data and images proposed by the media, which shocked us with the seriousness of the plastic emergency and triggered worldwide attention. Then the emphasis of the exhibition shifted to scientific data, rigorously presented by researchers who study the issue directly in the field, in the Mediter-ranean Sea and along its coasts. Finally, the last exhibits addressed the issue of plastic disposal, inviting visitors to check their real knowledge about the concepts of degradable, compostable, or recyclable plastic, and to reflect on what could be the most effective means to limit plastic problems in the future. The plastic problem is exquisitely anthropogenic, and the exhibit was designed to make visitors feel involved. The mismanagement of the lifecycle of this material (from manufacturing processes to products’ end life) can be addressed on a global scale by drastically reducing the use and production of single-use plastic items, promoting proper waste management, and improving the effectiveness of recycling. The exhibition message was that laws are essential, as well as calling plastic producers to their responsibility, but something can also be done locally by us as individuals, through proper disposal and by producing less single-use plastic waste. Visitors’ attitudes and knowledge on this topic were investigated through online questionnaires prepared by experts in the field, and the data collected are presented and discussed in this paper.
    Description: Published
    Description: 338-356
    Description: 2TM. Divulgazione Scientifica
    Description: JCR Journal
    Keywords: Ocean Literacy ; marina litter ; environmental plastic impact ; museum exhibition ; virtual visit ; educational games
    Repository Name: Istituto Nazionale di Geofisica e Vulcanologia (INGV)
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