ALBERT

Description: 25.08.-01.09.2019

Description: 02.09. bis 06.09.2019

Description: Umweltsensoren von GEOMAR und HZG wurden offenbar gewaltsam entfernt. 03.09.2019/Kiel. Im Dezember 2016 installierten das GEOMAR Helmholtz-Zentrum für Ozeanforschung Kiel und das Helmholtz-Zentrum Geesthacht in einem Sperrgebiet am Ausgang der Eckernförder Bucht ein Observatorium für Umweltmessungen am Meeresboden. Offenbar wurden die zwei, je 550 und 220 Kilogramm schweren Gestelle am 21. August mit großer Kraft von ihrer Position entfernt. Die Forscher fanden nur noch das zerfaserte Landanschlusskabel. Jetzt hoffen GEOMAR und HZG auf Hinweise, um die wertvollen Geräte zurückzuerhalten.

Description: 02.09.-08.09.2019

Description: M159 (29.10. – 20.11.2019) 2. Wochenbericht vom 10. November 2019

Description: This review article aims to provide an overview and insight into the most relevant aspects of wind energy development and current state-of-the-art. The industry is in a very mature stage, so it seems to be the right time to take stock of the relevant areas of wind energy use for power generation. For this review, the authors considered the essential aspects of the development of wind energy technology: research, modeling, and prediction of wind speed as an energy source, the technology development of the plants divided into the mechanical and electrical systems and the plant control, and finally the optimal plant operation including the maintenance strategies. The focus is on the development in Europe, with a partial focus on Germany. The authors are employees of the Fraunhofer Institutes, Institute for Energy Economics and Energy Systems Technology and Institute for Wind Energy Systems, who have contributed to the development of this technology for decades.

Description: (21th-25th October 2019)

Description: M159 (29.10. – 20.11.2019) 3. Wochenbericht vom 17. November 2019

Description: M159 (29.10. – 20.11.2019) 1. Wochenbericht vom 3. November 2019

Description: 02.12.19 - 08.12.19

Description: Dates of Cruise: 16.04. – 29.04.2018 Areas of Research: Physical, chemical, biological and fishery oceanography Port Calls: Visby, Sweden, 21. - 22.04.2018

Description: Dates of Cruise: 15.05. – 30.05.2018 Areas of Research: Physical, chemical, biological and fishery oceanography Port Calls: Riga. Latvia, 22.05.2018

Description: DIPLANOAGAP (Distribution of plastics in the North Atlantic garbage patch), 17.08.-24.08.2019

Description: 18.-30.9.2019 The overall objective of this practical for students is to investigate the ecological role of gelatinous plankton in the Baltic Sea food webs and alongside the salinity gradient. To demonstrate the temporal as well as spatial variation of pelagic communities such as bacteria-, phyto and zooplankton as well as in the benthic food webs, different food web tracers will be used. Main focus here is therefore to obtain qualitative and quantitative sample sets of gelatinous zooplankton to investigate their distinct role on bentho-pelagic processes. Over the last several decades, a significant increase of both frequency and severity of jellyfish (JF) blooms were reported worldwide. Blooms of these organisms can extend for thousands of square kilometers, with drastic consequences and economic losses. When JF outbreak, they will not only affect the pelagic community by direct feeding on fish larvae, fish eggs or competing for the prey with bigger fishes, but only serve as organic matter source for benthic systems via sinking to the sea floor. Due to the scarcity of data on the potential role of gelatinous zooplankton from only few locations in the Baltic Sea, there is only a limited understanding on the role of JF in the bentho-pelagic food web of the Baltic Sea. A quantitative and qualitative assessment of gelatinous zooplankton in the BS systems and their functioning with regard to salinity gradient of the Baltic Sea , are now urgently needed to better account for the role of gelatinous zooplankton in the future of the system. Applicant and working group have performed this student research/educational cruise with the specific focus on jellyfish ecology every year and on a regular basis since 2013. During this two-week cruise students will perform the compulsory „Practical at Sea“. The general goal is to survey and characterize the temporal and special distribution of bacterial, phyto-, zooplankton and macroplankton specially jellyfish in Skagerrak and Baltic Sea

Description: Poseidon 533 – AIMAC (Atmosphere–ocean–island-biogeochemical interactions in the Macaronesian Archipelagos) investigated the influence of the Cape Verdes, the Canary Islands, and Madeira on the physics, chemistry and biology of the surrounding subtropical North- East Atlantic ocean. The air – sea exchange of halocarbons from marine sources impact tropospheric and stratospheric chemistry, and therewith air quality and human health. High oceanic and atmospheric concentrations of iodinated, brominated and chlorinated methanes are often found near coastlines. In particular, bromoform (CHBr3) was recently detected at unexpectedly high concentrations in seawater of subtropical coasts, e.g. at Miami and Tenerife beaches. Bromoform is produced naturally from macro algae and phytoplankton and is the major marine vector of organic bromine to the atmosphere. Together with dibromomethane (CH2Br2), it is the main contributor to natural stratospheric bromine, involved in ozone depletion. Bromoform is also a major product during disinfection of seawater for many industrial and recreational purposes and during desalination processes. While the bromoform production from phytoplankton generally leads to picomolar concentrations in seawater, macroalgal production yields nanomolar concentrations and disinfection processes involving seawater can increase concentrations to micromolar levels. The latter has led to the occasional application of this compound as tracer for the effluents of power plants and wastewater discharges. Other disinfection by-products (DBP) in the effluents can lead to unfavorable effects on the environment and human health. As bromoform shows large concentrations in urbanized and industrialized regions, the elevated concentrations at many coasts may have a major and increasing contribution to the global budget.. We hypothesize, that populated coastlines show elevated bromoform concentrations from disinfection activities, related to the amount of population and industrial activities. Coastal alongshore currents may additionally trap the compound inshore. Therefore, bromoform can be a good tracer of the terrestrial and anthropogenic signal in the island mass effect, which describes the increase in nutrients and biological productivity in the surrounding water masses of an island. POS533 investigated the bromoform distribution in ocean and atmosphere in the subtropical East Atlantic and the islands of Madeira, Tenerife, Gran Canaria and the Cape Verde Archipelago, considering physical and biogeochemical parameters, phytoplankton distribution and carbon chemistry. During the cruise new scientific tools where applied, to differentiate between the islands natural and anthropogenic interactions with ocean and atmosphere. The measurements deliver the first comprehensive biogeochemical data set of phytoplankton, microbiology, trace gases, carbon, oxygen and nutrient cycling from this region close the islands in exchange with the open ocean. Despite the novel knowledge, current climate chemistry and chemical transport models used to understand the anthropogenic signal of marine halocarbon emissions and their effects on tropospheric oxidation and stratospheric ozone will benefit from the expedition's dataset.

Description: 09.12.19 - 16.12.19

Description: 18/2/2019-24/2/2019

Description: R.V. Poseidon cruise no. 522 Dates, Ports: 10.04.2018 (Catania, Italy) – 29.04.2018 (Malaga, Spain) Research subject: Tephrostratigraphy of tsunami-related deposits at Stromboli Chief Scientist: Dr. Armin Freundt, GEOMAR, Kiel Number of Scientists: 11 Project: Stromboli tsunamis

Description: 09.09. bis 12.09.2019

Description: In early 2017 we deployed eight KOSMOS [a] mesocosm units (53 m^3 each) close to ‘Isla San Lorenzo’ about 4.5 nm off-shore the Peruvian coastline (-12.0554667°, -077.2347667°). The aim of the study was to improve our mechanistic understanding of processes controlling plankton productivity, organic matter export, and particle stoichiometry in the coastal upwelling system off Peru. About 40 days into the study, Inca terns (Larosterna inca) – an abundant sea bird species in the region – discovered the mesocosms as suitable resting places. The birds were able to start and land on the very small areas lacking anti-bird spikes that were installed on the mesocosm roofs. Resting on the flotation frames as well as the opening of the mesocosm bags, they defecated into the enclosed water columns, adding new nutrients to the system. This orni-eutrophication from day 40 to 50 triggered intense phytoplankton blooms in the uppermost part of the enclosures where light was plentiful. This video illustrates the fertilizing effect of Inca tern defecation on phytoplankton communities during our mesocosm study in the upwelling system off Peru. [a] Kiel Off-Shore Mesocosms for Ocean Simulations

Description: 23.09. - 27.09.2019

Description: The reformed Common Fisheries Policy of the EU, in force since 2014, stipulates that overfishing by the fleets of its member states has to end latest in the year 2020. This study examines exploitation and status of 119 stocks fished by 20 countries in the Northeast Atlantic. In the year 2018, about 40% of the stocks were still subject to overfishing (F 〉 Fmsy), about 34% of the stocks were outside safe biological limits (B 〈 Bpa) and about 68% of the stocks were too depleted to produce maximum sustainable yields (B 〈 Bmsy). Reduction in the number of overfished stocks has stalled, possible because of an agreement between the European Commission (EC) and the International Council for the Exploration of the Seas (ICES), its advisory body for total allowed catches (TACs), wherein the EC requests ICES to give TAC advice leading to overfishing for many stocks. As a result, it is unlikely that overfishing will end in the Northeast Atlantic in 2020.

Description: Abstract Legal requirement in Europe asks for Ecosystem-Based Fisheries Management (EBFM) in European seas, including considerations of trophic interactions and minimization of negative impacts of fishing on food webs and ecosystem functioning. Focusing on the interaction between fisheries and ecosystem components, the trophic model presented here shows for the first time the “big picture” of the western Baltic Sea (WBS) food web by quantifying structure and flows between all trophic elements and the impact of fisheries that were and are active in the area, based on best available recent data. Model results show that fishing pressures exerted on the WBS since the early nineties of the past century forces not only top predators such as harbour porpoises and seals but also cod and other demersal fish to heavily compete for fish as food and to cover their dietary needs by shifting to organisms lower in the trophic web, mainly to benthic macrofauna and / or search for suitable prey in adjacent ecosystems such as Kattegat, Skagerrak, central Baltic Sea and North Sea. While common sense implementations of EBFM have been proposed, such as fishing all stocks below Fmsy and reducing fishing pressure even further for forage fish such as herring and sprat, few studies compared such fishing to alternative scenarios. Different options for EBFM, with regards to recovery of depleted stocks and sustainable future catches, are presented here based on the WBS ecosystem model, the legal framework given by the new Common Fisheries Policy (CFP) and the Marine Strategy Framework Directive (MSFD) of the European Union. The model explores four legally valid future fishery scenarios: 1) business as usual, 2) maximum sustainable fishing (F = Fmsy), 3) half of Fmsy, and 4) EBFM with F = 0.5 Fmsy for forage fish and F = 0.8 Fmsy for other fish. In addition, a “No-fishing” scenario demonstrates, that neither individual stocks nor the whole system would collapse when all fishing activities from 2017 on would cease. Simulations show that “Business as usual” would perpetuate low 2016 catches from depleted stocks in an unstable ecosystem where endangered species may be lost. In contrast, an “EBFM” scenario - with herring and sprat fished at 0.5 Fmsy level and cod and other stocks fished at 0.8 Fmsy level - allows the recovery of all stocks with strongly increased catches close to the maximum (at Fmsy) for cod and flatfish and catches similar to the 2016 level for herring and sprat but with strongly reduced fishing effort. Model and methodology presented here are considered suitable to assess MSFD Criterion D4C2 in the WBS.

Description: 4/2/2019 – 24/2/2019, Mindelo (Republic of Cape Verde) – Mindelo (Republic of Cape Verde) DeepC-Jelly We proposed to test the hypothesis that large gelatinous macrozooplankton (e.g. tunicates, hydrozoans) are a significant carbon storage in midwater, and a vector for carbon from midwater to the ocean floor in Cape Verde. To test this hypothesis, we studied 1) the distribution, diversity and abundance of gelatinous organisms in the epi-, meso-, and bathypelagic zone, 2) their role in transporting carbon through the pelagic foodweb to the seafloor and 3) their behavior and associations. We worked in the coastal deep sea off Santo Antão and Fogo as well as in the open ocean at the time series station CVOO and an eddy. A manned submersible was used for mesopelagic surveys, to document the behaviour and associations of deep-sea organisms and to collect living specimens. We performed pelagic video transects, discrete net sampling, and eDNA sampling down to 3000 m. ADCP and CTD transects allowed a detailed reconstruction of the effect of the islands on currents and productivity. To quantify the carbon flux of pelagic foodfalls, we also surveyed the seafloor. Sample and video analysis is still in progress, but first results indicate the impact of the pelagic tunicate Pyrosoma atlanticum, which is an upwelling-favored species largely absent from the oligotrophic open ocean, in the nearshore regions of Cape Verde as well as in the cyclonic eddy sampled. It was also observed on the seafloor and resembles a food source and a habitat in the water column and in the benthos. Specimens of pelagic fauna were collected that allow new species descriptions. New records and a new species for the region were also observed during benthic surveys. The cruise was documented in various outreach activities including national television in Cabo Verde.

Description: Plastid endosymbiosis has been a major force in the evolution of eukaryotic cellular complexity, but how endosymbionts are integrated is still poorly understood at a mechanistic level. Dinoflagellates, an ecologically important protist lineage, represent a unique model to study this process because dinoflagellate plastids have repeatedly been reduced, lost, and replaced by new plastids, leading to a spectrum of ages and integration levels. Here we describe deep-transcriptomic analyses of the Antarctic Ross Sea dinoflagellate (RSD), which harbors long-term but temporary kleptoplasts stolen from haptophyte prey, and is closely related to dinoflagellates with fully integrated plastids derived from different haptophytes. In some members of this lineage, called the Kareniaceae, their tertiary haptophyte plastids have crossed a tipping point to stable integration, but RSD has not, and may therefore reveal the order of events leading up to endosymbiotic integration. We show that RSD has retained its ancestral secondary plastid and has partitioned functions between this plastid and the kleptoplast. It has also obtained genes for kleptoplast-targeted proteins via horizontal gene transfer (HGT) that are not derived from the kleptoplast lineage. Importantly, many of these HGTs are also found in the related species with fully integrated plastids, which provides direct evidence that genetic integration preceded organelle fixation. Finally, we find that expression of kleptoplast-targeted genes is unaffected by environmental parameters, unlike prey-encoded homologs, suggesting that kleptoplast-targeted HGTs have adapted to posttranscriptional regulation mechanisms of the host.

Description: Significance: Although viruses are well-characterized regulators of eukaryotic algae, little is known about those infecting unicellular predators in oceans. We report the largest marine virus genome yet discovered, found in a wild predatory choanoflagellate sorted away from other Pacific microbes and pursued using integration of cultivation-independent and laboratory methods. The giant virus encodes nearly 900 proteins, many unlike known proteins, others related to cellular metabolism and organic matter degradation, and 3 type-1 rhodopsins. The viral rhodopsin that is most abundant in ocean metagenomes, and also present in an algal virus, pumps protons when illuminated, akin to cellular rhodopsins that generate a proton-motive force. Giant viruses likely provision multiple host species with photoheterotrophic capacities, including predatory unicellular relatives of animals. Abstract: Giant viruses are remarkable for their large genomes, often rivaling those of small bacteria, and for having genes thought exclusive to cellular life. Most isolated to date infect nonmarine protists, leaving their strategies and prevalence in marine environments largely unknown. Using eukaryotic single-cell metagenomics in the Pacific, we discovered a Mimiviridae lineage of giant viruses, which infects choanoflagellates, widespread protistan predators related to metazoans. The ChoanoVirus genomes are the largest yet from pelagic ecosystems, with 442 of 862 predicted proteins lacking known homologs. They are enriched in enzymes for modifying organic compounds, including degradation of chitin, an abundant polysaccharide in oceans, and they encode 3 divergent type-1 rhodopsins (VirR) with distinct evolutionary histories from those that capture sunlight in cellular organisms. One (VirRDTS) is similar to the only other putative rhodopsin from a virus (PgV) with a known host (a marine alga). Unlike the algal virus, ChoanoViruses encode the entire pigment biosynthesis pathway and cleavage enzyme for producing the required chromophore, retinal. We demonstrate that the rhodopsin shared by ChoanoViruses and PgV binds retinal and pumps protons. Moreover, our 1.65-Å resolved VirRDTS crystal structure and mutational analyses exposed differences from previously characterized type-1 rhodopsins, all of which come from cellular organisms. Multiple VirR types are present in metagenomes from across surface oceans, where they are correlated with and nearly as abundant as a canonical marker gene from Mimiviridae. Our findings indicate that light-dependent energy transfer systems are likely common components of giant viruses of photosynthetic and phagotrophic unicellular marine eukaryotes.

Description: Benthic foraminifera populate a diverse range of marine habitats. Their ability to use alternative electron acceptors—nitrate (NO3−) or oxygen (O2)—makes them important mediators of benthic nitrogen cycling. Nevertheless, the metabolic scaling of the two alternative respiration pathways and the environmental determinants of foraminiferal denitrification rates are yet unknown. We measured denitrification and O2 respiration rates for 10 benthic foraminifer species sampled in the Peruvian oxygen minimum zone (OMZ). Denitrification and O2 respiration rates significantly scale sublinearly with the cell volume. The scaling is lower for O2 respiration than for denitrification, indicating that NO3− metabolism during denitrification is more efficient than O2 metabolism during aerobic respiration in foraminifera from the Peruvian OMZ. The negative correlation of the O2 respiration rate with the surface/volume ratio is steeper than for the denitrification rate. This is likely explained by the presence of an intracellular NO3− storage in denitrifying foraminifera. Furthermore, we observe an increasing mean cell volume of the Peruvian foraminifera, under higher NO3− availability. This suggests that the cell size of denitrifying foraminifera is not limited by O2 but rather by NO3− availability. Based on our findings, we develop a mathematical formulation of foraminiferal cell volume as a predictor of respiration and denitrification rates, which can further constrain foraminiferal biogeochemical cycling in biogeochemical models. Our findings show that NO3− is the preferred electron acceptor in foraminifera from the OMZ, where the foraminiferal contribution to denitrification is governed by the ratio between NO3− and O2.

Description: Significance During the Holocene (11,600 y ago to present), northern peatlands accumulated significant C stocks over millennia. However, virtually nothing is known about peatlands that are no longer in the landscape, including ones formed prior to the Holocene: Where were they, when did they form, and why did they disappear? We used records of peatlands buried by mineral sediments for a reconstruction of peat-forming wetlands for the past 130,000 y. Northern peatlands expanded across high latitudes during warm periods and were buried during periods of glacial advance in northern latitudes. Thus, peat accumulation and burial represent a key long-term C storage mechanism in the Earth system. Abstract Glacial−interglacial variations in CO2 and methane in polar ice cores have been attributed, in part, to changes in global wetland extent, but the wetland distribution before the Last Glacial Maximum (LGM, 21 ka to 18 ka) remains virtually unknown. We present a study of global peatland extent and carbon (C) stocks through the last glacial cycle (130 ka to present) using a newly compiled database of 1,063 detailed stratigraphic records of peat deposits buried by mineral sediments, as well as a global peatland model. Quantitative agreement between modeling and observations shows extensive peat accumulation before the LGM in northern latitudes (〉40°N), particularly during warmer periods including the last interglacial (130 ka to 116 ka, MIS 5e) and the interstadial (57 ka to 29 ka, MIS 3). During cooling periods of glacial advance and permafrost formation, the burial of northern peatlands by glaciers and mineral sediments decreased active peatland extent, thickness, and modeled C stocks by 70 to 90% from warmer times. Tropical peatland extent and C stocks show little temporal variation throughout the study period. While the increased burial of northern peats was correlated with cooling periods, the burial of tropical peat was predominately driven by changes in sea level and regional hydrology. Peat burial by mineral sediments represents a mechanism for long-term terrestrial C storage in the Earth system. These results show that northern peatlands accumulate significant C stocks during warmer times, indicating their potential for C sequestration during the warming Anthropocene.

Description: “Praktikum auf See” is a cruise planned for master students of the biological oceanography at GEOMAR-Kiel. The main purpose of the expedition is to engage students in the real ocean science and exposing them to the “research-life on the sea”. We are going to sample for different fauna and flora of the central and easterly Baltic to be able to track biodiversity changes along the salinity gradient. This year’s cruise is combined with the sampling for the Horizon 2020 Project “GoJelly” in which samples for ecological studies of gelatinous zooplankton will be taken (www.gojelly.eu).

Description: F.K. Littorina Cruise No.: L19-04 Date of cruise: 06.05. - 10.05.2019 Areas of research: Public relations and Aquarium West Shore Port Calls: Grenå DK (07.05. - 08.05. & 08.05 – 09.05.2019)

Description: The RV Poseidon cruise 523 (POS523) is the second cruise to the work area as part of the observational program of the TRR 181 'Energy Transfers in Atmosphere and Ocean', and focussed on the energy transfer by low-mode internal waves. The goals of the cruise were to recover and redeploy a mooring to record the temporal variability of the internal wave field and associated energy fluxes, and to use time series CTD/LADCP/microstructure stations to assess locally the temporal variability of mixing, dissipation, and internal wave fluxes. The region south of the Azores in the east Atlantic is ideally suited for this kind of process study, because it is an area of a strong internal tide signal radiating away from the islands. The cruise track is located south of a chain of seamounts in a tidal beam formed by constructive interference of internal tides, and crosses the critical latitude for parametric subharmonic instability (PSI). During the cruise, we collected time series of CTD/LADCP and microstructure between 36 h and 52 h length on 5 stations in up to 4600 m water depth along the tidal beam between 29°20’N and 32°N latitude. In total 64 CTD/LADCP casts and 18 microstructure data sets were measured. The mooring equipped with current meter/temperature logger pairs and acoustic Doppler current profiler was successfully recovered and later redeployed along the track at 30°29’N, 30°12’W in a water depth of 4500 m (to be retrieved in 2019). All anticipated goals of the cruise were accomplished.

Description: 15.05 – 30.05.2019 The AL522 cruise extended a long-term data series on (eco-)system composition and functioning of the Baltic Sea, with a focus on the deeper basins. The series has been collected in similar form since 1986. A key characteristic of the cruise is the integration of oceanographic and biological information to enhance understanding of environmental and (fish) population fluctuations, and evolutionary processes in this system. The resulting data- and sample sets support ongoing projects in the Research Unit Marine Evolutionary Ecology at GEOMAR, as well as the EU Horizon 2020 project GoJelly and several international collaborations. The spatial focus lay on the Bornholm Basin as most important spawning area of Baltic cod, but also included the Western Baltic Sea, Arkona and Gotland Basin, Gdansk Deep, and Stolpe Trench. Specific investigations included a detailed hydrological survey (oxygen, salinity, temperature) of the cruise area, plankton surveys (zoo- and ichthyplankton including gelatinous plankton, with the goal to determine the composition and the abundance and vertical and horizontal distribution of species, and to take samples for later measurements of nutritional condition), and pelagic fishery hauls. The latter served to determine stock structure, gonadal maturation, stomach contents, and egg production of sprat and cod, and to sample tissue and otolith samples for individual-level genetic and ecological analyses of cod. The abundance and distribution of fishes in the cruise area was also assessed with hydroacoustic methods. Additional cruise components were: (i) cod gonad and liver sampling for fecundity + parasite studies, (ii) vertically resolved plankton sampling for studies of plankton phenology (iii) depth-resolved sampling of microplastic using an neuston sledge (iv) sampling and experimental work of photosynthesis rates of different phytoplankton fractions (v) eDNA filter sampling to compare with traditional net based methods.