ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    Spatial and Temporal Distribution of Soil Microbial Properties in Two Shrub Intercrop Systems of the Sahel (2021)
    Frontiers Media
    Details
    Publication Date: 2021-03-12
    Description: The Sahel is an ecologically vulnerable region where increasing populations with a concurrent increase in agricultural intensity has degraded soils. Agroforestry offers an approach to remediate these landscapes. A largely unrecognized agroforestry resource in the Sahel are the native shrubs, Piliostigma reticulatum, and Guiera senegalensis that to varying degrees already coexist with row crops. These shrubs improve soil quality, redistribute water from the deep soil to the surface (hydraulic lift), and can improve crop growth. However, little information is available on whether these shrubs affect spatial and temporal dynamics of microbial communities. Therefore, the objective of this study was to determine microbial composition and activity in the wet and dry seasons of soil in the: shrub rhizosphere (RhizS), inter-root zone (IntrS), and outside the influence of shrub soil (OutS) for both G. senegalensis and P. reticulatum in Senegal. A 3 × 2 factorial field experiment was imposed at two locations (490 and 700 mm annual rainfall with G. senegalensis and P. reticulatum, respectively), that had the soil sampling treatments of three locations (RhizS, IntrS, and OutS) and two seasons (wet and dry). Soils were analyzed for: microbial diversity (DGGE with bacterial 16S or fungal 28S rRNA gene sequences phospholipids fatty acid, PLFA); enzyme activities; microbial biomass carbon (MBC); and nitrogen (N) mineralization potential. For the DGGE profiling, the bacterial community responded more to the rhizosphere effect, whereas, the fungal community was more sensitive to season. PLFA, MBC, enzyme activities and inorganic N were significantly higher in both seasons for the RhizS. The presence of shrubs maintained rhizosphere microbial communities and activity during the dry season. This represents a paradigm shift for semi-arid environments where logically it would be expected to have no microbial activity in the extended dry season. In contrast this study has shown this is not the case that rather the presence of shrub roots maintained the microbial community in the dry season most likely due to hydraulic lift and root exudates. This has implications when these shrubs are in cropped fields in that decomposition and mineralization of nutrients can proceed in the dry season. Thus, enabling accumulation of plant available nutrients during the dry season for uptake by crops in the rainy season.
    Electronic ISSN: 2571-581X
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Frontiers Media
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 2
    Electronic Resource
    Electronic Resource
    A fast moving easterly wave of the West Africa troposphere (1998)
    Springer
    Meteorology and atmospheric physics 69 (1998), S. 39-47 
    Details
    ISSN: 1436-5065
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Summary This paper documents a tropospheric synoptic-scale wavelike disturbance over Northern Africa and the tropical Atlantic during summer, in the 3.–5.day band period, different from the African wave. It has a velocity of 10–12 degree longitude per day instead of 6–8, a slighter shorter period, i.e. 3.5 instead of 4.5 days. It is best seen between 5°–7° N whilst the African wave has its largest amplitude about 12° N. The data used are NCEP/NCAR reanalyses and radiosonde data.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01025182
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Comparative influence of land and sea surfaces on the Sahelian drought: a numerical study (1996)
    Springer
    Annales geophysicae 14 (1996), S. 115-130 
    Details
    ISSN: 0992-7689
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract The aim of this work is to compare the relative impact of land and sea surface anomalies on Sahel rainfall and to describe the associated anomalies in the atmospheric general circulation. This sensitivity study was done with the Météo-France climate model: ARPEGE. The sensitivity to land surface conditions consists of changes in the management of water and heat exchanges by vegetation cover and bare soil. The sensitivity to ocean surfaces consists in forcing the lower boundary of the model with worldwide composite sea surface temperature (SST) anomalies obtained from the difference between 4 dry Sahel years and 4 wet Sahel years observed since 1970. For each case, the spatiotemporal variability of the simulated rainfall anomaly and changes in the modelled tropical easterly jet (TEJ) and African easterly jet (AEJ) are discussed. The global changes in land surface evaporation have caused a rainfall deficit over the Sahel and over the Guinea Coast. No significant changes in the simulated TEJ and an enhancement of the AEJ are found; at the surface, the energy budget and the hydrological cycle are substantially modified. On the other hand, SST anomalies induce a negative rainfall anomaly over the Sahel and a positive rainfall anomaly to the south of this area. The rainfall deficit due to those anomalies is consistent with previous diagnostic and sensitivity studies. The TEJ is weaker and the AEJ is stronger than in the reference. The composite impact of SST and land surfaces anomalies is also analyzed: the simulated rainfall anomaly is similar to the observed mean African drought patterns. This work suggests that large-scale variations of surface conditions may have a substantial influence on Sahel rainfall and shows the importance of land surface parameterization in climate change modelling. In addition, it points out the interest in accurately considering the land and sea surfaces conditions in sensitivity studies on Sahel rainfall.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s00585-996-0115-6
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Easterly wave regimes and associated convection over West Africa and tropical Atlantic: results from the NCEP/NCAR and ECMWF reanalyses (1999)
    Springer
    Climate dynamics 15 (1999), S. 795-822 
    Details
    ISSN: 1432-0894
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences , Physics
    Notes: Abstract  NCEP/NCAR and ECMWF daily reanalyses are used to investigate the synoptic variability of easterly waves over West Africa and tropical Atlantic at 700 hPa in northern summer between 1979–1995 (1979–1993 for ECMWF). Spectral analysis of the meridional wind component at 700 hPa highlighted two main periodicity bands, between 3 and 5 days, and 6 and 9 days. The 3–5-day easterly wave regime has already been widely investigated, but only on shorter datasets. These waves grow both north and south of the African Easterly Jet (AEJ). The two main tracks, noted over West Africa at 5 °N and 15 °N, converge over the Atlantic on latitude 17.5 °N. These waves are more active in August–September than in June–July. Their average wavelength/phase speed varies from about 3000 km/8 m s-1 north of the jet to 5000 km/12 m s-1 south of the jet. Rainfall, convection and monsoon flux are significantly modulated by these waves, convection in the Inter-Tropical Convergence Zone (ITCZ) being enhanced in the trough and ahead of it, with a wide meridional extension. Compared to the 3–5-day waves, the 6–9-day regime is intermittent and the corresponding wind field pattern has both similar and contrasting characteristics. The only main track is located north of the AEJ along 17.5 °N both over West Africa and the Atlantic. The mean wavelength is higher, about 5000 km long, and the average phase speed is about 7 m s-1. Then the wind field perturbation is mostly evident at the AEJ latitude and north of it. The perturbation structure is similar to that of 3–5-days in the north except that the more developed circulation centers, moving more to the north, lead to a large modulation of the jet zonal wind component. South of the AEJ, the wind field perturbation is weaker and quite different. The zonal wind core of the jet appears to be an almost symmetric axis in the 6–9-day wind field pattern, a clockwise circulation north of the AEJ being associated with a counter-clockwise circulation south of the jet, and vice versa. These 6–9-day easterly waves also affect significantly rainfall, convection and monsoon flux but in a different way, inducing large zonal convective bands in the ITCZ, mostly in the trough and behind it. As opposed to the 3–5-day wave regime, these rainfall anomalies are associated with anomalies of opposite sign over the Guinea coast and the Sahelian regions. Over the continent, these waves are more active in June–July, and in August–September over the ocean. GATE phase I gave an example of such an active 6–9-day wave pattern. Considered as a sequence of weak easterly wave activity, this phase was also a sequence of high 6–9-day easterly wave activity. We suggest that the 6–9-day regime results from an interaction between the 3–5-day easterly wave regime (maintained by the barotropic/baroclinic instability of the AEJ), and the development of strong anticyclonic circulations, north of the jet over West Africa, and both north and south of the jet over the Atlantic, significantly affecting the jet zonal wind component. The permanent subtropical anticyclones (Azores, Libya, St Helena) could help initiation and maintenance of such regime over West Africa and tropical Atlantic. Based on an a priori period-band criterion, our synoptic classification has enabled us to point out two statistical and meteorological easterly wave regimes over West Africa and tropical Atlantic. NCEP/NCAR and ECMWF reanalyses are in good agreement, the main difference being a more developed easterly wave activity in the NCEP/NCAR reanalyses, especially for the 3–5-day regime over the Atlantic.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s003820050316
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    facet.materialart.
    Unknown
    Genetic diversity of Jatropha curcas L. in Senegal compared with exotic accessions based on microsatellite markers (2014)
    Springer
    Details
    Publication Date: 2014-04-09
    Print ISSN: 0925-9864
    Electronic ISSN: 1573-5109
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 6
    facet.materialart.
    Unknown
    FUNGAL SYMBIONTS. Global assessment of arbuscular mycorrhizal fungus diversity reveals very low endemism (2015)
    American Association for the Advancement of Science (AAAS)
    Details
    Publication Date: 2015-09-01
    Description: The global biogeography of microorganisms remains largely unknown, in contrast to the well-studied diversity patterns of macroorganisms. We used arbuscular mycorrhizal (AM) fungus DNA from 1014 plant-root samples collected worldwide to determine the global distribution of these plant symbionts. We found that AM fungal communities reflected local environmental conditions and the spatial distance between sites. However, despite AM fungi apparently possessing limited dispersal ability, we found 93% of taxa on multiple continents and 34% on all six continents surveyed. This contrasts with the high spatial turnover of other fungal taxa and with the endemism displayed by plants at the global scale. We suggest that the biogeography of AM fungi is driven by unexpectedly efficient dispersal, probably via both abiotic and biotic vectors, including humans.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Davison, J -- Moora, M -- Opik, M -- Adholeya, A -- Ainsaar, L -- Ba, A -- Burla, S -- Diedhiou, A G -- Hiiesalu, I -- Jairus, T -- Johnson, N C -- Kane, A -- Koorem, K -- Kochar, M -- Ndiaye, C -- Partel, M -- Reier, U -- Saks, U -- Singh, R -- Vasar, M -- Zobel, M -- New York, N.Y. -- Science. 2015 Aug 28;349(6251):970-3. doi: 10.1126/science.aab1161.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Institute of Ecology and Earth Sciences, University of Tartu, Lai 40, Tartu 51005, Estonia. ; Centre for Mycorrhizal Research, The Energy and Resources Institute (TERI), India Habitat Centre, Lodhi Road, New Delhi 110 003, India. ; Laboratoire des Symbioses Tropicales et Mediterraneennes, Unite Mixte de Recherche 113, Laboratoire de Biologie et Physiologie Vegetales, Faculte des Sciences Exactes et Naturelles, Universite des Antilles, BP 592, 97159, Pointe-a-Pitre, Guadeloupe (French West Indies). ; Laboratoire Commun de Microbiologie de l'Institut de Recherche pour le Developpement-Institut Senegalais de Recherches Agricoles-Universite Cheikh Anta Diop (UCAD), Departement de Biologie Vegetale, UCAD, BP 5005 Dakar, Senegal. ; Institute of Ecology and Earth Sciences, University of Tartu, Lai 40, Tartu 51005, Estonia. Institute of Botany, Czech Academy of Sciences, Dukelska 135, 379 01 Trebon, Czech Republic. ; School of Earth Sciences and Environmental Sustainability, Northern Arizona University, Flagstaff, AZ 86011-5694, USA. ; Institute of Ecology and Earth Sciences, University of Tartu, Lai 40, Tartu 51005, Estonia. Netherlands Institute of Ecology, Droevendaalsesteeg 10, 6708 PB Wageningen, Netherlands. ; TERI-Deakin Nano Biotechnology Centre, Biotechnology and Management of Bioresources Division, TERI, India Habitat Centre, Lodhi Road, New Delhi 110 003, India.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26315436" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Biodiversity ; DNA, Fungal/analysis ; *Ecosystem ; Environment ; Humans ; *Mycorrhizae/genetics/isolation & purification/physiology ; Phylogeny ; Phylogeography ; Plant Roots/*microbiology ; *Symbiosis ; Water ; Wind
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 7
    facet.materialart.
    Unknown
    Management of ectomycorrhizal symbionts associated to useful exotic tree species to improve reforestation performances in tropical Africa (2010)
    Springer
    Details
    Publication Date: 2010-01-01
    Print ISSN: 1286-4560
    Electronic ISSN: 1297-966X
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 8
    facet.materialart.
    Unknown
    Mean kinematic characteristics of synoptic easterly disturbances over the Atlantic (2010)
    Springer
    Details
    Publication Date: 2010-04-21
    Print ISSN: 0256-1530
    Electronic ISSN: 1861-9533
    Topics: Geosciences , Physics
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 9
    facet.materialart.
    Unknown
    The human imperative of stabilizing global climate change at 1.5{degrees}C (2019)
    American Association for the Advancement of Science (AAAS)
    In: Science
    Details
    Publication Date: 2019
    Description: 〈p〉Increased concentrations of atmospheric greenhouse gases have led to a global mean surface temperature 1.0°C higher than during the pre-industrial period. We expand on the recent IPCC Special Report on global warming of 1.5°C and review the additional risks associated with higher levels of warming, each having major implications for multiple geographies, climates, and ecosystems. Limiting warming to 1.5°C rather than 2.0°C would be required to maintain substantial proportions of ecosystems and would have clear benefits for human health and economies. These conclusions are relevant for people everywhere, particularly in low- and middle-income countries, where the escalation of climate-related risks may prevent the achievement of the United Nations Sustainable Development Goals.〈/p〉
    Print ISSN: 0036-8075
    Electronic ISSN: 1095-9203
    Topics: Biology , Chemistry and Pharmacology , Computer Science , Medicine , Natural Sciences in General , Physics
    Published by American Association for the Advancement of Science (AAAS)
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
  • 10
    facet.materialart.
    Unknown
    Pairwise Transcriptomic Analysis of the Interactions Between the Ectomycorrhizal Fungus Laccaria bicolor S238N and Three Beneficial, Neutral and Antagonistic Soil Bacteria (2014)
    Springer
    Details
    Publication Date: 2014-08-02
    Print ISSN: 0095-3628
    Electronic ISSN: 1432-184X
    Topics: Biology
    Published by Springer
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    PAPER CURRENT
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...