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  • *Ecosystem  (14)
  • Nature Publishing Group (NPG)  (14)
  • American Physical Society
  • 2005-2009  (14)
  • 1980-1984
  • 1965-1969
  • 2008  (14)
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  • 2005-2009  (14)
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  • 1
    Publication Date: 2008-02-29
    Description: Many free-ranging predators have to make foraging decisions with little, if any, knowledge of present resource distribution and availability. The optimal search strategy they should use to maximize encounter rates with prey in heterogeneous natural environments remains a largely unresolved issue in ecology. Levy walks are specialized random walks giving rise to fractal movement trajectories that may represent an optimal solution for searching complex landscapes. However, the adaptive significance of this putative strategy in response to natural prey distributions remains untested. Here we analyse over a million movement displacements recorded from animal-attached electronic tags to show that diverse marine predators-sharks, bony fishes, sea turtles and penguins-exhibit Levy-walk-like behaviour close to a theoretical optimum. Prey density distributions also display Levy-like fractal patterns, suggesting response movements by predators to prey distributions. Simulations show that predators have higher encounter rates when adopting Levy-type foraging in natural-like prey fields compared with purely random landscapes. This is consistent with the hypothesis that observed search patterns are adapted to observed statistical patterns of the landscape. This may explain why Levy-like behaviour seems to be widespread among diverse organisms, from microbes to humans, as a 'rule' that evolved in response to patchy resource distributions.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Sims, David W -- Southall, Emily J -- Humphries, Nicolas E -- Hays, Graeme C -- Bradshaw, Corey J A -- Pitchford, Jonathan W -- James, Alex -- Ahmed, Mohammed Z -- Brierley, Andrew S -- Hindell, Mark A -- Morritt, David -- Musyl, Michael K -- Righton, David -- Shepard, Emily L C -- Wearmouth, Victoria J -- Wilson, Rory P -- Witt, Matthew J -- Metcalfe, Julian D -- England -- Nature. 2008 Feb 28;451(7182):1098-102. doi: 10.1038/nature06518.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Marine Biological Association of the United Kingdom, The Laboratory, Citadel Hill, Plymouth PL1 2PB, UK. dws@mba.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18305542" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; *Ecosystem ; Euphausiacea ; *Feeding Behavior ; Fractals ; Gadiformes ; *Marine Biology ; *Models, Biological ; *Motor Activity ; Oceans and Seas ; Population Density ; *Predatory Behavior ; Probability ; Seals, Earless ; Sharks ; Spheniscidae ; Tuna ; Turtles
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    Electronic ISSN: 1476-4687
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
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  • 2
    Publication Date: 2008-09-19
    Description: Terrestrial ecosystems control carbon dioxide fluxes to and from the atmosphere through photosynthesis and respiration, a balance between net primary productivity and heterotrophic respiration, that determines whether an ecosystem is sequestering carbon or releasing it to the atmosphere. Global and site-specific data sets have demonstrated that climate and climate variability influence biogeochemical processes that determine net ecosystem carbon dioxide exchange (NEE) at multiple timescales. Experimental data necessary to quantify impacts of a single climate variable, such as temperature anomalies, on NEE and carbon sequestration of ecosystems at interannual timescales have been lacking. This derives from an inability of field studies to avoid the confounding effects of natural intra-annual and interannual variability in temperature and precipitation. Here we present results from a four-year study using replicate 12,000-kg intact tallgrass prairie monoliths located in four 184-m(3) enclosed lysimeters. We exposed 6 of 12 monoliths to an anomalously warm year in the second year of the study and continuously quantified rates of ecosystem processes, including NEE. We find that warming decreases NEE in both the extreme year and the following year by inducing drought that suppresses net primary productivity in the extreme year and by stimulating heterotrophic respiration of soil biota in the subsequent year. Our data indicate that two years are required for NEE in the previously warmed experimental ecosystems to recover to levels measured in the control ecosystems. This time lag caused net ecosystem carbon sequestration in previously warmed ecosystems to be decreased threefold over the study period, compared with control ecosystems. Our findings suggest that more frequent anomalously warm years, a possible consequence of increasing anthropogenic carbon dioxide levels, may lead to a sustained decrease in carbon dioxide uptake by terrestrial ecosystems.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Arnone, John A 3rd -- Verburg, Paul S J -- Johnson, Dale W -- Larsen, Jessica D -- Jasoni, Richard L -- Lucchesi, Annmarie J -- Batts, Candace M -- von Nagy, Christopher -- Coulombe, William G -- Schorran, David E -- Buck, Paul E -- Braswell, Bobby H -- Coleman, James S -- Sherry, Rebecca A -- Wallace, Linda L -- Luo, Yiqi -- Schimel, David S -- England -- Nature. 2008 Sep 18;455(7211):383-6. doi: 10.1038/nature07296.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Desert Research Institute, Reno, Nevada 89512, USA. jarnone@dri.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18800137" target="_blank"〉PubMed〈/a〉
    Keywords: Carbon Dioxide/*metabolism ; *Climate ; Disasters ; *Ecosystem ; *Hot Temperature ; Time Factors
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  • 3
    Publication Date: 2008-01-04
    Description: The carbon balance of terrestrial ecosystems is particularly sensitive to climatic changes in autumn and spring, with spring and autumn temperatures over northern latitudes having risen by about 1.1 degrees C and 0.8 degrees C, respectively, over the past two decades. A simultaneous greening trend has also been observed, characterized by a longer growing season and greater photosynthetic activity. These observations have led to speculation that spring and autumn warming could enhance carbon sequestration and extend the period of net carbon uptake in the future. Here we analyse interannual variations in atmospheric carbon dioxide concentration data and ecosystem carbon dioxide fluxes. We find that atmospheric records from the past 20 years show a trend towards an earlier autumn-to-winter carbon dioxide build-up, suggesting a shorter net carbon uptake period. This trend cannot be explained by changes in atmospheric transport alone and, together with the ecosystem flux data, suggest increasing carbon losses in autumn. We use a process-based terrestrial biosphere model and satellite vegetation greenness index observations to investigate further the observed seasonal response of northern ecosystems to autumnal warming. We find that both photosynthesis and respiration increase during autumn warming, but the increase in respiration is greater. In contrast, warming increases photosynthesis more than respiration in spring. Our simulations and observations indicate that northern terrestrial ecosystems may currently lose carbon dioxide in response to autumn warming, with a sensitivity of about 0.2 PgC degrees C(-1), offsetting 90% of the increased carbon dioxide uptake during spring. If future autumn warming occurs at a faster rate than in spring, the ability of northern ecosystems to sequester carbon may be diminished earlier than previously suggested.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Piao, Shilong -- Ciais, Philippe -- Friedlingstein, Pierre -- Peylin, Philippe -- Reichstein, Markus -- Luyssaert, Sebastiaan -- Margolis, Hank -- Fang, Jingyun -- Barr, Alan -- Chen, Anping -- Grelle, Achim -- Hollinger, David Y -- Laurila, Tuomas -- Lindroth, Anders -- Richardson, Andrew D -- Vesala, Timo -- England -- Nature. 2008 Jan 3;451(7174):49-52. doi: 10.1038/nature06444.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉LSCE, UMR CEA-CNRS, Batiment 709, CE, L'Orme des Merisiers, F-91191 Gif-sur-Yvette, France. slpiao@lsce.ipsl.fr〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18172494" target="_blank"〉PubMed〈/a〉
    Keywords: Atmosphere/chemistry ; Biomass ; Carbon Dioxide/analysis/*metabolism ; Cell Respiration ; *Ecosystem ; Fossil Fuels ; Geography ; Greenhouse Effect ; History, 20th Century ; History, 21st Century ; Oceans and Seas ; Photosynthesis ; Plant Transpiration ; Plants/metabolism ; Rain ; *Seasons ; Soil/analysis ; *Temperature ; Water/metabolism
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  • 4
    Publication Date: 2008-09-12
    Description: Old-growth forests remove carbon dioxide from the atmosphere at rates that vary with climate and nitrogen deposition. The sequestered carbon dioxide is stored in live woody tissues and slowly decomposing organic matter in litter and soil. Old-growth forests therefore serve as a global carbon dioxide sink, but they are not protected by international treaties, because it is generally thought that ageing forests cease to accumulate carbon. Here we report a search of literature and databases for forest carbon-flux estimates. We find that in forests between 15 and 800 years of age, net ecosystem productivity (the net carbon balance of the forest including soils) is usually positive. Our results demonstrate that old-growth forests can continue to accumulate carbon, contrary to the long-standing view that they are carbon neutral. Over 30 per cent of the global forest area is unmanaged primary forest, and this area contains the remaining old-growth forests. Half of the primary forests (6 x 10(8) hectares) are located in the boreal and temperate regions of the Northern Hemisphere. On the basis of our analysis, these forests alone sequester about 1.3 +/- 0.5 gigatonnes of carbon per year. Thus, our findings suggest that 15 per cent of the global forest area, which is currently not considered when offsetting increasing atmospheric carbon dioxide concentrations, provides at least 10 per cent of the global net ecosystem productivity. Old-growth forests accumulate carbon for centuries and contain large quantities of it. We expect, however, that much of this carbon, even soil carbon, will move back to the atmosphere if these forests are disturbed.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Luyssaert, Sebastiaan -- Schulze, E-Detlef -- Borner, Annett -- Knohl, Alexander -- Hessenmoller, Dominik -- Law, Beverly E -- Ciais, Philippe -- Grace, John -- England -- Nature. 2008 Sep 11;455(7210):213-5. doi: 10.1038/nature07276.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biology, University of Antwerp, 2610 Wilrijk, Belgium. sebastiaan.luyssaert@ua.ac.be〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18784722" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Atmosphere/chemistry ; Biomass ; Carbon/*metabolism ; Carbon Dioxide/metabolism ; Databases, Factual ; Disasters ; *Ecosystem ; History, 15th Century ; History, 16th Century ; History, 17th Century ; History, 18th Century ; History, 19th Century ; History, 20th Century ; History, 21st Century ; History, Ancient ; History, Medieval ; Human Activities ; Time Factors ; Trees/*metabolism
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  • 5
    Publication Date: 2008-03-04
    Description: Viruses, and more particularly phages (viruses that infect bacteria), represent one of the most abundant living entities in aquatic and terrestrial environments. The biogeography of phages has only recently been investigated and so far reveals a cosmopolitan distribution of phage genetic material (or genotypes). Here we address this cosmopolitan distribution through the analysis of phage communities in modern microbialites, the living representatives of one of the most ancient life forms on Earth. On the basis of a comparative metagenomic analysis of viral communities associated with marine (Highborne Cay, Bahamas) and freshwater (Pozas Azules II and Rio Mesquites, Mexico) microbialites, we show that some phage genotypes are geographically restricted. The high percentage of unknown sequences recovered from the three metagenomes (〉97%), the low percentage similarities with sequences from other environmental viral (n = 42) and microbial (n = 36) metagenomes, and the absence of viral genotypes shared among microbialites indicate that viruses are genetically unique in these environments. Identifiable sequences in the Highborne Cay metagenome were dominated by single-stranded DNA microphages that were not detected in any other samples examined, including sea water, fresh water, sediment, terrestrial, extreme, metazoan-associated and marine microbial mats. Finally, a marine signature was present in the phage community of the Pozas Azules II microbialites, even though this environment has not been in contact with the ocean for tens of millions of years. Taken together, these results prove that viruses in modern microbialites display biogeographical variability and suggest that they may be derived from an ancient community.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Desnues, Christelle -- Rodriguez-Brito, Beltran -- Rayhawk, Steve -- Kelley, Scott -- Tran, Tuong -- Haynes, Matthew -- Liu, Hong -- Furlan, Mike -- Wegley, Linda -- Chau, Betty -- Ruan, Yijun -- Hall, Dana -- Angly, Florent E -- Edwards, Robert A -- Li, Linlin -- Thurber, Rebecca Vega -- Reid, R Pamela -- Siefert, Janet -- Souza, Valeria -- Valentine, David L -- Swan, Brandon K -- Breitbart, Mya -- Rohwer, Forest -- England -- Nature. 2008 Mar 20;452(7185):340-3. doi: 10.1038/nature06735. Epub 2008 Mar 2.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biology, San Diego State University, San Diego, California 92182, USA. cdesnues@yahoo.fr〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18311127" target="_blank"〉PubMed〈/a〉
    Keywords: Bacteriophages/classification/genetics/*isolation & purification/*physiology ; Bahamas ; *Biodiversity ; Capsid/chemistry ; Computational Biology ; DNA, Viral/analysis/genetics ; *Ecosystem ; Fresh Water/microbiology/virology ; Genome, Viral/genetics ; Genomics ; *Geography ; Geologic Sediments/microbiology/virology ; Mexico ; Molecular Sequence Data ; Phylogeny ; Proteome/metabolism ; Seawater/microbiology/virology ; *Water Microbiology
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  • 6
    Publication Date: 2008-03-14
    Description: Anthropogenic addition of bioavailable nitrogen to the biosphere is increasing and terrestrial ecosystems are becoming increasingly nitrogen-saturated, causing more bioavailable nitrogen to enter groundwater and surface waters. Large-scale nitrogen budgets show that an average of about 20-25 per cent of the nitrogen added to the biosphere is exported from rivers to the ocean or inland basins, indicating that substantial sinks for nitrogen must exist in the landscape. Streams and rivers may themselves be important sinks for bioavailable nitrogen owing to their hydrological connections with terrestrial systems, high rates of biological activity, and streambed sediment environments that favour microbial denitrification. Here we present data from nitrogen stable isotope tracer experiments across 72 streams and 8 regions representing several biomes. We show that total biotic uptake and denitrification of nitrate increase with stream nitrate concentration, but that the efficiency of biotic uptake and denitrification declines as concentration increases, reducing the proportion of in-stream nitrate that is removed from transport. Our data suggest that the total uptake of nitrate is related to ecosystem photosynthesis and that denitrification is related to ecosystem respiration. In addition, we use a stream network model to demonstrate that excess nitrate in streams elicits a disproportionate increase in the fraction of nitrate that is exported to receiving waters and reduces the relative role of small versus large streams as nitrate sinks.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mulholland, Patrick J -- Helton, Ashley M -- Poole, Geoffrey C -- Hall, Robert O -- Hamilton, Stephen K -- Peterson, Bruce J -- Tank, Jennifer L -- Ashkenas, Linda R -- Cooper, Lee W -- Dahm, Clifford N -- Dodds, Walter K -- Findlay, Stuart E G -- Gregory, Stanley V -- Grimm, Nancy B -- Johnson, Sherri L -- McDowell, William H -- Meyer, Judy L -- Valett, H Maurice -- Webster, Jackson R -- Arango, Clay P -- Beaulieu, Jake J -- Bernot, Melody J -- Burgin, Amy J -- Crenshaw, Chelsea L -- Johnson, Laura T -- Niederlehner, B R -- O'Brien, Jonathan M -- Potter, Jody D -- Sheibley, Richard W -- Sobota, Daniel J -- Thomas, Suzanne M -- England -- Nature. 2008 Mar 13;452(7184):202-5. doi: 10.1038/nature06686.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, USA. mulhollandpj@ornl.gov〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18337819" target="_blank"〉PubMed〈/a〉
    Keywords: Agriculture ; Bacteria/metabolism ; Computer Simulation ; *Ecosystem ; Geography ; *Human Activities ; Nitrates/*analysis/*metabolism ; Nitrites/*analysis/*metabolism ; Nitrogen/analysis/metabolism ; Nitrogen Isotopes ; Plants/metabolism ; Rivers/*chemistry ; Urbanization
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  • 7
    Publication Date: 2008-03-14
    Description: Microbial activities shape the biogeochemistry of the planet and macroorganism health. Determining the metabolic processes performed by microbes is important both for understanding and for manipulating ecosystems (for example, disruption of key processes that lead to disease, conservation of environmental services, and so on). Describing microbial function is hampered by the inability to culture most microbes and by high levels of genomic plasticity. Metagenomic approaches analyse microbial communities to determine the metabolic processes that are important for growth and survival in any given environment. Here we conduct a metagenomic comparison of almost 15 million sequences from 45 distinct microbiomes and, for the first time, 42 distinct viromes and show that there are strongly discriminatory metabolic profiles across environments. Most of the functional diversity was maintained in all of the communities, but the relative occurrence of metabolisms varied, and the differences between metagenomes predicted the biogeochemical conditions of each environment. The magnitude of the microbial metabolic capabilities encoded by the viromes was extensive, suggesting that they serve as a repository for storing and sharing genes among their microbial hosts and influence global evolutionary and metabolic processes.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dinsdale, Elizabeth A -- Edwards, Robert A -- Hall, Dana -- Angly, Florent -- Breitbart, Mya -- Brulc, Jennifer M -- Furlan, Mike -- Desnues, Christelle -- Haynes, Matthew -- Li, Linlin -- McDaniel, Lauren -- Moran, Mary Ann -- Nelson, Karen E -- Nilsson, Christina -- Olson, Robert -- Paul, John -- Brito, Beltran Rodriguez -- Ruan, Yijun -- Swan, Brandon K -- Stevens, Rick -- Valentine, David L -- Thurber, Rebecca Vega -- Wegley, Linda -- White, Bryan A -- Rohwer, Forest -- England -- Nature. 2008 Apr 3;452(7187):629-32. doi: 10.1038/nature06810. Epub 2008 Mar 12.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Biology, San Diego State University, San Diego, California 92182, USA. elizabeth_dinsdale@hotmail.com〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18337718" target="_blank"〉PubMed〈/a〉
    Keywords: Animals ; Anthozoa/physiology ; Archaea/genetics/isolation & purification/metabolism ; Bacteria/*genetics/isolation & purification/*metabolism ; Chemotaxis/genetics ; Computational Biology ; Culicidae/physiology ; *Ecosystem ; Fishes/physiology ; Fresh Water ; *Gene Expression Profiling ; Genome, Archaeal ; Genome, Bacterial ; Genome, Viral ; *Genomics ; Microbiology ; Seawater ; Viruses/*genetics/isolation & purification/*metabolism
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  • 8
    Publication Date: 2008-02-08
    Description: Rates of atmospheric deposition of biologically active nitrogen (N) are two to seven times the pre-industrial rates in many developed nations because of combustion of fossil fuels and agricultural fertilization. They are expected to increase similarly over the next 50 years in industrializing nations of Asia and South America. Although the environmental impacts of high rates of nitrogen addition have been well studied, this is not so for the lower, chronic rates that characterize much of the globe. Here we present results of the first multi-decadal experiment to examine the impacts of chronic, experimental nitrogen addition as low as 10 kg N ha(-1) yr(-1) above ambient atmospheric nitrogen deposition (6 kg N ha(-1) yr(-1) at our site). This total input rate is comparable to terrestrial nitrogen deposition in many industrialized nations. We found that this chronic low-level nitrogen addition rate reduced plant species numbers by 17% relative to controls receiving ambient N deposition. Moreover, species numbers were reduced more per unit of added nitrogen at lower addition rates, suggesting that chronic but low-level nitrogen deposition may have a greater impact on diversity than previously thought. A second experiment showed that a decade after cessation of nitrogen addition, relative plant species number, although not species abundances, had recovered, demonstrating that some effects of nitrogen addition are reversible.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Clark, Christopher M -- Tilman, David -- England -- Nature. 2008 Feb 7;451(7179):712-5. doi: 10.1038/nature06503.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Ecology, Evolution and Behavior, 100 Ecology, 1987 Upper Buford Circle, University of Minnesota, St. Paul, Minnesota 55108, USA. clark134@umn.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18256670" target="_blank"〉PubMed〈/a〉
    Keywords: *Biodiversity ; Biomass ; *Ecosystem ; Nitrogen/*metabolism ; Plants/classification/*metabolism ; *Poaceae/metabolism ; Random Allocation ; Time Factors
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  • 9
    Publication Date: 2008-05-10
    Description: The Amazon rainforest plays a crucial role in the climate system, helping to drive atmospheric circulations in the tropics by absorbing energy and recycling about half of the rainfall that falls on it. This region (Amazonia) is also estimated to contain about one-tenth of the total carbon stored in land ecosystems, and to account for one-tenth of global, net primary productivity. The resilience of the forest to the combined pressures of deforestation and global warming is therefore of great concern, especially as some general circulation models (GCMs) predict a severe drying of Amazonia in the twenty-first century. Here we analyse these climate projections with reference to the 2005 drought in western Amazonia, which was associated with unusually warm North Atlantic sea surface temperatures (SSTs). We show that reduction of dry-season (July-October) rainfall in western Amazonia correlates well with an index of the north-south SST gradient across the equatorial Atlantic (the 'Atlantic N-S gradient'). Our climate model is unusual among current GCMs in that it is able to reproduce this relationship and also the observed twentieth-century multidecadal variability in the Atlantic N-S gradient, provided that the effects of aerosols are included in the model. Simulations for the twenty-first century using the same model show a strong tendency for the SST conditions associated with the 2005 drought to become much more common, owing to continuing reductions in reflective aerosol pollution in the Northern Hemisphere.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Cox, Peter M -- Harris, Phil P -- Huntingford, Chris -- Betts, Richard A -- Collins, Matthew -- Jones, Chris D -- Jupp, Tim E -- Marengo, Jose A -- Nobre, Carlos A -- England -- Nature. 2008 May 8;453(7192):212-5. doi: 10.1038/nature06960.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉School of Engineering, Computing and Mathematics, University of Exeter, Exeter EX4 4QF, UK. p.m.cox@exeter.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18464740" target="_blank"〉PubMed〈/a〉
    Keywords: Aerosols/*analysis ; Atlantic Ocean ; Carbon Dioxide/analysis ; Disasters/history/*statistics & numerical data ; *Ecosystem ; Environmental Pollution/*statistics & numerical data ; *Greenhouse Effect ; History, 20th Century ; History, 21st Century ; *Models, Theoretical ; Pacific Ocean ; Probability ; Rain ; Seasons ; South America ; Temperature ; Trees/*physiology
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  • 10
    Publication Date: 2008-06-10
    Description: The atmospheric partial pressure of carbon dioxide (p(CO(2))) will almost certainly be double that of pre-industrial levels by 2100 and will be considerably higher than at any time during the past few million years. The oceans are a principal sink for anthropogenic CO(2) where it is estimated to have caused a 30% increase in the concentration of H(+) in ocean surface waters since the early 1900s and may lead to a drop in seawater pH of up to 0.5 units by 2100 (refs 2, 3). Our understanding of how increased ocean acidity may affect marine ecosystems is at present very limited as almost all studies have been in vitro, short-term, rapid perturbation experiments on isolated elements of the ecosystem. Here we show the effects of acidification on benthic ecosystems at shallow coastal sites where volcanic CO(2) vents lower the pH of the water column. Along gradients of normal pH (8.1-8.2) to lowered pH (mean 7.8-7.9, minimum 7.4-7.5), typical rocky shore communities with abundant calcareous organisms shifted to communities lacking scleractinian corals with significant reductions in sea urchin and coralline algal abundance. To our knowledge, this is the first ecosystem-scale validation of predictions that these important groups of organisms are susceptible to elevated amounts of p(CO(2)). Sea-grass production was highest in an area at mean pH 7.6 (1,827 (mu)atm p(CO(2))) where coralline algal biomass was significantly reduced and gastropod shells were dissolving due to periods of carbonate sub-saturation. The species populating the vent sites comprise a suite of organisms that are resilient to naturally high concentrations of p(CO(2)) and indicate that ocean acidification may benefit highly invasive non-native algal species. Our results provide the first in situ insights into how shallow water marine communities might change when susceptible organisms are removed owing to ocean acidification.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hall-Spencer, Jason M -- Rodolfo-Metalpa, Riccardo -- Martin, Sophie -- Ransome, Emma -- Fine, Maoz -- Turner, Suzanne M -- Rowley, Sonia J -- Tedesco, Dario -- Buia, Maria-Cristina -- England -- Nature. 2008 Jul 3;454(7200):96-9. doi: 10.1038/nature07051. Epub 2008 Jun 8.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Marine Institute, Marine Biology and Ecology Research Centre, University of Plymouth, Plymouth PL4 8AA, UK. jhall-spencer@plymouth.ac.uk〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18536730" target="_blank"〉PubMed〈/a〉
    Keywords: Acids/analysis/chemistry ; Alismatidae/physiology ; Animals ; Atlantic Ocean ; Calcium Carbonate/analysis ; *Carbon Dioxide/pharmacology ; *Ecosystem ; Eukaryota/physiology ; Hydrogen-Ion Concentration ; Invertebrates/physiology ; Italy ; Population Density ; Seawater/*chemistry ; *Volcanic Eruptions
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