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C J Stevens - One of the best experts on this subject based on the ideXlab platform.
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Nitrogen Deposition and Terrestrial Biodiversity
Encyclopedia of Biodiversity, 2013Co-Authors: Christopher M. Clark, C J Stevens, Yongfei Bai, William D. Bowman, Jane Cowles, Mark E. Fenn, Frank S. Gilliam, Gareth K. Phoenix, Ilyas Siddique, Harald SverdrupAbstract:Nitrogen Deposition, along with habitat loss and climate change, constitute a major threat to Earth’s biodiversity. Fossil fuel combustion and modern agriculture add more Nitrogen to terrestrial and aquatic ecosystems than all natural processes combined. Because Nitrogen often limits productivity, this enrichment it likely to have major ecological impacts. In terrestrial ecosystems, Nitrogen Deposition can lead to increased growth of often weedy species, cation depletion in the soil, nutrient imbalances in plant tissue, and soil acidification among other effects. These processes often reduce plant biodiversity and homogenize communities, which can propagate through food webs and impact entire ecosystems.
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Addressing the Impact of Atmospheric Nitrogen Deposition on Western European Grasslands
Environmental Management, 2011Co-Authors: C J Stevens, Roland Bobbink, K. A. Wotherspoon, D. Alard, P. A. Aarrestad, A. Bleeker, Martin Diekmann, N. B. Dise, David J G Gowing, C. DupréAbstract:There is a growing evidence base demonstrating that atmospheric Nitrogen Deposition presents a threat to biodiversity and ecosystem function in acid grasslands in Western Europe. Here, we report the findings of a workshop held for European policy makers to assess the perceived importance of reactive Nitrogen Deposition for grassland conservation, identify areas for policy development in Europe and assess the potential for managing and mitigating the impacts of Nitrogen Deposition. The importance of Nitrogen as a pollutant is already recognized in European legislation, but there is little emphasis in policy on the evaluation of changes in biodiversity due to Nitrogen. We assess the potential value of using typical species, as defined in the European Union Habitats Directive, for determining the impact of Nitrogen Deposition on acid grasslands. Although some species could potentially be used as indicators of Nitrogen Deposition, many of the typical species do not respond strongly to Nitrogen Deposition and are unlikely to be useful for identifying impact on an individual site. We also discuss potential mitigation measures and novel ways in which emissions from agriculture could be reduced.
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The impact of Nitrogen Deposition on acid grasslands in the Atlantic region of Europe.
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:A survey of 153 acid grasslands from the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is changing plant species composition and soil and plant-tissue chemistry. Across the Deposition gradient (2–44 kg N ha−1 yr−1) grass richness as a proportion of total species richness increased whereas forb richness decreased. Soil C:N ratio increased, but soil extractable nitrate and ammonium concentrations did not show any relationship with Nitrogen Deposition. The above-ground tissue Nitrogen contents of three plant species were examined: Agrostis capillaris (grass), Galium saxatile (forb) and Rhytidiadelphus squarrosus (bryophyte). The tissue Nitrogen content of neither vascular plant species showed any relationship with Nitrogen Deposition, but there was a weak positive relationship between R. squarrosus Nitrogen content and Nitrogen Deposition. None of the species showed strong relationships between above-ground tissue N:P or C:N and Nitrogen Deposition, indicating that they are not good indicators of Deposition rate.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Abstract Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha −1 yr −1 ) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha−1 yr−1) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range. Atmospheric Nitrogen Deposition is reducing biodiversity in grasslands across Europe.
David J G Gowing - One of the best experts on this subject based on the ideXlab platform.
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Addressing the Impact of Atmospheric Nitrogen Deposition on Western European Grasslands
Environmental Management, 2011Co-Authors: C J Stevens, Roland Bobbink, K. A. Wotherspoon, D. Alard, P. A. Aarrestad, A. Bleeker, Martin Diekmann, N. B. Dise, David J G Gowing, C. DupréAbstract:There is a growing evidence base demonstrating that atmospheric Nitrogen Deposition presents a threat to biodiversity and ecosystem function in acid grasslands in Western Europe. Here, we report the findings of a workshop held for European policy makers to assess the perceived importance of reactive Nitrogen Deposition for grassland conservation, identify areas for policy development in Europe and assess the potential for managing and mitigating the impacts of Nitrogen Deposition. The importance of Nitrogen as a pollutant is already recognized in European legislation, but there is little emphasis in policy on the evaluation of changes in biodiversity due to Nitrogen. We assess the potential value of using typical species, as defined in the European Union Habitats Directive, for determining the impact of Nitrogen Deposition on acid grasslands. Although some species could potentially be used as indicators of Nitrogen Deposition, many of the typical species do not respond strongly to Nitrogen Deposition and are unlikely to be useful for identifying impact on an individual site. We also discuss potential mitigation measures and novel ways in which emissions from agriculture could be reduced.
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The impact of Nitrogen Deposition on acid grasslands in the Atlantic region of Europe.
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:A survey of 153 acid grasslands from the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is changing plant species composition and soil and plant-tissue chemistry. Across the Deposition gradient (2–44 kg N ha−1 yr−1) grass richness as a proportion of total species richness increased whereas forb richness decreased. Soil C:N ratio increased, but soil extractable nitrate and ammonium concentrations did not show any relationship with Nitrogen Deposition. The above-ground tissue Nitrogen contents of three plant species were examined: Agrostis capillaris (grass), Galium saxatile (forb) and Rhytidiadelphus squarrosus (bryophyte). The tissue Nitrogen content of neither vascular plant species showed any relationship with Nitrogen Deposition, but there was a weak positive relationship between R. squarrosus Nitrogen content and Nitrogen Deposition. None of the species showed strong relationships between above-ground tissue N:P or C:N and Nitrogen Deposition, indicating that they are not good indicators of Deposition rate.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Abstract Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha −1 yr −1 ) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha−1 yr−1) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range. Atmospheric Nitrogen Deposition is reducing biodiversity in grasslands across Europe.
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Identifying indicators of atmospheric Nitrogen Deposition in calcifugous grasslands
2009Co-Authors: C J Stevens, N. B. Dise, Lindsay C. Maskell, Smart S.m., Caporn S.j.m., David J G GowingAbstract:Atmospheric Deposition of Nitrogen has become a serious concern for nature conservation managers and policy makers. It has the potential to reduce species richness, increase the graminoid component of the sward, encourage species typical of more fertile conditions and alter the soil biogeochemistry of grasslands. Calcifugous grasslands (grasslands found on acid soils) are among the most sensitive to N Deposition due to their poorly buffered soils and species typical of nutrient poor environments. Indicators have an important role to play in detecting the impact of Nitrogen Deposition on sites of conservation importance and assessing conservation status. This study investigates potential indicators of Nitrogen Deposition impacts that could be incorporated into site condition monitoring programmes such as the UK Common Standards Monitoring. Using two national surveys of calcifugous grasslands we examined the potential for using: the presence or absence of indicator species, the cover of indicator species, the species richness and richness of functional groups, and the cover of functional groups as indicators of N Deposition impacts. Of all the potential indicators investigated, graminoid:forb ratio was found to be the best indicator of N Deposition impacts. It showed a significant relationship to N Deposition in both data sets and is quick and easy to assess in the field. Vegetation indicators must be used with caution as there is potential for vegetation management regime and nutrients from other sources to cause similar changes in species composition. Consideration must be given to these before attributing changes to Nitrogen Deposition.
Giorgio Matteucci - One of the best experts on this subject based on the ideXlab platform.
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Reduction of forest soil respiration in response to Nitrogen Deposition
Nature Geoscience, 2010Co-Authors: I. A. Janssens, JR. GRACE, W. Dieleman, J.-a. Subke, A. Dolman, Ruben Ceulemans, Sebastiaan Luyssaert, Philippe Ciais, Markus Reichstein, Giorgio MatteucciAbstract:The use of fossil fuels and fertilizers has increased the amount of biologically reactive Nitrogen in the atmosphere over the past century. As a consequence, forests in industrialized regions have experienced greater rates of Nitrogen Deposition in recent decades. This unintended fertilization has stimulated forest growth, but has also affected soil microbial activity, and thus the recycling of soil carbon and nutrients. A meta-analysis suggests that Nitrogen Deposition impedes organic matter decomposition, and thus stimulates carbon sequestration, in temperate forest soils where Nitrogen is not limiting microbial growth. The concomitant reduction in soil carbon emissions is substantial, and equivalent in magnitude to the amount of carbon taken up by trees owing to Nitrogen fertilization. As atmospheric Nitrogen levels continue to rise, increased Nitrogen Deposition could spread to older, more weathered soils, as found in the tropics; however, soil carbon cycling in tropical forests cannot yet be assessed.
David Fowler - One of the best experts on this subject based on the ideXlab platform.
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The impact of Nitrogen Deposition on acid grasslands in the Atlantic region of Europe.
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:A survey of 153 acid grasslands from the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is changing plant species composition and soil and plant-tissue chemistry. Across the Deposition gradient (2–44 kg N ha−1 yr−1) grass richness as a proportion of total species richness increased whereas forb richness decreased. Soil C:N ratio increased, but soil extractable nitrate and ammonium concentrations did not show any relationship with Nitrogen Deposition. The above-ground tissue Nitrogen contents of three plant species were examined: Agrostis capillaris (grass), Galium saxatile (forb) and Rhytidiadelphus squarrosus (bryophyte). The tissue Nitrogen content of neither vascular plant species showed any relationship with Nitrogen Deposition, but there was a weak positive relationship between R. squarrosus Nitrogen content and Nitrogen Deposition. None of the species showed strong relationships between above-ground tissue N:P or C:N and Nitrogen Deposition, indicating that they are not good indicators of Deposition rate.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Abstract Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha −1 yr −1 ) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha−1 yr−1) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range. Atmospheric Nitrogen Deposition is reducing biodiversity in grasslands across Europe.
Martin Diekmann - One of the best experts on this subject based on the ideXlab platform.
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Addressing the Impact of Atmospheric Nitrogen Deposition on Western European Grasslands
Environmental Management, 2011Co-Authors: C J Stevens, Roland Bobbink, K. A. Wotherspoon, D. Alard, P. A. Aarrestad, A. Bleeker, Martin Diekmann, N. B. Dise, David J G Gowing, C. DupréAbstract:There is a growing evidence base demonstrating that atmospheric Nitrogen Deposition presents a threat to biodiversity and ecosystem function in acid grasslands in Western Europe. Here, we report the findings of a workshop held for European policy makers to assess the perceived importance of reactive Nitrogen Deposition for grassland conservation, identify areas for policy development in Europe and assess the potential for managing and mitigating the impacts of Nitrogen Deposition. The importance of Nitrogen as a pollutant is already recognized in European legislation, but there is little emphasis in policy on the evaluation of changes in biodiversity due to Nitrogen. We assess the potential value of using typical species, as defined in the European Union Habitats Directive, for determining the impact of Nitrogen Deposition on acid grasslands. Although some species could potentially be used as indicators of Nitrogen Deposition, many of the typical species do not respond strongly to Nitrogen Deposition and are unlikely to be useful for identifying impact on an individual site. We also discuss potential mitigation measures and novel ways in which emissions from agriculture could be reduced.
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The impact of Nitrogen Deposition on acid grasslands in the Atlantic region of Europe.
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:A survey of 153 acid grasslands from the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is changing plant species composition and soil and plant-tissue chemistry. Across the Deposition gradient (2–44 kg N ha−1 yr−1) grass richness as a proportion of total species richness increased whereas forb richness decreased. Soil C:N ratio increased, but soil extractable nitrate and ammonium concentrations did not show any relationship with Nitrogen Deposition. The above-ground tissue Nitrogen contents of three plant species were examined: Agrostis capillaris (grass), Galium saxatile (forb) and Rhytidiadelphus squarrosus (bryophyte). The tissue Nitrogen content of neither vascular plant species showed any relationship with Nitrogen Deposition, but there was a weak positive relationship between R. squarrosus Nitrogen content and Nitrogen Deposition. None of the species showed strong relationships between above-ground tissue N:P or C:N and Nitrogen Deposition, indicating that they are not good indicators of Deposition rate.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Abstract Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha −1 yr −1 ) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range.
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Nitrogen Deposition threatens species richness of grasslands across Europe
Environmental Pollution, 2010Co-Authors: C J Stevens, Roland Bobbink, D. Alard, A. Bleeker, Martin Diekmann, David J G Gowing, Cecilia Dupre, Edu Dorland, Cassandre Gaudnik, David FowlerAbstract:Evidence from an international survey in the Atlantic biogeographic region of Europe indicates that chronic Nitrogen Deposition is reducing plant species richness in acid grasslands. Across the Deposition gradient in this region (2–44 kg N ha−1 yr−1) species richness showed a curvilinear response, with greatest reductions in species richness when Deposition increased from low levels. This has important implications for conservation policies, suggesting that to protect the most sensitive grasslands resources should be focussed where Deposition is currently low. Soil pH is also an important driver of species richness indicating that the acidifying effect of Nitrogen Deposition may be contributing to species richness reductions. The results of this survey suggest that the impacts of Nitrogen Deposition can be observed over a large geographical range. Atmospheric Nitrogen Deposition is reducing biodiversity in grasslands across Europe.
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Effects of Nitrogen Deposition on field layer vegetation in south Swedish oak forests
Environmental Pollution, 1999Co-Authors: Jörg Brunet, Martin Diekmann, Ursula Falkengren-grerupAbstract:The influence of atmospheric Nitrogen Deposition on mixed-oak forest vegetation along a Deposition gradient in south Sweden was studied using multivariate methods. The main vegetation gradients were largely controlled by soil acidity, Nitrogen supply, canopy composition and the location of the sample plots. The results suggest that Nitrogen Deposition has affected the field layer vegetation directly by increased Nitrogen availability and indirectly by accelerating soil acidification. A close correlation between Nitrogen Deposition and longitude/latitude does not allow a sharp separation between effects of Deposition and other geographically controlled factors. However, according to time series studies, 20 of the 30 field layer species that are most closely associated with high Nitrogen Deposition in our study have increased in frequency in areas with high Deposition during the past decades. This group of field layer species includes many species generally considered as nitrophilous, but also several acid-tolerant species.