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| 1 | Nitrogen deposition and reduction of terrestrial biodiversity:Evidence from temperate grasslands显示文摘Biodiversity is thought to be essential for ecosystem stability, function and long-term sustainability. Since nitrogen is the limiting nutrient for plant growth in many terrestrial ecosystems, reactive nitrogen has the potential to reduce the diversity of terrestrial vegetation and associated biota through favouring species adapted to quickly exploiting available nutrients. Although the potential has long been recognised, only recently has enough evidence come together to show beyond reasonable doubt that these changes are already occurring. Linked together, experimental, regional/e.rnpirical, and time-series research provide a powerful argument that enhanced deposition of reactive nitrogen across Great Britain, and potentially the rest of Europe, has resulted in a significant and ongoing decline in grassland species richness and diversity. | Nancy B.Dise Carly J.Stevens | 2005 | Science China(Life Sciences)2005，48，z2： | 8 |
| 2 | Effects of the frequency and the rate of N enrichment on community structure in a temperate grassland显示文摘Aims Nitrogen(N)enrichment caused by human activities threatens bio-diversity and alters plant community composition and structure.It has been found that heavy and infrequent N inputs may over-estimate species extinction,but it remains unclear whether plant community structure will equally respond to frequent reactive N enriched conditions.Methods We independently manipulated the rates and the frequencies of N addition in a temperate steppe,northern China,between 2008 and 2013.Important Findings We found that plant community structure changes,measured by‘Euclidean distance’involving species richness,composition and productivity,were significantly positively related to increasing N enrichment rates rather than frequencies.Changes in aboveground net primary productivity(ANPP),plant species richness and shifts in dominant species were observed.Community ANPP increased with N enrichment,whereas species richness reduced.The frequency of N enrichment increased species richness but had no impacts on community ANPP and the relative ANPP of the two dominant spe-cies,C3 perennial bunchgrass Stipa grandis and C3 perennial rhi-zome grass Leymus chinensis.The ANPP and relative ANPP of the two dominant species were significantly negatively correlated with each other.Moreover,changes in the relative ANPP of S.grandis was negatively associated with the changes in community structure.After 5 years’treatment,direct influence of the frequency of N en-richment on plant community structure was not observed,but the effects of the rate of N enrichment were apparent.Our results sug-gested that further study in various ecosystems and with long-term and well-controlled comparisons the frequency vs.the rate of N enrichment may still be needed. | Yunhai Zhang Jing Wang Carly J.Stevens Xiaotao Lü Nianpeng He Changhui Wang Xingguo Han | 2018 | Journal of Plant Ecology2018，11，5： | 2 |
| 3 | Effect of nitrogen addition, form and clipping on competitive interactions between grassland species显示文摘Aims Although the effects of N addition on plant biomass are well understood,we know a lot less about the importance of N form even though some studies have shown different impacts from reduced and oxidized forms of N.Furthermore,responses to grazing are likely to interact with the response to N addition.This experiment investigates the interactive effects of N addition and form with clipping on competition between three grassland species.Methods The three species(Anthoxanthum odoratum L.,Plantago lanceolata L.and Prunella vulgaris L.)were grown alone and in combination with factorial additions of deionized water,sodium nitrate and ammonium chloride,and a clipping treatment.Above-and belowground biomass was harvested after 4 months.Important Findings In monocultures,the results show increases in biomass with N addition,but clipping resulted in fewer changes with species displaying varying degrees of growth compensation.A.odoratum was the strongest competitor when grown with other species.In monocultures without clipping,N form was not important,but in the presence of clipping and in different species combinations,N form became important.Significant two-and three-way interactive effects were observed showing that complex interactions exist between N addition,clipping and species identity.The results have important implications when considering the effects of N deposition. | Carly J.Stevens David J.G.Gowing | 2014 | Journal of Plant Ecology2014，7，3： | 2 |
| 4 | Serum S100β显示文摘 | Andrew A.Kanner NicolaMarchi VincentFazio Marc R.Mayberg Michael T.Koltz VitalySiomin Glen H. J.Stevens ThomasMasaryk BarbaraAyumar Michael A.Vogelbaum Gene H.Barnett DamirJanigro | 2003 | Cancer2003，，11： | 1 |
| 5 | Systemic endotoxin levels in chronic indolent periodontal infections显示文摘 | J. L.Ebersole J.Stevens M. J.Steffen D.Dawson III M. J.Novak | 2010 | Journal of Periodontal Research2010，，1： | 1 |
| 6 | Reassessment of historical sections from the Paleogene marine margin of the Congo Basin reveals an almost complete absence of Danian deposits显示文摘The early Paleogene is critical for understanding global biodiversity patterns in modern ecosystems. During this interval, Southern Hemisphere continents were largely characterized by isolation and faunal endemism following the breakup of Gondwana. Africa has been proposed as an important source area for the origin of several marine vertebrate groups but its Paleogene record is poorly sampled, especially from sub-Saharan Africa. To document the early Paleogene marine ecosystems of Central Africa, we revised the stratigraphic context of sedimentary deposits from three fossil-rich vertebrate localities: the Landana section in the Cabinda exclave(Angola), and the Manzadi and Bololo localities in western Democratic Republic of Congo.We provide more refined age constraints for these three localities based on invertebrate and vertebrate faunas, foraminiferal and dinoflagellate cyst assemblages, and carbon isotope records. We find an almost complete absence of Danian-aged rocks in the Landana section, contrary to prevailing interpretations over the last half a century(only the layer 1, at the base of the section, seems to be Danian). Refining the age of these Paleocene layers is crucial for analyzing fish evolution in a global framework, with implications for the early appearance of Scombridae(tunas and mackerels) and Tetraodontiformes(puffer fishes). The combination of vertebrate fossil records from Manzadi and Landana sections suggests important environmental changes around the K/Pg transition characterized by an important modification of the ichthyofauna. A small faunal shift may have occurred during the Selandian. More dramatic is the distinct decrease in overall richness that lasts from the Selandian to the Ypresian. The Lutetian of West Central Africa is characterized by the first appearance of numerous cartilaginous and bony fishes. Our analysis of the ichthyofauna moreover indicates two periods of faunal exchanges: one during the Paleocene, where Central Africa appears to have been a source for the European marine fauna, and another during the Eocene when Europe was the source of the Central Africa fauna. These data indicate that Central Africa has had connections with the Tethyian realm. | Floréal Solé Corentin Noiret Delphine Desmares Sylvain Adnet Louis Taverne Thierry De Putter Florias Mees Johan Yans Thomas Steeman Stephen Louwye Annelise Folie Nancy J.Stevens Gregg F.Gunnell Daniel Baudet Nicole Kitambala Yaya Thierry Smith | 2019 | Geoscience Frontiers2019，10，3： | 0 |
| 7 | Sustainable plasticulture in Chinese agriculture: a review of challenges and routes to achieving long-term food and ecosecurity显示文摘Plastic pollution is global concern, affecting most aspects of global food production systems. Plasticulture, a practice used in agriculture to improve crop quality and quantity, among other factors, is a significant source of plastic pollution. This review examines the extent of plasticulture in China, the implications of the practice across decades of use and the legislative instruments used to resolve those issues. It briefly assesses the effectiveness of these policies and proposes possible future innovations to promote increases in long-term food and eco-security, where sustainable plasticulture is a key agent for change. While plasticulture has increased agricultural productivity in growth-limiting conditions, plastic pollution in agricultural soils has become acute in China. Consequently, plastic pollution is having deleterious effects on soil health and in turn, crop productivity in China. Plastic pollution in agriculture is a multifaceted issue and so proposed solutions should be informed by this complexity. Current measures do not reflect a holistic approach to solving this socioecological challenge and adopt a top-down approach, with little or no supportive mechanisms. Future recommendations need to consider the particular set of conditions that influence the production, use and end-of-life management of agriplastics,specific to the environmental, economic and social conditions in each location. | Samuel J.CUSWORTH William J.DAVIES Martin R.MCAINSH Carly J.STEVENS Weilu WANG | 2024 | Frontiers of Agricultural Science and Engineering2024，11，1： | 0 |
| 8 | RESEARCH PROGRESS ON THE IMPACT OF NITROGEN DEPOSITION ON GLOBAL GRASSLANDS显示文摘Grasslands are globally-important ecosystems providing critical ecosystem services.The species composition and characteristics of grasslands vary considerably across the planet with a wide variety of different grasslands found.However,in many regions grasslands have been impacted by atmospheric nitrogen deposition originating from anthropogenic activities with effects on productivity,species composition and diversity widely reported.Impacts vary across grassland habitats but many show declines in species richness and increases in biomass production related to soil eutrophication and acidification.At a continental level,there is considerable variation in the research effort that has been put into understanding the impacts of nitrogen deposition.In Europe,North America and parts of Asia,although there are unanswered research questions,there is a good understanding of N deposition impacts in most grassland habitats.This is not the case in other regions with large knowledge gaps in some parts of the world.This paper reviews the impacts of N deposition on grasslands around the world,highlighting recent advances and areas where research is still needed. | Carly J.STEVENS Sofía BASTO Michael DBELL Tianxiang HAO Kevin KIRKMAN Raul OCHOA-HUESO | 2022 | Frontiers of Agricultural Science and Engineering2022，9，3： | 0 |
| 9 | 检测地面温度记录中的气候信号显示文摘利用最佳信号检测理论于100年的地面温度资料中寻找与4个特定辐射强迫的气候响应。分析中所用的资料来源于地球上的36个单元,而且被限定在0.06~0.13r/a的频带(16.67~7.69a)内。估算了气候对太阳变率、火山气溶胶、温室气体和人类活动产生的气溶胶的响应强度。最佳滤波器由一个用二维能量平衡模式(EBM)计算出的信号波形组成。最佳权重是用地球物理流体动力学实验室(GFDL)和Max-Plank研究所耦合的海气模式的1000年控制试验和噪声强迫的EBM10000年控制试验计算得到的。作者还利用了GFDL混和层模式的1000年试验。结果这4个独立的模式有合理的一致性。我们发现,垂直于其他信号的火山分量非常强,且很显著。与此类似,垂直于其他信号的温室气体分量也非常强且很显著。当所有4个气候强迫组合时,气候响应超过噪音水平的3个标准差。 | Gerald R.North Mark J.Stevens | 1999 | 气象科技1999，27，2： | 0 |
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