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Immunofluorescence and confocal microscopy for ex‐vivo diagnosis of melanocytic and non‐melanocytic skin tumors: A pilot study 下载免费PDF全文
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PDGFB as a vascular normalization agent in an ovarian cancer model treated with a gamma‐secretase inhibitor 下载免费PDF全文
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Plant diversity induces shifts in the functional structure and diversity across trophic levels 下载免费PDF全文
Anne Ebeling Michael Rzanny Markus Lange Nico Eisenhauer Lionel R. Hertzog Sebastian T. Meyer Wolfgang W. Weisser 《Oikos》2018,127(2):208-219
Changes to primary producer diversity can cascade up to consumers and affect ecosystem processes. Although the effect of producer diversity on higher trophic groups have been studied, these studies often quantify taxonomy‐based measures of biodiversity, like species richness, which do not necessarily reflect the functioning of these communities. In this study, we assess how plant species richness affects the functional composition and diversity of higher trophic levels and discuss how this might affect ecosystem processes, such as herbivory, predation and decomposition. Based on six different consumer traits, we examined the functional composition of arthropod communities sampled in experimental plots that differed in plant species richness. The two components we focused on were functional variation in the consumer community structure (functional structure) and functional diversity, expressed as functional richness, evenness and divergence. We found a consistent positive effect of plant species richness on the functional richness of herbivores, carnivores, and omnivores, but not decomposers, and contrasting patterns for functional evenness and divergence. Increasing plant species richness shifted the omnivore community to more predatory and less mobile species, and the herbivore community to more specialized and smaller species. This was accompanied by a shift towards more species occurring in the vegetation than in the ground layer. Our study shows that plant species richness strongly affects the functional structure and diversity of aboveground arthropod communities. The observed shifts in body size (herbivores), specialization (herbivores), and feeding mode (omnivores) together with changes in the functional diversity may underlie previously observed increases in herbivory and predation in plant communities of higher diversity. 相似文献
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Bijeesh Kozhikkodan Veettil Sebastian Felipe Ruiz Pereira Ngo Xuan Quang 《Hydrobiologia》2018,814(1):19-30
IPCC predictions indicate an increase in temperatures by 1.5–7°C in some Amazonian regions during the twenty-first century. These changes could disrupt the present distribution patterns of organisms, including wetland plant species. In this work, we determined in microcosms the effects of scenarios combining elevated temperature and atmospheric CO2 concentration on the germination and initial growth of the arborescent Amazonian aquatic macrophyte Montrichardia arborescens. Seeds were germinated, and seedlings produced were monitored over a 5-month period in four microcosms: Control: ambient temperature and CO2 level; Mild: Control + 1.5°C and + 200 ppm CO2; intermediate: control + 2.5°C and + 400 ppm CO2; Extreme: Control + 4.5°C and + 850 ppm of CO2. Rapid light response curves and Fv/Fm values taken in seedlings showed a decrease in electron transportation rate with CO2 and temperature elevation. Mild and Intermediate treatments stimulated biomass production; Extreme treatment and Control produced similar results. The severe climatic changes expected in the future may negatively influence carbon accumulation in M. arborescens. Since aquatic macrophytes in Amazonian wetlands and wetlands worldwide are key plant species, further studies are needed to predict their fate in a global change perspective. 相似文献
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Feng Lu Sundberg Sebastian Ooi Mark K. J. Wu Yu-Huan Wang Meng Bu Zhao-Jun 《Plant and Soil》2018,432(1-2):403-413
Plant and Soil - To test the effects of characteristic ecological gradients in peatlands including oxygen-deficiency and allelopathy on Sphagnum spore persistence. We determined the initial... 相似文献
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Koebernick Nicolai Schlüter Steffen Blaser Sebastian R. G. A. Vetterlein Doris 《Plant and Soil》2018,431(1-2):417-431
Plant and Soil - Root shrinkage in drying soil has been shown repeatedly. The aim of this study was to investigate the dynamics of root-soil contact and its relationship with plant water status... 相似文献