@article{SimonsGossnerLewinsohnetal.2014, author = {Simons, Nadja K. and Gossner, Martin M. and Lewinsohn, Thomas M. and Boch, Steffen and Lange, Markus and M{\"u}ller, J{\"o}rg and Pasalic, Esther and Socher, Stephanie A. and T{\"u}rke, Manfred and Fischer, Markus and Weisser, Wolfgang W.}, title = {Resource-mediated indirect effects of grassland management on arthropod diversity}, series = {PLoS one}, volume = {9}, journal = {PLoS one}, number = {9}, publisher = {PLoS}, address = {San Fransisco}, issn = {1932-6203}, doi = {10.1371/journal.pone.0107033}, pages = {12}, year = {2014}, abstract = {Intensive land use is a driving force for biodiversity decline in many ecosystems. In semi-natural grasslands, land-use activities such as mowing, grazing and fertilization affect the diversity of plants and arthropods, but the combined effects of different drivers and the chain of effects are largely unknown. In this study we used structural equation modelling to analyse how the arthropod communities in managed grasslands respond to land use and whether these responses are mediated through changes in resource diversity or resource quantity (biomass). Plants were considered resources for herbivores which themselves were considered resources for predators. Plant and arthropod (herbivores and predators) communities were sampled on 141 meadows, pastures and mown pastures within three regions in Germany in 2008 and 2009. Increasing land-use intensity generally increased plant biomass and decreased plant diversity, mainly through increasing fertilization. Herbivore diversity decreased together with plant diversity but showed no response to changes in plant biomass. Hence, land-use effects on herbivore diversity were mediated through resource diversity rather than quantity. Land-use effects on predator diversity were mediated by both herbivore diversity (resource diversity) and herbivore quantity (herbivore biomass), but indirect effects through resource quantity were stronger. Our findings highlight the importance of assessing both direct and indirect effects of land-use intensity and mode on different trophic levels. In addition to the overall effects, there were subtle differences between the different regions, pointing to the importance of regional land-use specificities. Our study underlines the commonly observed strong effect of grassland land use on biodiversity. It also highlights that mechanistic approaches help us to understand how different land-use modes affect biodiversity.}, language = {en} } @article{GossnerLewinsohnKahletal.2016, author = {Gossner, Martin M. and Lewinsohn, Thomas M. and Kahl, Tiemo and Grassein, Fabrice and Boch, Steffen and Prati, Daniel and Birkhofer, Klaus and Renner, Swen C. and Sikorski, Johannes and Wubet, Tesfaye and Arndt, Hartmut and Baumgartner, Vanessa and Blaser, Stefan and Bl{\"u}thgen, Nico and B{\"o}rschig, Carmen and Buscot, Francois and Diek{\"o}tter, Tim and Jorge, Leonardo Re and Jung, Kirsten and Keyel, Alexander C. and Klein, Alexandra-Maria and Klemmer, Sandra and Krauss, Jochen and Lange, Markus and M{\"u}ller, J{\"o}rg and Overmann, J{\"o}rg and Pasalic, Esther and Penone, Caterina and Perovic, David J. and Purschke, Oliver and Schall, Peter and Socher, Stephanie A. and Sonnemann, Ilja and Tschapka, Marco and Tscharntke, Teja and T{\"u}rke, Manfred and Venter, Paul Christiaan and Weiner, Christiane N. and Werner, Michael and Wolters, Volkmar and Wurst, Susanne and Westphal, Catrin and Fischer, Markus and Weisser, Wolfgang W. and Allan, Eric}, title = {Land-use intensification causes multitrophic homogenization of grassland communities}, series = {Nature : the international weekly journal of science}, volume = {540}, journal = {Nature : the international weekly journal of science}, publisher = {Nature Publ. Group}, address = {London}, issn = {0028-0836}, doi = {10.1038/nature20575}, pages = {266 -- +}, year = {2016}, abstract = {Land-use intensification is a major driver of biodiversity loss(1,2). Alongside reductions in local species diversity, biotic homogenization at larger spatial scales is of great concern for conservation. Biotic homogenization means a decrease in beta-diversity (the compositional dissimilarity between sites). Most studies have investigated losses in local (alpha)-diversity(1,3) and neglected biodiversity loss at larger spatial scales. Studies addressing beta-diversity have focused on single or a few organism groups (for example, ref. 4), and it is thus unknown whether land-use intensification homogenizes communities at different trophic levels, above-and belowground. Here we show that even moderate increases in local land-use intensity (LUI) cause biotic homogenization across microbial, plant and animal groups, both above- and belowground, and that this is largely independent of changes in alpha-diversity. We analysed a unique grassland biodiversity dataset, with abundances of more than 4,000 species belonging to 12 trophic groups. LUI, and, in particular, high mowing intensity, had consistent effects on beta-diversity across groups, causing a homogenization of soil microbial, fungal pathogen, plant and arthropod communities. These effects were nonlinear and the strongest declines in beta-diversity occurred in the transition from extensively managed to intermediate intensity grassland. LUI tended to reduce local alpha-diversity in aboveground groups, whereas the alpha-diversity increased in belowground groups. Correlations between the alpha-diversity of different groups, particularly between plants and their consumers, became weaker at high LUI. This suggests a loss of specialist species and is further evidence for biotic homogenization. The consistently negative effects of LUI on landscape-scale biodiversity underscore the high value of extensively managed grasslands for conserving multitrophic biodiversity and ecosystem service provision. Indeed, biotic homogenization rather than local diversity loss could prove to be the most substantial consequence of land-use intensification.}, language = {en} }