TY - JOUR A1 - Hancock, Christine A1 - Wäschke, Nicole A1 - Schumacher, Uta A1 - Linsenmair, Karl Eduard A1 - Meiners, Torsten A1 - Obermaier, Elisabeth T1 - Fertilizer application decreases insect abundance on Plantago lanceolata - a large-scale experiment in three geographic regions JF - Arthropod-plant interactions : an international journal devoted to studies on interactions of insects, mites, and other arthropods with plants N2 - Humans have substantially altered the nitrogen cycle of ecosystems through the application of agricultural fertilizer. Fertilization may not only affect plant species diversity, but also insect dynamics by altering plant nitrogen supplies. We investigated the effect of experimental fertilization on the vegetation, with the ribwort plantain as the focal plant, and on higher trophic levels on differently managed grasslands throughout Germany. Over a period of 2 years, we examined two specialist herbivores and their parasitoid on Plantago lanceolata L., and the composition and structure of the surrounding vegetation. Over 70 sites in three geographic regions, within the large-scale project "German Biodiversity Exploratories", were included in the study. The model system consisted of the host plant P. lanceolata L., the monophagous weevils Mecinus labilis Herbst and M. pascuorum Gyllenhal, and their parasitoid Mesopolobus incultus Walker. Fertilization decreased plant species richness and host plant abundance, whereas it enhanced the total vegetation growth. The increased size and heigher leaf nitrogen content did not improve herbivore performance. On the contrary, the abundance of the two herbivores was decreased by fertilization. The parasitoid depended on the abundance of one of its hosts, M. pascuorum (positively density-dependent). Reduced herbivore abundance due to fertilization might be explained by a lower abundance of the host plant, a lower stalk number, and by changed patterns of host localization within higher vegetation. Fertilization negatively affected the third trophic level by cascading up via host abundance. The relationships between fertilization, surrounding vegetation and the tritrophic system were measured throughout the three regions and over the 2-year period. Our findings present consequences of intensification for a plant-herbivore-parasitoid system, and may have significant implications for the conservation of multitrophic systems in managed grasslands. KW - Fertilization KW - Nitrogen KW - Tritrophic interaction KW - Plant species richness KW - Grassland management KW - Vegetation structure Y1 - 2013 U6 - https://doi.org/10.1007/s11829-012-9237-9 SN - 1872-8855 SN - 1872-8847 VL - 7 IS - 2 SP - 147 EP - 158 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Fischer, Markus A1 - Bossdorf, Oliver A1 - Gockel, Sonja A1 - Haensel, Falk A1 - Hemp, Andreas A1 - Hessenmoeller, Dominik A1 - Korte, Gunnar A1 - Nieschulze, Jens A1 - Pfeiffer, Simone A1 - Prati, Daniel A1 - Renner, Swen A1 - Schoening, Ingo A1 - Schumacher, Uta A1 - Wells, Konstans A1 - Buscot, Francois A1 - Kalko, Elisabeth K. V. A1 - Linsenmair, Karl Eduard A1 - Schulze, Ernst-Detlef A1 - Weisser, Wolfgang W. T1 - Implementing large-scale and long-term functional biodiversity research : the biodiversity exploratories N2 - Functional biodiversity research explores drivers and functional consequences of biodiversity changes Land use change is a major driver of changes of biodiversity and of biogeochemical and biological ecosystem processes and services However, land use effects on genetic and species diversity are well documented only for a few taxa and trophic networks We hardly know how different components of biodiversity and their responses to land use change are interrelated and very little about the simultaneous, and interacting, effects of land use on multiple ecosystem processes and services Moreover, we do not know to what extent land use effects on ecosystem processes and services are mediated by biodiversity change Thus, overall goals are on the one hand to understand the effects of land use on biodiversity and on the other to understand the modifying role of biodiversity change for land-use effects on ecosystem processes, including biogeochemical cycles To comprehensively address these Important questions, we recently established a new large-scale and long-term project for functional biodiversity, the Biodiversity Exploratories (www biodiversity-exploratories de) They comprise a hierarchical set of standardized field plots in three different regions of Germany covering manifold management types and intensities in grasslands and forests They serve as a joint research platform for currently 40 projects involving over 300 people studying various aspects of the relationships between land use biodiversity and ecosystem processes through monitoring, comparative observation and experiments We introduce guiding questions, concept and design of the Biodiversity Exploratories - including main aspects of selection and implementation of field plots and project structure - and we discuss the significance of this approach for further functional biodiversity research This includes the crucial relevance of a common study design encompassing variation in both drivers and outcomes of biodiversity change and ecosystem processes, the interdisciplinary integration of biodiversity and ecosystem researchers, the training of a new generation of integrative biodiversity researchers, and the stimulation of functional biodiversity research in real landscape contexts, in Germany and elsewhere. Y1 - 2010 UR - http://www.sciencedirect.com/science/journal/14391791 U6 - https://doi.org/10.1016/j.baae.2010.07.009 SN - 1439-1791 ER - TY - JOUR A1 - Blüthgen, Nico A1 - Dormann, Carsten F. A1 - Prati, Daniel A1 - Klaus, Valentin H. A1 - Kleinebecker, Till A1 - Hoelzel, Norbert A1 - Alt, Fabian A1 - Boch, Steffen A1 - Gockel, Sonja A1 - Hemp, Andreas A1 - Müller, Jörg A1 - Nieschulze, Jens A1 - Renner, Swen C. A1 - Schöning, Ingo A1 - Schumacher, Uta A1 - Socher, Stephanie A. A1 - Wells, Konstans A1 - Birkhofer, Klaus A1 - Buscot, Francois A1 - Oelmann, Yvonne A1 - Rothenwöhrer, Christoph A1 - Scherber, Christoph A1 - Tscharntke, Teja A1 - Weiner, Christiane N. A1 - Fischer, Markus A1 - Kalko, Elisabeth K. V. A1 - Linsenmair, Karl Eduard A1 - Schulze, Ernst-Detlef A1 - Weisser, Wolfgang W. T1 - A quantitative index of land-use intensity in grasslands integrating mowing, grazing and fertilization JF - Basic and applied ecology : Journal of the Gesellschaft für Ökologie N2 - Land use is increasingly recognized as a major driver of biodiversity and ecosystem functioning in many current research projects. In grasslands, land use is often classified by categorical descriptors such as pastures versus meadows or fertilized versus unfertilized sites. However, to account for the quantitative variation of multiple land-use types in heterogeneous landscapes, a quantitative, continuous index of land-use intensity (LUI) is desirable. Here we define such a compound, additive LUI index for managed grasslands including meadows and pastures. The LUI index summarizes the standardized intensity of three components of land use, namely fertilization, mowing, and livestock grazing at each site. We examined the performance of the LUI index to predict selected response variables on up to 150 grassland sites in the Biodiversity Exploratories in three regions in Germany(Alb, Hainich, Schorlheide). We tested the average Ellenberg nitrogen indicator values of the plant community, nitrogen and phosphorus concentration in the aboveground plant biomass, plant-available phosphorus concentration in the top soil, and soil C/N ratio, and the first principle component of these five response variables. The LUI index significantly predicted the principal component of all five response variables, as well as some of the individual responses. Moreover, vascular plant diversity decreased significantly with LUI in two regions (Alb and Hainich). Inter-annual changes in management practice were pronounced from 2006 to 2008, particularly due to variation in grazing intensity. This rendered the selection of the appropriate reference year(s) an important decision for analyses of land-use effects, whereas details in the standardization of the index were of minor importance. We also tested several alternative calculations of a LUI index, but all are strongly linearly correlated to the proposed index. The proposed LUI index reduces the complexity of agricultural practices to a single dimension and may serve as a baseline to test how different groups of organisms and processes respond to land use. In combination with more detailed analyses, this index may help to unravel whether and how land-use intensities, associated disturbance levels or other local or regional influences drive ecological processes. KW - Agro-ecosystems KW - Biodiversity exploratories KW - Grassland management KW - Land-use impacts KW - Livestock density KW - Meadows KW - Nitrogen KW - Pastures Y1 - 2012 U6 - https://doi.org/10.1016/j.baae.2012.04.001 SN - 1439-1791 VL - 13 IS - 3 SP - 207 EP - 220 PB - Elsevier CY - Jena ER -