@article{BluethgenDormannPratietal.2012, author = {Bl{\"u}thgen, Nico and Dormann, Carsten F. and Prati, Daniel and Klaus, Valentin H. and Kleinebecker, Till and Hoelzel, Norbert and Alt, Fabian and Boch, Steffen and Gockel, Sonja and Hemp, Andreas and M{\"u}ller, J{\"o}rg and Nieschulze, Jens and Renner, Swen C. and Sch{\"o}ning, Ingo and Schumacher, Uta and Socher, Stephanie A. and Wells, Konstans and Birkhofer, Klaus and Buscot, Francois and Oelmann, Yvonne and Rothenw{\"o}hrer, Christoph and Scherber, Christoph and Tscharntke, Teja and Weiner, Christiane N. and Fischer, Markus and Kalko, Elisabeth K. V. and Linsenmair, Karl Eduard and Schulze, Ernst-Detlef and Weisser, Wolfgang W.}, title = {A quantitative index of land-use intensity in grasslands integrating mowing, grazing and fertilization}, series = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, volume = {13}, journal = {Basic and applied ecology : Journal of the Gesellschaft f{\"u}r {\"O}kologie}, number = {3}, publisher = {Elsevier}, address = {Jena}, issn = {1439-1791}, doi = {10.1016/j.baae.2012.04.001}, pages = {207 -- 220}, year = {2012}, abstract = {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.}, language = {en} } @article{NaetherFoeselNaegeleetal.2012, author = {N{\"a}ther, Astrid and F{\"o}sel, B{\"a}rbel U. and N{\"a}gele, Verena and W{\"u}st, Pia K. and Weinert, Jan and Bonkowski, Michael and Alt, Fabian and Oelmann, Yvonne and Polle, Andrea and Lohaus, Gertrud and Gockel, Sonja and Hemp, Andreas and Kalko, Elisabeth K. V. and Linsenmair, Karl Eduard and Pfeiffer, Simone and Renner, Swen and Sch{\"o}ning, Ingo and Weisser, Wolfgang W. and Wells, Konstans and Fischer, Markus and Overmann, J{\"o}rg and Friedrich, Michael W.}, title = {Environmental factors affect acidobacterial communities below the subgroup level in Grassland and Forest Soils}, series = {Applied and environmental microbiology}, volume = {78}, journal = {Applied and environmental microbiology}, number = {20}, publisher = {American Society for Microbiology}, address = {Washington}, issn = {0099-2240}, doi = {10.1128/AEM.01325-12}, pages = {7398 -- 7406}, year = {2012}, abstract = {In soil, Acidobacteria constitute on average 20\% of all bacteria, are highly diverse, and are physiologically active in situ. However, their individual functions and interactions with higher taxa in soil are still unknown. Here, potential effects of land use, soil properties, plant diversity, and soil nanofauna on acidobacterial community composition were studied by cultivation-independent methods in grassland and forest soils from three different regions in Germany. The analysis of 16S rRNA gene clone libraries representing all studied soils revealed that grassland soils were dominated by subgroup Gp6 and forest soils by subgroup Gp1 Acidobacteria. The analysis of a large number of sites (n = 57) by 16S rRNA gene fingerprinting methods (terminal restriction fragment length polymorphism [T-RFLP] and denaturing gradient gel electrophoresis [DGGE]) showed that Acidobacteria diversities differed between grassland and forest soils but also among the three different regions. Edaphic properties, such as pH, organic carbon, total nitrogen, C/N ratio, phosphorus, nitrate, ammonium, soil moisture, soil temperature, and soil respiration, had an impact on community composition as assessed by fingerprinting. However, interrelations with environmental parameters among subgroup terminal restriction fragments (T-RFs) differed significantly, e.g., different Gp1 T-RFs correlated positively or negatively with nitrogen content. Novel significant correlations of Acidobacteria subpopulations (i.e., individual populations within subgroups) with soil nanofauna and vascular plant diversity were revealed only by analysis of clone sequences. Thus, for detecting novel interrelations of environmental parameters with Acidobacteria, individual populations within subgroups have to be considered.}, language = {en} }