@misc{LuckeSzameitatGoerlichetal.2014, author = {Lucke, Ulrike and Szameitat, Ulrike and G{\"o}rlich, Petra and Kampe, Heike and Lux, Nadine and Bomhoff, Hartmut and Rudolph, Pascal and J{\"a}ger, Sophie and Ziemer, Franziska and Friess, Nina and Eckardt, Barbara and Joshi, Jasmin Radha and Huwe, Bj{\"o}rn and Zimmermann, Matthias and S{\"u}tterlin, Sabine}, title = {Portal = Studieren im digitalen Zeitalter: E-Learning in Lehre und Studium}, number = {04/2014}, organization = {Universit{\"a}t Potsdam, Referat f{\"u}r Presse- und {\"O}ffentlichkeitsarbeit}, issn = {1618-6893}, doi = {10.25932/publishup-44061}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-440615}, pages = {42}, year = {2014}, abstract = {Aus dem Inhalt: - Studieren im digitalen Zeitalter: E-Learning in Lehre und Studium - Wie Alice im Wunderland - Moose im All}, language = {de} } @article{RottstockJoshiKummeretal.2014, author = {Rottstock, Tanja and Joshi, Jasmin Radha and Kummer, Volker and Fischer, Markus}, title = {Higher plant diversity promotes higher diversity of fungal pathogens, while it decreases pathogen infection per plant}, series = {Ecology : a publication of the Ecological Society of America}, volume = {95}, journal = {Ecology : a publication of the Ecological Society of America}, number = {7}, publisher = {Wiley}, address = {Washington}, issn = {0012-9658}, pages = {1907 -- 1917}, year = {2014}, abstract = {Fungal plant pathogens are common in natural communities where they affect plant physiology, plant survival, and biomass production. Conversely, pathogen transmission and infection may be regulated by plant community characteristics such as plant species diversity and functional composition that favor pathogen diversity through increases in host diversity while simultaneously reducing pathogen infection via increased variability in host density and spatial heterogeneity. Therefore, a comprehensive understanding of multi-host multi-pathogen interactions is of high significance in the context of biodiversity-ecosystem functioning. We investigated the relationship between plant diversity and aboveground obligate parasitic fungal pathogen ("pathogens" hereafter) diversity and infection in grasslands of a long-term, large-scale, biodiversity experiment with varying plant species (1-60 species) and plant functional group diversity (1-4 groups). To estimate pathogen infection of the plant communities, we visually assessed pathogen-group presence (i.e., rusts, powdery mildews, downy mildews, smuts, and leaf-spot diseases) and overall infection levels (combining incidence and severity of each pathogen group) in 82 experimental plots on all aboveground organs of all plant species per plot during four surveys in 2006. Pathogen diversity, assessed as the cumulative number of pathogen groups on all plant species per plot, increased log-linearly with plant species diversity. However, pathogen incidence and severity, and hence overall infection, decreased with increasing plant species diversity. In addition, co-infection of plant individuals by two or more pathogen groups was less likely with increasing plant community diversity. We conclude that plant community diversity promotes pathogen-community diversity while at the same time reducing pathogen infection levels of plant individuals.}, language = {en} } @article{MuellerHeinzeJoshietal.2014, author = {M{\"u}ller, J{\"o}rg and Heinze, Johannes and Joshi, Jasmin Radha and Boch, Steffen and Klaus, Valentin H. and Fischer, Markus and Prati, Daniel}, title = {Influence of experimental soil disturbances on the diversity of plants in agricultural grasslands}, series = {Journal of plant ecology}, volume = {7}, journal = {Journal of plant ecology}, number = {6}, publisher = {Oxford Univ. Press}, address = {Oxford}, issn = {1752-9921}, doi = {10.1093/jpe/rtt062}, pages = {509 -- 517}, year = {2014}, abstract = {Disturbance is supposed to play an important role for biodiversity and ecosystem stability as described by the intermediate disturbance hypothesis (IDH), which predicts highest species richness at intermediate levels of disturbances. In this study, we tested the effects of artificial soil disturbances on diversity of annual and perennial vascular plants and bryophytes in a field experiment in 86 agricultural grasslands differing in land use in two regions of Germany. On each grassland, we implemented four treatments: three treatments differing in application time of soil disturbances and one control. One year after experimental disturbance, we recorded vegetation and measured biomass productivity and bare ground. We analysed the disturbance response taking effects of region and land-use-accompanied disturbance regimes into account. Region and land-use type strongly determined plant species richness. Experimental disturbances had small positive effects on the species richness of annuals, but none on perennials or bryophytes. Bare ground was positively related to species richness of bryophytes. However, exceeding the creation of 12\% bare ground further disturbance had a detrimental effect on bryophyte species richness, which corresponds to the IDH. As biomass productivity was unaffected by disturbance our results indicate that the disturbance effect on species richness of annuals was not due to decreased overall productivity, but rather due to short-term lowered inter- and intraspecific competition at the newly created microsites. Generally, our results highlight the importance of soil disturbances for species richness of annual plants and bryophytes in agricultural grasslands. However, most grasslands were disturbed naturally or by land-use practices and our additional experimental soil disturbances only had a small short-term effect. Overall, total plant diversity in grasslands seemed to be more limited by the availability of propagules rather than by suitable microsites for germination. Thus, nature conservation efforts to increase grassland diversity should focus on overcoming propagule limitation, for instance by additional sowing of seeds, while the creation of additional open patches by disturbance might only be appropriate where natural disturbances are scarce.}, language = {en} }