@article{KlausHoelzelBochetal.2013,
  author    = {Klaus, Valentin H. and H{\"o}lzel, Norbert and Boch, Steffen and M{\"u}ller, Jorg and Socher, Stephanie A. and Prati, Daniel and Fischer, Markus and Kleinebecker, Till},
  title     = {Direct and indirect associations between plant species richness and productivity in grasslands regional differences preclude simple generalization of productivity-biodiversity relationships},
  series = {Preslia : the journal of the Czech Botanical Society},
  volume    = {85},
  journal   = {Preslia : the journal of the Czech Botanical Society},
  number    = {2},
  publisher = {Czech Botanical Soc.},
  address   = {Praha},
  issn      = {0032-7786},
  pages     = {97 -- 112},
  year      = {2013},
  abstract  = {Plant species richness of permanent grasslands has often been found to be significantly associated with productivity. Concentrations of nutrients in biomass can give further insight into these productivity-plant species richness relationships, e.g. by reflecting land use or soil characteristics. However, the consistency of such relationships across different regions has rarely been taken into account, which might significantly compromise our potential for generalization. We recorded plant species richness and measured above-ground biomass and concentrations of nutrients in biomass in 295 grasslands in three regions in Germany that differ in soil and climatic conditions. Structural equation modelling revealed that nutrient concentrations were mostly indirectly associated with plant species richness via biomass production. However, negative associations between the concentrations of different nutrients and biomass and plant species richness differed considerably among regions. While in two regions, more than 40\% of the variation in plant species richness could be attributed to variation in biomass, K, P. and to some degree also N concentrations, in the third region only 15\% of the variation could be explained in this way. Generally, highest plant species richness was recorded in grasslands where N and P were co-limiting plant growth, in contrast to N or K (co-) limitation. But again, this pattern was not recorded in the third region. While for two regions land-use intensity and especially the application of fertilizers are suggested to be the main drivers causing the observed negative associations with productivity, in the third region the little variance accounted for, low species richness and weak relationships implied that former intensive grassland management, ongoing mineralization of peat and fluctuating water levels in fen grasslands have overruled effects of current land-use intensity and productivity. Finally, we conclude that regional replication is of major importance for studies seeking general insights into productivity-diversity relationships.},
  language  = {en}
}
@article{GrimmSeyfarthMihoubHenle2019,
  author    = {Grimm-Seyfarth, Annegret and Mihoub, Jean-Baptiste and Henle, Klaus},
  title     = {Functional traits determine the different effects of prey, predators, and climatic extremes on desert reptiles},
  series = {Ecosphere : the magazine of the International Ecology University},
  volume    = {10},
  journal   = {Ecosphere : the magazine of the International Ecology University},
  number    = {9},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {2150-8925},
  doi       = {10.1002/ecs2.2865},
  pages     = {17},
  year      = {2019},
  abstract  = {Terrestrial reptiles are particularly vulnerable to climate change. Their highest density and diversity can be found in hot drylands, ecosystems which demonstrate extreme climatic conditions. However, reptiles are not isolated systems but part of a large species assemblage with many trophic dependencies. While direct relations among climatic conditions, invertebrates, vegetation, or reptiles have already been explored, to our knowledge, species' responses to direct and indirect pathways of multiple climatic and biotic factors and their interactions have rarely been examined comprehensively. We investigated direct and indirect effects of climatic and biotic parameters on the individual (body condition) and population level (occupancy) of eight abundant lizard species with different functional traits in an arid Australian lizard community using a 30-yr multi-trophic monitoring study. We used structural equation modeling to disentangle single and interactive effects. We then assessed whether species could be grouped into functional groups according to their functional traits and their responses to different parameters. We found that lizard species differed strongly in how they responded to climatic and biotic factors. However, the factors to which they responded seemed to be determined by their functional traits. While responses on body condition were determined by habitat, activity time, and prey, responses on occupancy were determined by habitat specialization, body size, and longevity. Our findings highlight the importance of indirect pathways through climatic and biotic interactions, which should be included into predictive models to increase accuracy when predicting species' responses to climate change. Since one might never obtain all mechanistic pathways at the species level, we propose an approach of identifying relevant species traits that help grouping species into functional groups at different ecological levels, which could then be used for predictive modeling.},
  language  = {en}
}