The role of indirect interactions via shared pollinators in shaping grassland communities along productivity gradients

• Applicant: Professorin Merav Seifan, Ph.D.
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: from 2010 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 188218979

Many grassland plant species depend on generalist pollinators for reproduction. Therefore, their fitness depends not only on their own traits (e.g. attractiveness) but also their neighbor's traits. Such indirect effects range from negative to positive, i.e. neighbor presence may decrease or increase the number of visiting pollinators. Because of the different spatial scale of pollinator decisions, neighbor effects may also change with species density and spatial pattern. Surprisingly, little is known about shared pollination effects and the conditions governing them. In particular, there is no integration of shared pollination effects with general theory of community ecology. Here, we intend to fill this gap by combining field and garden experiments with simulation models. We focus on the following hypotheses:- Plant density, spatial pattern and relative attractiveness critically affect the outcome of shared pollination services.- The role of shared pollination in shaping plant interactions and community diversity depends on habitat productivity. While productivity often negatively covaries with direct positive interactions, we suggest a unimodal response of indirect interactions to productivity.As a case study we use grasslands along a natural productivity gradient. The results will be important for understanding of the mechanisms shaping plant communities, but also for nature conservation and landscape management.

• DFG Programme: Research Grants
• Participating Person: Professorin Dr. Katja Tielbörger