Effects of changed hydrological conditions, especially waterlogging, on biotic interactions in grassland

Under climate change, not only temperature, but also rainfall conditions are changing. For Central Europe, rainfall is predicted to become more variable, with longer dry spells, but also more extreme wet episodes. In this project, we investigate how changes in soil moisture conditions, ranging from very dry to waterlogged, affect biotic interactions and soil processes in grassland. We assess how plant-plant interactions might change along the stress gradient, how flower phenology, nectar quantity and quality as well as pollinator visitations are affected and whether herbivores amplify effects of hydrological condition and are in turn affected by changing soil moisture. We further quantify soil nutrients and mycorrhization rates. The results of this project will help in estimating potential consequences of climate change for grassland species, and will moreover help to answer fundamental questions on species niches and the role of competition and facilitation along stress gradients