Uni-Bayreuth grafik-uni-bayreuth



Ecophysiology of climate change- effects of extreme drought on leaf fluorescence parameters and protein content in heath- and grassland communities (EVENT experiment)

Julia Walter1, Uwe Rascher2, Nico Blüthgen3, Maik Veste4, Martin Schädler5, Anke Jentsch6, Carl Beierkuhnlein7
1 Helmholtz Centre for Environmental Research- UFZ, Leipzig
2 FZ Jülich, ICG-III
3 University of Würzburg, Departement of Animal Ecology and Tropical Biology
4 BTU Cottbus
5 University of Magdeburg; Departement Animal Ecology
6 Helmholtz Centre for Environmental Research- UFZ, Leipzig and University of Bayreuth
7 University of Bayreuth; Departement Biogeography

O 4.5 in Climate change research

02.04.2009, 17:15-17:30, H8

Water availability is a major limiting factor for plant productivity in ecosystems. The frequency of drought events is likely to increase in the near future due to climate change. While many studies in climate change research focus on changes in plant productivity due to temperature or CO2 increase, our research interest particularly includes 1) manipulation of extreme weather events and 2) analysis of underlying physiological mechanisms in plant response, such as the role of photosynthesis in productivity and metabolite content and herbivory. Photosynthetic capacity is seen as crucial bottleneck in plant primary productivity. Plant stress, e.g. affecting protein content and amino acid composition is seen as driving factor of insect feeding behaviour. Here, we examine: 1) Species-specific response of photosynthetic parameters to water stress, assuming that functional resilience and recovery of physiological performance varies by species. 2) Individual response of photosynthesis to water deficit as a function of community composition. 3) Individual response of plant protein content and amino acid metabolism to water stress as a function of community composition directly affecting plant-herbivore interaction. The investigated species showed clearly different patterns of stress response and stress level. Ecophysiological parameters of Holcus lanatus were strongly modified by community composition, showing lower maximum quantum yield and water potential in communities including a legume. Protein content of Holcus lanatus was lowered under stress and also modified by community composition. It was higher in communities including a legume or consisting of only two species than in communities consisting of four species.

last modified 2009-03-08