Biodiversity dynamics and ecological cascading in logged tropical forests of the Guiana Shield - Consequences and perspectives for amphibian communities in anthropogenically altered ecosystems

• Applicant: Dr. Raffael Ernst
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions
• Term: from 2009 to 2013
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 117165681

Conventional views of the biodiversity-ecosystem-functioning debate such as the diversitystability/- instability paradigms have seriously been challenged in recent studies. It has been acknowledged that the relationship between diversity and any stability property may be different for different variables and conditions. Hence, resulting community patterns potentially depend on the respective diversity scale (e.g. species diversity vs. functional diversity) and historical factors such as disturbance history and phylogenetic history. In this project I aim at resolving interactions between different levels of biodiversity and ecosystem functioning in complex tropical forest ecosystems under the influence of human induced disturbance (timber harvesting) using amphibian communities as organismic model system. The proposed project is unique in that it will closely be linked to a strictly controlled timber harvesting scheme implemented by my project partner Iwokrama International Centre for Rainforest Conservation and Development under the auspices of Forest Stewardship Council (FSC). This will put me in the exceptionally rare position to conduct true pre-and post impact studies that allow linking impacts, effects and underlying processes at the ecosystem functioning level in a direct manner. I will test a set of hypotheses related to diversity pattern changes at the species, community, phylogenetic, functional and trophic level and particularly address yet unresolved questions such as the redundancy-insurance problem of community ecology theory and the problem of ecological cascading following disturbances in natural systems. Analysis of trophic structure will provide direct links to ecosystem functioning. The ultimate goal will be the development of predictive models of ecosystem dynamics and potential decay following anthropogenic disturbances and the identification of predictors (e.g. functional traits) of species’ extinction sensitivity to these disturbances. This is a novel approach not yet taken in the analysis of diverse vertebrate communities in the tropics.

• DFG Programme: Research Grants