Geographic variation in the impacts of land use changes on ecosystem stability
Biomass production by woody plants is critical for the services provided by forest ecosystems, but it is increasingly threatened by climate change, land use and insect herbivory. Current theory predicts that biodiversity can buffer against this loss of ecosystem services by maintaining the stability (characterized by the resistance, the resilience and the invariability) of ecological communities. However, empirical evidence remains controversial, especially because most of the existing data has been obtained from studies that have addressed diversity stability relationships on small spatial scales. The fundamental objectives of the research proposed here are to verify the importance of biodiversity in maintaining the stability of ecosystem functions and to explore geographical variations in the impacts of land use on the stability of trophic interactions in forest ecosystems. We will use the invariability of resource consumer interactions as a measure of ecosystem stability. By analyzing the temporal variability in the losses of woody plant biomass to leaf and root-feeding insects and in the predation rates by birds on these insects in differently managed ecosystems across major terrestrial biomes, we will test whether mechanisms underlying the stability of trophic interactions are consistent across the globe. Ultimately, we will identify the factors that affect ecosystem stability and the regions where natural and managed ecosystems are most vulnerable to ongoing environmental changes. This information will be used to improve predictions of the consequences of rapid environmental changes on forest ecosystems at the global scale and to develop evidence-based management strategies for conservation of biodiversity and for mitigation of the impacts of biodiversity loss on the provision of ecosystem services. In addition, by establishing new multilateral cooperation and by stimulating the mobility of the project participants, we will enhance the research and innovation capacity and integration of knowledge across Latin America and Europe.