Syn-B1 Current and future drivers of tree growth and forest dynamics: environment vs. tree functional strategies [funded by DFG]
PI(s) for this project:
Prof. Dr. Achim Bräuning
Dr. Jürgen Homeier
Prof. Dr. Wolfgang Wilcke
Abstract:
Tropical Andean forests are threatened by ongoing climate change, degradation and nutrient deposition, but extent and regional variation of these impacts on the biodiverse ecosystems are still poorly understood. For a predictive understanding, it is imperative to identify the processes (abiotic and biotic) that affect the distribution of species and thus influence the composition, functional diversity (FD) and ecosystem functioning of Andean forest ecosystems and, on the other hand, how species respond to changing environments. Interactions of trees with their environment have been studied on forest plots established in mountain rain forest (MRF) and the mountain dry forest (MDF) across gradients of elevation and climate within the RESPECT research unit. This project will use data from repeated MRF and MDF forest plot inventories (aboveground productivity, tree demographic rates) and above-and belowground functional trait data from more than 500 sampled tree species to deepen our understanding of the functional composition and stand dynamics of tropical tree communities along climate and soil gradients. A further aim is to improve the predictions of ecosystem target functions biomass production and water fluxes. We will quantify the relationships between abiotic conditions, trait variation of tree communities and their associated ecosystem functions, and test how stressful environments (less favorable climatic conditions, lower nutrient availability) reduce both functional FD of tree communities and their ecosystem functions. Work package (WP) 1 will focus on the distribution of tree functional types and patterns of FD in the study region, and WP2 will evaluate how forest dynamics (aboveground biomass and productivity) and tree demographic rates (recruitment and mortality) are related to abiotic drivers and tree FD. In WP3 we will use the results from WP1 & WP2 to test the effects of recent environmental change (with tree data from repeated forest plot surveys) and of future climate scenarios (using tree species subsets of the current species pool that will thrive under future climates) on functional composition and FD at the MRF and MDF study sites.
