The objective of this study is to investigate potential effects of
reduced precipitation on tropical forests in Madagascar using a
local forest model (stand-level model). The FORMIX3 model (Huth
and Ditzer, 2000; Huth et al., 1998), which is applied in this study,
combines the forest gap model approach with the calculation of
tree growth based on a carbon balance approach. In this study, the
individual-based forest model has been extended by incorporating
a water cycle module, which is a precondition to analyse the effect
of reduced precipitation on forest structure in a mechanistic
manner. We especially focus on the question how reduced annual
rainfall and soil water deficit affect aboveground biomass, primary
production, carbon pools and net ecosystem exchange (NEE) in a
tropical forest in Madagascar. In this way, we want to evaluate the
robustness of forest dynamics and carbon cycling against changes