Upscaling of vegetation dynamics in semi-arid landscapes under climate change

Köchy, M.

We use a cascading modelling approach to simulate vegetation dynamics along a climate gradient from Mediterranean to arid under climate change. The spatially explicit landscape model WADISCAPE with 1.5 km by 1.5 km resolution integrates results of a shrub model and an annuals model with finer resolution. Using two ICCP climate change scenarios (A2, B2) we generate projections of biomass production that can be used for grazing. These projections are used to estimate changes of the carrying capacity of small livestock. The decrease of herbaceous biomass (annual plants and shrub leaves) and carrying capacity with mean annual precipitation (MAP) was strongest in semi-arid climate, which therefore is most susceptible to a decrease of MAP. The temporal variability of the rainfall in the study region, however, is so great that the mean change of MAP does not result in significant changes of carrying capacity along the climate gradient.


1. General Meeting of the Canadian Society for Ecology and Evolution. 17.-20.5.2007 Toronto, Ontario (Canada)