Tropical Vegetation

12 October 2015

Early versions of SWAT did a poor job of simulating the leaf area dynamics of perennial tropical vegetation like forests and savannas in which drought rather than cold temperatures triggers annual leaf senescence and the onset of the rainy season stimulates their regrowth. For his work in Brazil, Michael Strauch (michael.strauch@ufz.de) developed algorithms to address this issue. It requires the user to input the beginning and ending months of the transition period at the end of the dry season when plant growth is expected to resume, as well as the soil moisture content that triggers regrowth. Functioning only at latitudes between 20ºN and 20ºS, the algorithm causes leaf area index to fluctuate realistically between the minimum and maximum LAI of the vegetation type. This improvement has recently been incorporated into SWAT2012 and SWAT+. For more information contact Dr. Strauch.