How does rainfall effect tree and grass growth?
A report on rainfall manipulation experiments in the Kruger National Park, South Africa. Rademan, Louise*,1, Bond, William1, February, Edmund1, Higgins, Steve2, 1 Department of Botany, Cape Town, South Africa2 Chair of Vegetation Ecology, Munich, Germany ABSTRACT- The mechanisms behind the co-existence of trees and grasses are a central question in savanna ecology. Our research, based in the Kruger National Park, South Africa, aims to evaluate hypotheses that explain grass -tree co-existence. Medium-term rainfall and competition experiments replicated across a soil template and rainfall gradient have been set up using rain-out shelters and irrigation plots. Data on above ground tree and grass biomass production and below ground changes in soil moisture have been recorded for two growing seasons. The data show a decrease in grass standing crop with a decrease in rainfall amount at both sites but an increase in standing crop with an increase in rainfall at the high rainfall site. Manipul
