Water Availability and Crop Growth at the Crop Plot Level in South Africa

This analysis considers the importance of water availability in crop growth at the crop plot level in South Africa. We focus on the four major grain producing provinces: Northwest, Mpumalanga, Free State and Gauteng. To this end we estimate the determinants of biomass production along the crop growing cycle using satellite derived measure of crop productivity every 16 days and spatially detailed crop field data which allow us to identify individual crop types. The results suggest a consistently important, but non-linear, effect of evapotranspiration within these regions. The role of other factors, such as irrigation, streamflow, proximity to rivers, and precipitation seem to depend to some extent on the crop type being considered.