Remote sensing net primary productivity (NPP) estimation with the aid of GIS modelled shortwave radiation (SWR) in a Southern African Savanna

We tested whether and to what extent a remote sensing net primary productivity (NPP) estimation model based on the moderate resolution imaging spectroradiometer (MODIS) data and GIS modelled shortwave radiation can be used to estimate NPP in a Southern African Savanna landscape. To accomplish this, we compared the results of our model with results obtained using an established rainfall-NPP regression model developed by Lieth and Whittaker (1975) for the savanna landscape, as well as the dry matter productivity (DMP) remotely sensed model. Results show that our model estimates do not significantly (p > 0.05) differ with results from the Lieth regression model with an R2 of 0.67. In addition, results showed that our remotely sensed NPP correlated significantly (p < 0.05) with the DMP results (Pearson Correlation R = 0.91). These results suggest that we can successfully model African Savanna NPP using MODIS remotely sensed data in combination with GIS modelled clear sky and topographically based shortwave radiation (SWR) flux.