Integrating Geoinformatics and Remote Sensing Data to Assess Impacts of Flooding on Land Productivity in the Zambezi River Floodplains, Namibia

Abstract

Exposure to flood waters poses a risk to land productivity and livelihoods of communities in the Zambezi River Basin who are engaged in arable agricultural activities along its floodplains. This is exacerbated by occurrence of frequent flooding events in the area since 2008 due to climate variability. The objective of this research is to assess the extent of exposure to flooding on floodplain land used for maize production along the Zambezi River in Namibia. Existing survey information on geospatial locations of farms is used as baseline data. Field survey maps are then overlaid into flood maps developed using 2013 Landsat satellite data taken during peak flood event, and DEM. Weighted sum overlay results show that 14.5% of croplands were inundated with floods by March 2013. Integration of inundation results into a DEM show areas at low, medium and high risk to flooding. This provides useful geospatial information for flood mitigation.