Hydrologie: Aktuelle Forschung

Analysis of Monthly and Seasonal Groundwater Fluctuations in Zimbabwe: A Remote Sensing Perspective

Abstract

David Chikodzi

The main aim of the research was to produce seasonal and yearly groundwater fluctuations in catchments around Zimbabwe from a remote sensing perspective so as to identify patterns of groundwater depletion and recharge. This information is vital so as to ensure that groundwater development in Zimbabwe proceeds in parallel with the effective evaluation and management of the resource. In Zimbabwe, measurement, monitoring and analysis of groundwater levels is limited and completely absent in some areas because of the costs involved. The research used monthly GRACE satellite data from 2004-2010 with a spatial resolution of 20*20 kilometres. The data was imported into a
Geographical Information System, interpolated using the moving average method and then statistically analysed to show average monthly fluctuations and average yearly fluctuation patterns in catchments around Zimbabwe. The results showed that the average groundwater levels in Zimbabwe are about 0.92 cm above the long term mean level and have a declining trend line. The results show that the average monthly and seasonal groundwater levels in Zimbabwe are declining with more seasons and months recording below average levels. The study also produced a new method of rapid assessment of groundwater resources which is also considerably cheap.