Satellite

Biography

Biography: Essayas Kaba Ayana

Abstract

Sediment plumes to freshwater lakes and reservoirs decreases storage volume, reduces sunlight penetration in lake water and degrade the productivity of the whole food web in the aquatic system, reduces zooplankton growth and makes water supply disinfection costly. Intensive sampling of either sediment concentration or turbidity on many locations is prohibitively expensive. Techniques using remotely sensed images have become increasingly effective in estimating total suspended solid and turbidity in open water bodies. Nevertheless these techniques use relationships of remotely sensed reflectance and sediment concentration which are site specific. In this study calibrated coefficients from literature are used to establish a global relationship that relates TSS and reflectance measured by MODIS in one of the stream flowing into a fresh water lake. Site correction is applied to the established relationship and TSS time series is constructed for other four inflowing streams flowing and a major outflowing river, the Blue Nile. Out flowing TSS from remote sensing is validated using TSS samples taken at outlet of the lake. The TSS budget of the lake indicated that in a given season nearly 64% of the TSS accumulates in the lake.