Monitoring Water Quality and Land Cover Changes In Lake Victoria&Wetland Ecosystems Using Earth Observation

Use of remote sensing in assessing water quality has expanded due to increased scanning of water bodies within a short time. The main parameters examined in this study are chlorophyll concentration, water turbidity due to erosion and water pollution as well as total suspended materials (TSM). All these cause changes in the color of the water bodies on the various wave lengthens of the electromagnetic spectrum. Assessing regional water quality is necessary but limited by scarcity of data. In this study, we have compared land cover changes and resulting water quality of Lake Victoria and relationship of resulting water quality due to changes within wetlands. We did mapping to provide ability to identify turbid and clear water with focus of producing water quality and substrate land cover type maps after comparison of Landsat and MERIS images. We also analyzed vegetation health over the period by comparing the NDVI results over the periods selected for investigation. We have compared the changes in land cover as well as destruction of wetlands and established that there is positive correlation of destruction of land cover and resulting poor water quality. It has been demonstrated that remote sensing is useful technique in mapping spatial distribution parameters such chlorophyll. The algorithm used on BEAM Visat has provided useful information that additional parameters are used to estimate suspended sediment concentration (SSC) through extraction of open water covered areas. Results of the analysis have shown that chlorophyll concentration on Lake Victoria increased over time from the year 2002 to year 2013. For instance between year 2002 and 2007, the Chlorophyll concentration has increased from 37.41 to 40.8 mg m^3 representing 9.16 % increase in chlorophyll concentration within the lake.