Assessing The Immediate Impact Of Surrounding Land Uses On The Extents Of Freshwater Body Over Time In Madagascar - A Demonstrative Case Study Of Itasy Lake -

Unplanned land use conversion driven by increasing food demand has threatened rich forest resources and freshwater fishery resources in Madagascar as a result of increasing sedimentation. For sustainable use of freshwater fishery resources, it is important to examine the impact of land use changes on sedimentation. Severe sedimentation often fills-in and shrinks lakes. Also, sedimentation causes lakebeds to rise, which can lead to flooding and therefore affect the position of the lake's boundary, over time. Recently available historical satellite images can be useful in assessing the changes in the position of lake boundaries over time. In this study, we propose a modeling approach for evaluating the impact of surrounding land uses on the extents of Lake Itasy, in Madagascar. In order to demonstrate our approach, we utilized satellite imagery available via Google earth to obtain a historical snapshot of the lake boundary. We delineated it and combined the results with a land use map. We then conducted a simple spatial statistics analysis using a logistic regression model with time varying coefficients. Our approach quantifies the impact of surrounding land uses on varying positions of lake boundaries over time.