The degradation scenario of man-made lakes from satellite observations: A case of Wadi El-Rayan lakes, Egypt

Abstract

The environmental changes in the wetlands are one of the major problems facing us in recent decades. Lately, many fluctuations have been observed in Wadi El-Rayan lakes. The geo-spatial analysis plays a great role in detecting the changes in Wadi El-Rayan lakes. The aim of the current study is to enrich the knowledge about Wadi El-Rayan Depression and to identify the changes in its lakes (Upper Lake and Lower Lake) and land cover by integration between RS and GIS techniques. The Upper Lake has become completely full with relative stability in its water area of around 53.61 (±2%) million m², but the Lower Lake is markedly decreasing by 1.92 million m² per year. It should be noted that it is hard to manage those artificial lakes because of human activities. These activities include reusing drainage water, land reclamation, and rapidly expanding aquaculture. Therefore, the optimum solution to this problem is to adjust water allocation within Wadi El-Rayan lakes by reducing the amount of water diverted for reuse, agriculture, and fish farms, or at least resecting the growth in these water uses to help stop or slow the decrease in Wadi El-Rayan lakes.