Land-use and Land Cover Change on Clay and Sand Mining: A Spatiotemporal Analysis in Ma-Oya Downstream in Sri Lanka

Mining is one of the main methods of extracting mineral resources. Due to mining potentially decreasing biodiversity, farmland, soil fertility, and contamination from mining waste may add additional stress on environmental quality and ecosystem services. The research was conducted to identify the loss of land and land-use changes due to clay and sand mining in the left Ma-Oya riverbank of the Katana Divisional Secretariat Division (KDSD). Geographically, environmentally, and socio-economically, the Ma-Oya River basin is one of the unique river basins in Sri Lanka. Due to sand and clay mining, the Ma-Oya River basin’s left and right riverbanks have been highly degraded during the last few decades. The study used the mixed method to identify the land use and land cover changes, especially the GIS and statistical techniques with quantitative and qualitative data. The study revealed that Ma-Oya left bank with significant modifications and land loss due to critical natural resource exploitation. Mainly clay has been excavated up to 835-meter distance from the left Riverbank of Ma-Oya, covering more than 60 hectares. According to the present value of lands in the area, it was the amount of Rs. 2,728,774,720 (27287 Rs/M). It is noted that there are four or five people lose their life annually due to drowning in these water holes. Moreover, the future prediction of land-use change has become a severe issue. Therefore, it is essential to involvement of government institutes to minimize the risk and establish sustainability.