Environmental Impact Assessment (EIA) and Assessment of Soil Loss in Sandur Taluk due to Mining Activity in and Around Bellary District, South India

Abstract

The catchment boundary of Sandur Taluk covers an area about 1254.02 sq km. It is well known for repository of Iron and manganese ore mineralization, more than hundred mining companies were operated within the Sandur Taluk and majority of hillocks have undergone by mining activity. The Sandur Taluk is affected by excavation of Iron ore. An attempt is made to Environmental Impact Assessment (EIA) by attributing various parameters like Land Use Land cover, Soil, Geomorphology, and catchment boundary etc., The erosion is a natural geomorphic process occurring continually over the earth’s surface and it largely depends on topography, vegetation, soil and climatic variables and, therefore, exhibits pronounced spatial variability due to catchments heterogeneity and climatic variation. This problem can be circumvented by discrediting the catchments into approximately homogeneous sub-areas using Geographic Information System (GIS). Soil erosion assessment modeling was carried out based on the Revised Universal Soil Loss Equation (RUSLE). A set of factors are involved in RUSLE equation are A = Average annual soil loss (mt/ha/year), R = Rainfall erosivity factor (mt/ha/year), k = Soil erodibility factor, LS = Slope length factor, C = Crop cover management factor, P = Supporting conservation practice factor. These factors extracted from different surface features by analysis and brought in to raster format. The output depicts the amount of sediment rate from a particular grid in spatial domain and the pixel value of the outlet grid indicates the sediment yield at the outlet of the watershed.