Detection of Soil Erosion Potential Zones and Estimation of Soil Loss in Kushkarani River Basin of Eastern India

Abstract

Kushkarani river basin (172 Sq.km), a Chottonagpur plateau fringe river basin of Mayurakshi master stream. Most part of the basin is characterized by coarser lateritic soil with greater erodibility and high potentiality of erosion. Seasonal fluctuation of rainfall energized the process of weathering and generation of regolith. Present work thrusts on identification of soil erosion potential areas based on multi criteria decision approach. Seventeen parameters are employed in this work (i.e. drainage frequency, drainage frequency, soil type, hydraulic gradient, NDVI, ferrous mineral etc.) and weighted linear combination is used for extracting results. For estimating different potential    soil erosion zones Revised Universal Soil Loss Equation (RUSLE) is used. RUSLE is computed      using Arc GIS 9.3 and ERDAS Imagine 9.2 softwares. For validating these models, surface lowering rate measured by pegging operation and 107 sites of have been selected for      measured. From the analysis it is noticed that the region where soil erosion potentiality is very high, is also experienced high rate of soil erosion (>19 tons/ha./year) and upper catchment is highly    susceptible for erosion. Stream frequency, stream density, relatively steeper slope, coarser          soil texture, exposed land etc. are some of the major reasons behind such accelerated         erosion. Surface lowering measured from field also shows high lowering rate in the                 erosion susceptible region (>1.73 mm/year). These growing soil erosion especially fertile top soil loss is negatively impacted agriculture and sediment accretion within channels. People in most   part of the basin area depend on agriculture, so, soil loss issue is linked with livelihood challenges of them.