Estimation of Soil Erosion and Sediment Yield on ONG Catchment, Odisha, India

Abstract

Soil erosion problem is one of the major problems in India. It is very difficult to estimate precise soil erosion for a particular period of time. Many experimental and theoretical methods have been derived for estimation of soil erosion on watershed basin. These methods involve Geographical Information System (GIS) which is used for the computation of sediment yield of Ong river basin Odisha, India. In this method spatial data of Ong catchment is disintegrated into homogenous grid cells to capture the catchment heterogeneity. The gross soil erosion in each cell was calculated using Universal Soil Loss Equation (USLE) by determining its various parameters. Here for the study of soil erosion, the Ong catchment at lower Mahanadi region is chosen as availability of gauged data at multiple locations within watershed area. The Ong catchment is having an area of 5128 km2 at the lower Mahanadi region in India. Using these maps, the gross soil erosion was routed to the watershed outlet using hydrological drainage paths, for derivation of transport capacity limited sediment outflow maps. These maps depict 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. By analysis of field data of ONG catchment with USLE method, the annual sediment yield of ONG catchment show good agreement with less than ±42% error. The highest sediment yield obtained at Salebhata gauging station which is equal to 24.3 ton/hect/year.