Erosion and Sediment Yield Modeling with USLE, Arc GIS and SWAT

Abstract

The economy of most of the people in India is mainly based on rain fed agriculture. The
agriculture yield primarily depends on the availability of good productive soil and sufficient
quantity of availability of water. In the past, in many areas both were available but recently it
is observed that due to various abnormal natural processes and excessive human interference
in the natural processes, the soil layer with nutrient from fertile land is getting eroded, which
resulted into reduced fertility and reduced crop yield. The soil loss from the catchment directly
and indirectly affects the living standard resulting into various social problems. In order to take
the preventive and curative measures against this soil erosion, it is necessary to estimate the
quantity of the soil eroded and the major causes for the erosion. The soil erosion for the study
area is estimated with a good degree of accuracy by integrating Geographical Information
System technique and Universal Soil Loss Equation (USLE) with supportive Soil and Water
Assessment Tool. In USLE model the soil loss is estimated using the parameters like rainfall
erosivity (R), soil erodibility (K), slope length-steepness (LS), cover management (C) and
conservation practice factor (P). The average annual soil loss estimated for the study area by
QSWAT technique is 72.42 ton ha-1 year-1and using arc GIS soil loss estimated is 67.87 ton ha-1 year-1. The spatial distribution of USLE parameter indicates mild and moderate risk due to soil erosion in the study area.

Keywords: USLE, arc GIS 10.2.2, QSWAT, Erosion, Thematic