An assessment of rainfall-induced land degradation condition using Erosivity Density (ED) and heatmap method for Urmodi River watershed of Maharashtra, India

Abstract

Soil erosion caused by rainfall is a serious issue in hilly terrain areas. Rainfall creates erosivity impact on soil; this force can be calculated using R-factor of Revised Universal Soil Loss Equation (RUSLE). For assessment of rainfall impact at Urmodi River watershed (Maharashtra, India), data of six weather stations were used of 22 years, from 1991–2013. Using the same data rainfall pattern map, R-factor map was plotted. The ratio of R-factor of RUSLE to annual rainfall gives us the erosivity density (ED). All maps are prepared using Inverse Distance Weighted (IDW) method of interpolation. Along with the maps, the precipitation pattern at each weather station was plotted using heatmap. The average rainfall value in the watershed was found to be 1247.13 mm/year. The mean R-factor at Urmodi River watershed was 531.69 MJ mm ha−1 h−1 year−1. Whereas, mean ED value at whole catchment level shows 0.42 MJ ha−1 h−1. At the upper catchment of the study area, there located ‘Kaas Plateau’ which is a world heritage site. As the region is an eco-sensitive area, this study makes possible to assess the impact of rainfall and predict soil loss. This information is important because it allows to adapt the soil protection measures.