ORIGINAL ARTICLE Geospatial assessment of soil erosion vulnerability at watershed level in some sections of the Upper Subarnarekha river basin, Jharkhand, India Shuvabrata Chatterjee • A. P. Krishna • A. P. Sharma Received: 12 January 2012 / Accepted: 21 March 2013 Ó Springer-Verlag Berlin Heidelberg 2013 Abstract Undulating landscapes of Chhotanagpur pla- teau of the Indian state of Jharkhand suffer from soil ero- sion vulnerability of varying degrees. An investigation was undertaken in some sections of the Upper Subarnarekha River Basin falling within this state. An empirical equation known as Universal Soil Loss Equation (USLE) was uti- lized for estimating the soil loss. Analysis of remote sensing satellite data, digital elevation model (DEM) and geographical information system (GIS)–based geospatial approach together with USLE led to the soil erosion assessment. Erosion vulnerability assessment was per- formed by analyzing raster grids of topography acquired from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) Global DEM data. LANDSAT TM and ETM? satellite data of March 2001 and March 2011 were used for inferring the land use–land cover characteristics of the watershed for these years, respectively. USLE equation was computed within the GIS framework to derive annual soil erosion rates and also the areas with varying degrees of erosion vulnerability. Ero- sion vulnerability units thus identified covered five severity classes of erosion ranging from very low (0–5 ton ha -1 yr -1 ) to very severe ( [ 40 ton ha -1 yr -1 ). Results indi- cated an overall increase of erosion in the year 2011 as compared to the erosion computed for the year 2001. Maximum soil erosion rate during the year 2001 was found up to 40 ton ha -1 yr -1 , whereas this went up to 49.80 ton ha -1 yr -1 for the year 2011. Factors for the increase in overall erosion could be variation in rainfall, decrease in vegetation or protective land covers and most important but not limited to the increase in built-up or impervious areas as well. Keywords Watershed management  Soil erosion  USLE  Remote sensing  LULC change  Subarnarekha River Basin Introduction Watersheds are considered the basic units of resources and watershed management aims to rationalize the land and water resource use for optimal production with least adverse impacts to the natural resources (Sharma et al. 1998). Watershed management concept recognizes the linkages between uplands, low lands, land use, geomor- phology, slopes and soils (Mishra and Nagarajan 2010). In India, soil and water conservation are key issues behind demarcating the priority watersheds (Khan et al. 2001). A variety of landscapes exist with varying vul- nerability to erosion in the large watersheds like Subarnarekha within the Chhotanagpur plateau area of Jharkhand state in India (Krishna and Hemrom 2008). This river basin is highly dissected by the rivers and streams of varying dimensions. Erosion is a natural geo- morphic process that was active during the whole geo- logical time and formed the earth’s surface (Bathrellos and Skilodimou 2007). Soil is naturally removed by the action of water or wind and such occurrences of soil erosion have been taking place over the geological past. Soil erosion is an important characteristic signifying the natural physical processes, which is in effect within the watersheds. This is a gradual process that occurs when the S. Chatterjee (&)  A. P. Sharma CIFRI, Indian Council of Agricultural Research (ICAR), Kolkata, India e-mail: shuva01@gmail.com A. P. Krishna Department of Remote Sensing, Birla Institute of Technology (BIT), Mesra, Ranchi, India 123 Environ Earth Sci DOI 10.1007/s12665-013-2439-3