Erosion susceptibility zoning and prioritization of miniwatersheds using Geomatics approach

Sediment yield data is generally not available for smaller hydrologic units and it becomes difficult to identify the most vulnerable erosion zonethat can be treated on a priority basis. The study area is 163407 ha lies between 23° 13′ 12"N 23° 33′ 1′′ N latitude and 85° 10′ 28′′ E 85° 54′ 16′′ E longitude having 3870 streams linked with 7 order of streams and divided in to 20 miniwatersheds. The evaluation of morphometric and Universal Soil Loss Equation (USLE) parameters using remote sensing and GIS for prioritization of miniwatersheds in Subranerakha Subcatchment, Jharkhand, India. Furthermore, attempt was also made to compare the ranks obtained from both parameters to ascertain the validity of ranks of USLE. The ranks of USLE were found more appropriate and are considered for the prioritization of miniwatersheds. Five categories of priority viz., very high, high, medium, low and very low, were used to classify the miniwatersheds. The prioritization results reveal that four miniwatersheds viz. USR7, USR8, USR10 and USR5 fall under the category of very high priority. The area is grouped in to very severe, moderately severe, moderate, slight and very slight erosion susceptibility zones. GIS and remote sensing based evaluation of morphometric and USLE parameters for ranking them is an immense help in the prioritization of small hydrologic units. Further the technology is helpful in erosion susceptibility zone mapping based on ranks obtained from morphometric and USLE parameters for evaluation of conservation measures for ridge to valley treatment.