Utilizing remote sensing and GIS to characterize watersheds and evaluate soil loss in Dehradun, Garhwal Himalaya

Abstract

The most crucial aspect of watershed management is watershed characterization, which includes soil loss. Soil loss assessment uses geospatial tools like remote sensing and GIS to show the amount of soil loss or erosion in tons per hectare per year. Both natural and man-made factors contribute to the loss of agricultural land, whereas human factors hasten soil erosion. It is a global phenomena that results in decreased plant water table availability, increased runoff from the more impermeable subsoil, and soil nutrient loss. Planning and batter management in a watershed and planning units benefit most from watershed management and soil loss assessment. The satellite image-based model technique combined with remote sensing and GIS provides a scientific, quantitative, and useful outcome. Under all climatic conditions, it can calculate a consistent result of soil erosion and sediment yield for a variety of locations. The Tons watershed, which spans 97.02 km2 (9,702 hectares) under the sub-tropical climate region of Uttarakhand, is located between 77°56’05" E to 78°01’01" East longitude and 30° 21’05" N to 30°26’51" North latitude. The Revised Universal Soil Loss Equation (RUSLE) applies to soil loss and GIS. A = is the calculated soil loss per unit area, R = is the rainfall erosivity, K = is the soil erodibility factor, L = is the slope-length factor, C = is the cover and management factor, and P = is the support practice factor. These are the results of the current case study, which is based on computational software and geospatial technologies. Rainfall erosivity (R=87.5 + 0.375 × R), C P is within the range of 0.006-0.8, and the range of soil erosion risk is between 51.40% and 0.85% for the whole research region. In 2016, the open woodland had the largest soil loss (56.58 tons/ha/year) and the riverbed had the lowest (0.17 tons/ha/year) according to several land-use classifications. Part of the research region falls into a moderate and moderate-high zone, while the remainder falls into a low likelihood zone. The case study is highly recommended and will aid in the adoption of soil conservation and loss control practices in the Himalayan areas and the Tons watershed.