Impacts of Land Use Land Cover Changes on Soil Loss in Madu Ganga Watershed Area During 2002 to 2022

Abstract

Soil erosion is one of the critical environmental and health issues faced by humans. Various natural and anthropogenic factors contribute to accelerate soil erosion, which in turn causes soil degradation. Land use land cover (LULC) changes in catchments is one of the major factors that contribute to man-made soil erosion. The prime aim of this study is to estimate the impact of LULC changes on total soil loss in the Madu Ganga estuary area between 2002-2022. Madu Ganga estuary is a highly urbanized area with large scale land use land cover alterations by human activities. Soil erosion modeling is helpful for predicting soil loss in highly urbanized landscapes. The Integrated Valuation of Ecosystem Services and Tradeoffs (InVEST) model is introduced by Stanford University for the valuation of ecosystem services and goods. Through this, InVEST Sediment Delivery Ratio (SDR) model is developed to assess sediment delivery into a watershed area. The Modeling approach was developed under the Geographic Information System (GIS) based environment for the past 20 years with 5-year intervals. Estimated mean total soil loss of the Madu Ganga watershed area for years 2002, 2007, 2012, 2017, and 2022 were 1.17, 1.61, 2.00, 6.56, and 6.61 t ha-1 year-1 respectively. Pearson correlation test was performed to build a relationship between vegetation cover and total soil loss in the area. The results of the analysis indicated a negative correlation (r= -0.014 p=0.778) between vegetation cover and total soil loss in the area. The findings of the study indicated that, during the past 20 years LULC changes have contributed to accelerate the soil loss of the area. Further the findings of the study emphasize the necessity of the implementation of LULC plans and policies to reduce soil loss in the watershed area.