Impact of Land Use/Land Cover Change on Soil Retention Service: A Case of Agricultural-Urbanized Landscape in Northern Iran

Abstract

Globally, urbanization changes land use/land cover (LULC) and alters ecosystem functions and services. Soil retention (SR) is a critical ecological service that is strongly related to LULC change. The topic of this study is assessment of LULC change on soil retention service (SRS) in a fragile seminatural-urbanized landscape of the Jajrood basin in Northern Tehran, Iran, from 2000 to 2020. To achieve the goal, the LULC maps and the other relevant datasets were imported into the Integrated Valuation of Ecosystem Services and Trade-offs tool (InVEST) using the Universal Soil Loss Equation (USLE). Calibration and validation were performed using Goodness-of-fit test for observational and modeled data. The results revealed that LULC change had both negative and positive effects on SR. The built-up area increased dramatically by about 133 percent, while the rangeland shrunk by approximately 5 % during the twenty-year, leading to an increase in soil erosion and reducing SR. On the other hand, the agricultural and gardening activities expanded by 41 %, which caused an increment in SR. Due to the outgrowth of man-made areas compared to the other land uses, the overall SR decreased by about 17,000 tons. Moreover, the result indicated that slope, elevation, and land management factors, respectively, had the highest correlation with SRS. The finding of this research can provide insight to land use planners to protect the areas with high soil erosion.