Spatiotemporal analysis of landscape patterns and its effect on soil loss in the Rmel river basin, Tunisia

Abstract

Changes in land use and land cover (LULC) are generally associated with environment pollution and the degradation of natural resources. Detecting LULC changes is essential to assess the impact on ecosystem services. The current research studies the impact of the LULC change on the soil loss and sediment export in a period of 43 years from 1972 to 2015. Landsat imageries were classified into five classes using a supervised classification method and the maximum likelihood Algorithm. Then, the sediment retention service for avoiding reservoir sedimentation was assessed using the InVEST SDR (integrated valuation of ecosystem services and trade-offs sediment delivery ratio) model. The results showed that the changes are very important in this study period (1972–2015). Forests were reduced by 18.72% and croplands were increased by approximately 54%. The InVEST SDR model simulation results reveal an increase in the sediment export and soil loss, respectively, from 1.68 to 5.57 t/ha/year and from 15.22 to 43.61 t/ha/year from the year 1972 to 2015. These results highlight the need for targeted policies on integrated land and water resource management. Then, it is important to improve the common understanding of land use and land cover dynamics to the different stakeholders. All these can help in projecting future changes in the LULC and to investigate more appropriate policy interventions for achieving better land and water management.