Soil Erosion Prediction Based on Land Use Changes (A Case in Neka Watershed)

Abstract

Problem statement: Land use change has transformed a vast part of the natural landscapes of the developing world for the last 50 years. Land is a fundamental factor of production and though much of the course of human history, it has been tightly coupled with economic growth. Soil erosion by water is one of the most important land degradation processes in the Mediterranean basins. The unplanned land use change within and near a fast growing agricultural land in Neka River Basin, led to an accelerated erosion of soil in the area. Approach: This study aims to find the relationships between land use pattern, erosion and the sediment yield in the study area. The land use coefficient (Xa) has applied in the model of Erosion Potential Method (EPM) to forecast the effect of the land type to reduce the erosion. Land cover and land use change was projected for the next decade using topography, geology, land use maps and remote sensing data of the study area. Results: The results of this study indicated that the total sediment yield of the study area has notably decreased to 89.24% after an appropriate land use/cover alteration. The estimated special erosion for the Southern Neka Basin is about 144465.1 m3 km-2 where after management policy is predicted 15542.9 m3 km-2 year?1, therefore the total difference for the study area has estimated about 128922.2 m3 km-2 year-1. Conclusion: The land use changes assessed among the different land cover classes. It is important to mention that conducting of the present study a very severe land cover changes taken place as the result of agricultural land development. These changes in land cover led to the forest degradation of the study area. Relationship between land-use changes and agricultural growth offered a more robust prediction of soil erosion in Neka watershed.