A framework for risk assessment on soil erosion by water using an integrated and systematic approach

A new approach for establishment of an analytical risk assessment model to evaluate the risk index for soil erosion by water is proposed, in which the remote sensing, GIS, the analytical hierarchy process (AHIP), and modeling techniques are integrated through investigation of soil erosion by water in a joining area that partially covers the Shanxi province, Shaanxi province, and Inner Mongolia Autonomous Region of China. Based on field survey and information analyses, pertinent factors for soil erosion by water in this region are assessed and nine dominating factors are identified. The considered dominating factors include the soil. type, rainstorm intensity, landform accounting for physiognomy type, ravine density, and land slope, vegetation coverage, mining area, level of water and soil conservation, and type of Land uses. The GIS thematic layers of degrees of risk on soil. erosion for those dominating factors are constructed. The weight of each thematic layer is determined through the AHP technique. This model is then applied in predicting development of soil. erosion at a typical scenario for this study area. A brief discussion on construction and application of this model. is presented. It is demonstrated that the presented methodology is practicable for establishing a risk assessment mode for soil. erosion by water for an area of interest where pertinent information such as remote sensing data is available. A flowchart presenting a general procedure for implementation of the proposed approach is also included. (c) 2007 Elsevier B.V. All rights reserved.