Spatial Distribution of Soil Erosion in A Black Soil Region of Northeast China Studied Using Remote Sensing and GIS Techniques

摘要

The soil erosion intensity and its spatial distribution ofMashezihe watershed located at Bin county in the typical gentlehilly black soil region of Northeast China Were studied using theSurface Erosion Grading Indicator (SEGI) method andUniversal Soil Loss Equation (USLE) model. Land cover typesand vegetation cover fraction derived from the Advanced LandObserving Satellite (ALOS) remotely sensed data were employedin conjunction with other spatial datasets (DEM and soil texture)for assessing soil erosion in the ArcGIS platform. Results showthat with the support of remotely sensed parameters by ALOS,the USLE model is able to identify more detailed information onsoil erosion than the SEGI method. The total areas of very slightand slight erosion identified by the two methods are very similar.However, the USLE model produced larger areas moderately,highly, and very highly eroded than the SEGI method. It alsoclassified severely eroded areas of 52.25hm2. According tograding regulation of soil loss tolerance issued by Ministry ofWater Resources of China, the areas of very slight erosion(namely no obvious erosion phenomenon) and slight erosionidentified by the USLE model are 21298.38 hm2 and 22919.19hm2, accounting for 45.49% and 48.95% of the entire watershed,respectively, mainly in areas with slopes smaller than 5° andelevations lower than 200 m. Areas moderately, highly and veryhighly eroded are 1776.75, 486.56 and 286.88 hm2, equivalent to3.79%, 1.04% and 0.61% of the study area, mainly in areas withslopes ranging from 8° and 15° and elevations ranging from 200to 300 m. The severely eroded areas are sporadically distributedin areas with slopes above 15° and elevations higher than 300 m.