基于3S技术和USLE的深圳市茜坑水库流域土壤侵蚀强度预测研究

Soil Erosion Intensity Prediction Based on 3S Technology and the USLE: A Case from Qiankeng Reservoir Basin in Shenzhen

基于RS、GPS和GIS(3S技术)的集成提出了USLE 6大因子的算法,在建立的专题地理信息数据库基础上,运用USLE对深圳市茜坑水库流域的土壤侵蚀强度进行预测和估算.结果表明:整个流域90.5%的区域土壤流失强度为中度以下,强度侵蚀以上的区域虽然仅占整个流域面积的9.5%,但是年土壤侵蚀量达到了整个流域土壤侵蚀量的49.4%.流域土壤侵蚀强度和植被覆盖情况明显相关,茜坑水库流域的东北山区部分是整个流域的严重侵蚀区.研究证明:在3S技术集成支持下,采用USLE对流域的土壤流失强度进行预测和估算的方法具有直观、方便、快捷的优点,成果能充分满足小流域水土保持工作的需要.

Based on the integration GIS, RS and GPS technologies, and on a geodatahase with respect to basin, proper methods were introduced to obtain the values of R. LS. K, Cand P factors in the Universal Soil Loss Equation （USLE）. Then, taking the Qinkeng Reservoir basin in Shenzhen as an example, the soil erosion wherein was predicted using USLE model. The study showed that slightly eroded area and medium eroded area together occupied 90.4% of the total watershed area. wit h the rest 9. 6% occupied by the serious and extremely serious eroded area. However, the later had contributed 49.4% to the total annual soil erosion. The result also indicated that the soil erosion of Qiankeng Reservoir basin had an obvious correlation with the C factor value which represented the crop management factor, and the most serious soil eroded place was located in the northeast mountain area. As a whole, the study has proven the USLE model bascd on the 3S technologies would providea simple, easy and accurate approach to predict soil erosion.