福建省永定县的水土流失动态变化

目的]研究永定县近10a来水土流失动态变化,为该区后期进行水土流失的治理提供科学依据。方法]应用2000,2010年的Landsat TM影像数据,结合1∶10 000数字地形图对永定县的水土流失进行了动态监测研究。结果]永定县水土流失分布主要集中于东北部、东南部两大区域;水土流失强度主要以轻度侵蚀、中度侵蚀、强度侵蚀为主,极强烈、剧烈侵蚀只在区域内呈点状、少量分布;水土流失主要集中分布在300~800m的低山丘陵地带;近10a来,永定县水土流失呈现面积减小、侵蚀强度下降的趋势。结论]永定县水土流失范围较广,强度较大,治理时间长,因此近10a来的水土流失的动态变化在南方红壤区具有较强的代表性;目前该区水土流失严重的区域也是开发建设项目和人口活动密集的区域,因此应该加强对开发建设项目水土保持的监测和治理,减少人类活动对水土流失的影响。

Dynamic Changes of Soil and Water Loss in Yongding County of Fujian Province

Objective] The change research of soil and water loss in the previous 10 years in Yongding County of Fujian Province was expected to make scientific basis for the rehabilitation of soil erosion in the region.Methods] Landsat TM images of 2000 and 2010, combined with the 1DK]:10 000 digital topographic map of Yongding County were used for the dynamic monitoring research of soil and water loss.Results] The results showed that the soil and water loss in Yongding County mainly occurred in two main areas of northeast, southeast. In Yongding county, mild erosion, moderate erosion, and intensified erosion were mainly distributed. Very strong, intense erosion were sparsely distributed. Soil erosion is mainly distributed in low mountain foothills of 300~800 m. Over the past 10 years, a reducing trend with regard to the area and level was observed.Conclusion] Yongding County has the representative traits in southern red soil region of wide range of water loss and soil erosion, large harness strength, prolonged management. The serious soil erosion in that area are the outcome of overburdened development projects and human activities. Therefore the monitoring and management of soil and water loss in the course of projects development should be strengthened, and the influence of human activities should be reduced.