片蚀与细沟间侵蚀过程中地表微地形的变化

CHANGE IN SURFACE MICRO-RELIEF DURING THE COURSE OF SHEET EROSIONAND INTER-RILL EROSION

采用室内人工模拟降雨和地统计分析相结合的方法,对4种人为管理措施地表微地形在片蚀和细沟间侵蚀过程中的变化特征进行了研究。结果表明,不同雨强下,各管理措施坡面地表微地形表现出了一定程度的不规则性。不同雨强和管理措施条件下,各等级的高程在片蚀阶段和细沟间侵蚀阶段都发生了相互转移;其中第Ⅰ级和第Ⅱ级转移出最多,且在细沟间侵蚀阶段后也只有很少部分转移至第Ⅰ级、第Ⅱ级;第Ⅲ级地表高程转移最少,且有大部分的其他等级的高程转入第Ⅲ级,这两个侵蚀阶段在0～0.01 m和0.01～0.03 m区域最易发生土壤堆积。

A study was carried out using the method of indoor simulated rainfall combined with geostatistical analysis to investigate characteristics of the change in surface micro-relief under four different kinds of management during the course of sheet erosion and inter-rill erosion.Results show that under the effect of rainfall,regardless of intensity,the surface micro-relieves of slopelands,regardless of management pattern,all demonstrated a certain extent of irregularity and inter-grade transfer in elevation in the process of sheet erosion and inter-rill erosion.GradeⅠand GradeⅡ were dominated with moving-out,and only a little was transferred back into Grade Ⅰand GradeⅡeven after the inter-rill erosion phase.Little elevation of the surface micro-relief of Grade Ⅲ moved out,but instead,most of the elevations of other grades moved into Grade Ⅲ,suggesting that in the regions between 0~0.01 m and 0.01~0.03 m deposition of silts occurs readily during the process of sheet erosion and inter-rill erosion.