降雨条件下地表糙度对片蚀的影响及其变化  

Effects of soil surface roughness on sheet erosion and change under different rainfall conditions

作　　者：郑子成[1,2,3] 何淑勤[4] 吴发启[2] 

机构地区：[1]四川农业大学资源环境学院,雅安625014 [2]西北农林科技大学资源环境学院,杨凌712100 [3]北京师范大学地表过程与资源生态国家重点实验室,北京100875 [4]四川农业大学林学院,雅安625014

出　　处：《农业工程学报》2010年第S1期139-145,共7页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(40901138);国家重点基础研究发展计划(2007CB407201);中国科学院山地灾害与地表过程重点实验室开放研究基金资助项目;地表过程与资源生态国家重点实验室开放基金资助项目(2008-KF-05);四川省科技厅资助项目(2008JY0022)

摘　　要：为了进一步明确地表糙度在片蚀过程中的效应,该文通过室内人工模拟降雨的方法,就场降雨和连续降雨条件下,地表糙度对片蚀的影响及其变化进行了研究。结果表明,场降雨条件下,实施人为管理措施坡面的径流与产沙量均低于对照坡面;在雨强0.67mm/min条件下,随地表糙度的增加,径流量与侵蚀量呈先减小、后趋于稳定的变化趋势;而在雨强1.63mm/min条件下,随地表糙度的增加,径流量与产沙量却呈一直减小的变化趋势。在雨强0.67mm/min条件下,耙耱地、人工掏挖和等高耕作坡面的地表糙度均呈减小的变化趋势,而人工锄耕坡面的地表糙度呈增加的变化趋势;在雨强1.63mm/min条件下,人工掏挖和等高耕作坡面的地表糙度呈减小的变化趋势,人工锄耕、耙耱地坡面的地表糙度却呈增加的变化趋势;对照坡面地表糙度的变化,与耙耱地相反。连续降雨条件下,在前二次降雨作用下,坡面的径流量与产沙量随地表糙度的增加而逐渐减小,且均低于对照坡面;在第三次降雨条件下,径流与侵蚀产沙量变化较为复杂,且实施人为管理措施坡面均高于对照坡面。不同降雨条件下,实施人为管理措施坡面地表糙度对片蚀具有一定的抑制效应,且坡面片蚀的发展与地表糙度间的变化表现出相应的互动作用。该文研究结果为揭示地表糙度的侵蚀特征提供了一定的理论依据,同时也为黄土高原坡耕地的水土流失治理奠定理论基础。To further determine the effects of soil surface roughness on sheet erosion, changes of soil surface roughness were obtained under the single and continuous rainfall intensities based on the artificial rainfall simulation experiments. The results showed that under the rainfall intensity of 0.67 mm/min, the runoff amount and sediment yield of each slope decreased firstly, and then the stable change with the increasing soil surface roughness. Soil surface roughness declined for other artificial management practices except for hoeing cropland, opposite to the changes of contrast slope. Under the rainfall intensity of 1.63 mm/min, the runoff amount and sediment yield of each slope decreased with the increasing soil surface roughness. Soil surface roughness decreased for the slope of digging cropland and contour tillage, consistent to the changes of contrast slope. While soil surface roughness increased for the slope of hoeing cropland and raking cropland, opposite to the changes of contrast slope. Under the continuous rainfall intensity, the runoff amount and sediment yield of artificial management practices decreased gradually with the increasing soil surface roughness, and were lower than those of the contrast slope at the first and second rainfall. The changes of runoff amount and sediment yield were comparatively complex, and sediment yields of the slope with artificial management practices were higher than those of contrast slope at the third rainfall. The results will provide theory basis for posing the erosion nature of roughness, and at the same time, it will serve for harnessing soil and water loss of the slope farmland in Loess Plateau.

关 键 词：降雨 侵蚀 糙度测量 片蚀 场降雨 连续降雨 

分 类 号：S157.1[农业科学—土壤学]