黄土丘陵沟壑区水平梯田减沙作用研究  

Sediment reduction effect of level terrace in the hilly-gully region in the Loess Plateau

作　　者：刘晓燕[1] 王富贵[2] 杨胜天[3] 李晓宇[4] 马红斌[2] 何兴照[2] 

机构地区：[1]黄河水利委员会,河南郑州450003 [2]黄河上中游管理局,陕西西安710021 [3]北京师范大学,北京100875 [4]黄河水文水资源科学研究院,河南郑州450004

出　　处：《水利学报》2014年第7期793-800,共8页Journal of Hydraulic Engineering

基　　金：国家科技支撑计划课题(2012BAB02B05)

摘　　要：黄土高原水平梯田的减沙作用很可能一直被低估。本文分析了梯田对坡沟产水产沙的调控机制，认为水平梯田不仅可大幅减少自身产沙量，而且还可截留上方来沙，并通过减少坡面径流下沟实现沟谷减沙；有埂水平梯田对流域的减沙潜力可达65%~90%。基于黄土丘陵沟壑区第三和第五副区不同时期的实测数据，分析了多年平均降雨情况下不同规模水平梯田对流域的减沙作用；引入梯田比和减沙幅度的概念，构建了不同规模水平梯田与减沙幅度的关系式，可用于大空间尺度上水平梯田减沙作用的定量评价。分析认为，在梯田比5%~30%范围内，梯田比几乎与减沙幅度成正比；当梯田比大于35%~40%后，其减沙作用基本稳定在90%左右。水平梯田对洪水含沙量的削减作用不明显，对雨强的产沙响应不敏感。The sediment reduction effect of level terrace in the Loess Plateau is likely to have been underestimated before. By analyzing the water and sediment regulation mechanism of the terraces in the basin,it is realized that the level terrace can not only significantly reduce the sediment yield from itself, but also intercept the sediment yield from the upper area, and can achieve the valley sediment reduction by reducing runoff flowing from slope to valley. The sediment reduction potential of level terrace with ridges in watershed is up to 65%. Based on the measured data of the third and the fifth sub-district of the loess hilly region in different periods, the sediment reduction effect of different scale level terraces is analyzed under average annual rainfall condition. The concept of terrace ratio is introduced to build the relationship between terrace ratio and sediment reduction magnitude, which can be used to quantitatively evaluate sediment reduction effect of level terrace on a large spatial scale, When the terrace ratio is less than 30 %, the magnitude of sediment reduction is basically proportional to the terrace ratio;and when the terrace ratio is larger than 35%,the sediment reduction effect is basically stable at about 90%. The flood sediment concentration reduction effect of level terrace is not very obvious;this characteristic can be used to mea-sure the water-reducing effect of level terrace in the river basin.

关 键 词：黄土丘陵沟壑区 水平梯田 减沙作用 方法 

分 类 号：S157.3[农业科学—土壤学]