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浅沟侵蚀是黄土区坡面侵蚀重要的侵蚀类型,通过模拟试验发现了浅沟侵蚀形态发育过程中宽深比的变化规律及其水流流态特性。结果表明:浅沟沟槽侵蚀发育重要参数宽深比的变化规律与是否进行耕作处理关系密切,随着侵蚀的进行其宽深比逐渐减小,并且稳定在1左右;浅沟水流属于紊流,其雷诺数随着坡度和雨强的增大而增大。耕作和汇水面积的增大造成雷诺数的波动范围变大;浅沟水流在急流和缓流之间不断转换。相同条件下,耕作使得浅沟水流的弗汝德数Fr值变小,且随着雨强和坡度的增大,耕作对弗汝德数的影响越来越小。研究结论对完善黄土区坡面侵蚀研究具有重要意义。
Slope erosion is an important type of erosion on slope erosion in loess area. The variation law of width-to-depth ratio and its fluid-flow characteristics are found through the simulation test. The results show that the variation law of broad-deep ratio, which is an important parameter for the development of shallow trench trench erosion, is closely related to whether the tillage process is carried out or not. The width-depth ratio decreases gradually with the erosion, and it is stable at about 1. The shallow- , The Reynolds number increases with the slope and rainfall intensity. The increase of tillage and catchment area caused the range of fluctuation of Reynolds number to become larger; shallow ditch water flow continuously changed between rapid and slow flow. Under the same conditions, the Fr value of shallow furrow flow decreased with tillage, and with the increase of rainfall intensity and slope, the effect of farming on Froude number became smaller and smaller. The conclusion of the study is of great significance to improve the slope erosion in loess area.