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以福建省安溪县龙门镇崩岗土为对象,通过室内模拟降雨试验,研究在120mm/h雨强条件下,不同秸秆覆盖度(0,25%,50%,75%和100%)和坡度(25°,30°和35°)组合坡面的侵蚀情况。结果表明:(1)秸秆覆盖能够有效延长坡面产流时间,且随着覆盖度的增加产流时间相应延长。(2)在降雨初期,不同条件下的前期径流量随着降雨的进行迅速增加,30°和35°坡面不同覆盖度径流量在降雨中后期起伏较大,30°坡面的径流量明显小于25°和35°坡面。(3)坡面的产沙量变化过程表现为当覆盖度较低时,坡面产沙量较大;当覆盖度处于中等偏上水平时,产沙量始终处于较低水平;当覆盖度达到最高时,产沙量先增加后降低最后趋于稳定。(4)30°和35°坡面径流量的临界覆盖度为50%,不同坡度产沙量的临界覆盖度为75%。(5)可利用经验方程对不同覆盖度和坡度条件下崩积体坡面产沙量进行预测。
Aiming at the collapsing soil in Longmen Town, Anxi County, Fujian Province, indoor simulated rainfall experiments were conducted to study the effects of different straw mulching rates (0, 25%, 50%, 75% and 100% (25 °, 30 ° and 35 °) combined slope erosion. The results showed that: (1) straw mulching could effectively prolong the runoff generation time, and with the increase of the coverage, the runoff time extended accordingly. (2) In the early stage of rainfall, the runoff at the early stage under different conditions increased rapidly with the increase of rainfall. The runoff with different coverage at the 30 ° and 35 ° slopes varied greatly in the middle and late stages of rainfall, and the runoff on the 30 ° slope was significant Less than 25 ° and 35 ° slope. (3) The variation of sediment yield on the slope shows that when the coverage is low, the sediment yield is larger; when the coverage is above the upper level, the sediment yield is always low; when the coverage At its highest level, the amount of sediment increases first and then decreases and finally stabilizes. (4) The critical coverage of runoff at 30 ° and 35 ° is 50%, and the critical coverage of sediment yield at different slopes is 75%. (5) The empirical equation can be used to predict the sediment yield of the slope of the disintegration body under different coverage and slope conditions.