考虑种植草本植被时红壤坡面的侵蚀情况,采用室内人工模拟降雨的方法,在强降雨(雨强2.0 mm/min)、短历时(30 min)情况下,研究不同坡度、不同植被覆盖度下红壤坡面抗侵蚀效应.结果表明:当植被覆盖度＜40％时,随着植被覆盖度的增加,侵蚀量迅速降低,当植被覆盖度＞60％时,侵蚀量减小趋于平缓,故本研究的临界植被覆盖度为40％ ～ 60％;对于不同植被覆盖度的红壤坡面,其临界坡度也发生了变化,当植被覆盖度＜40％时,临界坡度较裸露坡面逐渐减小,当植被覆盖度＞60％时,随着坡度的增加侵蚀量缓慢递增,试验中没有出现临界坡度.分析其原因,指出临界坡度是土壤内在性质、植被特性、降雨等因素综合作用的结果,并不是一个常数.%Comprehensively considering the erosion of red soil slope with herbaceous vegetation,indoor simulated rainfall experiments are carried out to discuss the anti-erosion effect with different slopes and different vegetation coverages of red soil slope in heavy rainfall(2.0 mm/min)and short duration(30 min).The results show that with the increase of vegetation coverage,the erosion reduces rapidly within the vegetation coverage less than 40％ while the erosion reduces gently as the vegetation coverage more than 60％,so the critical vegetation coverage is 40％-60％;The critical slope changes for different vegetation coverages,The critical slope reduces within the vegetation coverage less than 40％ while The critical slope disappears as the vegetation coverage more than 60％ because the erosion increases gently.The reason led to this phenomenon is that the critical slope can be effected by soil properties,vegetation coverage,rainfall and so on.
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