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地表糙度是影响土壤侵蚀的因素之一。为进一步明确地表糙度的侵蚀效应,通过野外模拟降雨试验,研究了地表糙度在降雨前后、不同坡度、不同植被覆盖度、不同空间坡段的动态变化特征,探讨了地表糙度变化规律及其影响因素。结果表明:在降雨过程中,土地利用类型、雨强、降雨顺序、坡度和植被覆盖度都会对糙度产生影响。随着降雨场次的增加,地表糙度逐渐增大;在试验范围内,坡度越大,地表糙度增加幅度越大,增加趋势越明显;植被覆盖度越大,地表糙度变化越小。坡面的各个坡段变化情况整体遵循上述规律,但在某些坡段内出现空间变异性,导致有些坡段可以拦蓄径流泥沙,消减侵蚀,而有些坡段可以增加潜在的冲刷,加剧侵蚀;多个因子以及因子间的交互效应成为影响糙度变化的主要因素。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,同时也为黄土高原水土流失治理奠定理论基础。
Surface roughness is one of the factors affecting soil erosion. In order to further clarify the erosive effect of surface roughness, the dynamic variation characteristics of surface roughness before and after rainfall, different slopes, different vegetation coverage and different spatial slope sections were studied through field simulation rainfall test. Its influencing factors. The results show that the types of land use, rainfall intensity, rainfall sequence, slope and vegetation coverage all affect the roughness during rainfall. With the increase of rainfall times, the surface roughness gradually increases. Within the experimental range, the greater the slope, the greater the increase of surface roughness, the more obvious the increasing trend. The larger the vegetation coverage, the smaller the change of surface roughness. The variation of each slope section of the slope obeys the above law, but the spatial variability appears in some slope sections. As a result, some slope sections can hold runoff and sediment and reduce erosion, while some slope sections can increase potential erosion and aggravate erosion ; Multiple factors and the interaction between factors become the main factors affecting the change of roughness. The results provide some theoretical basis for revealing the erosion characteristics of the surface roughness, and also lay a theoretical foundation for soil and water loss control of the Loess Plateau.