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选取我国西南喀斯特地区作为研究区域,以黄壤为试验土壤,通过人工降雨模拟喀斯特坡耕地坡面产流过程,探索其特征及影响因素。结果表明:(1)地表径流与降雨强度的变化呈极显著正相关关系,与地下孔(裂)隙度、岩石裸露率的变化均呈负相关;地下孔(裂)隙流与降雨强度、地下孔(裂)隙度及岩石裸露率的变化均呈正相关,但其相关性均较弱。随着坡度的增大,地表产流量呈先增大后减小,而地下孔(裂)隙流则表现为持续减小。(2)岩石裸露率、降雨强度、坡度和地下孔(裂)隙度等因子对地表径流的影响程度依次是降雨强度>坡度>地下孔(裂)隙度>岩石裸露率,其对地下径流的影响程度依次是坡度>降雨强度>地下孔(裂)隙度>岩石裸露率。(3)地表径流率随时间的变化总体特征为先迅速增大,然后缓慢减小,最后在50～60min以后趋于稳定,地下径流率总体呈现出随降雨历时增长而减小的趋势,但不同变化因素水平下地表及地下径流率随时间的变化差异都较大。
The Southwest Karst area in China was chosen as the research area, the yellow soil was used as the test soil, and the rainfall was simulated to simulate the runoff process of the karst slope. The characteristics and influencing factors were also explored. The results show that: (1) There is a significant positive correlation between surface runoff and rainfall intensity, which is negatively correlated with underground pore (fissure) porosity and rock bare rate. The ratio of underground fissures and rainfall intensity, Underground hole (fissure) porosity and rock bare rate changes were positively correlated, but the correlation is weak. With the increase of slope, the surface runoff increased first and then decreased, while the underground hole (split) gap flow showed a continuous decrease. (2) The influence degree of rock bareness, rainfall intensity, slope and underground hole (crack) porosity on surface runoff are rainfall intensity> slope> underground hole (fissure)> rock bare rate, The influence degrees are slope> rainfall intensity> underground hole (crack) porosity> rock bare rate. (3) The overall characteristics of the surface runoff over time changed rapidly firstly and then slowly, finally stabilized after 50 ~ 60min. The underground runoff rate generally showed a trend of decreasing with the increase of rainfall, The variations of surface and subsurface flow rate over time under different variation factors are quite different.