岩溶石山区山坡表层径流水文动态特征对比分析——以桂林丫吉试验场为例

选择桂林丫吉试验场溶洞—硝岩洞及其上方的汇水坡面作为研究区,通过在不同降雨条件下,对坡面径流和硝盐洞中流水水文动态进行监测并做对比分析研究。结果表明:（1）降雨强度、降雨持续时间和各含水系统前期含水情况决定了岩溶石山区坡面地表和包气带水文动态变化过程;（2）在不同降雨条件下,地表坡面流和经过上部包气带调蓄过的硝盐洞水文动态都表现为暴涨暴落,坡面径流表现的更为明显,一般坡面径流的整个水文过程持续几个小时到十几个小时,而硝盐洞中流水水文过程持续13d;（3）一般大到暴雨条件下,坡面流最大流量大于硝盐洞,但由于持续时间短,其一场降雨后所获得的水量远不如下渗到包气带—硝盐洞中滴水水量。

Comparative Analysis of Surface Runoff Hydrologic Dynamic Characteristics in Karst Mountainous Areas: Taking Yaji Experimental Station as Study Case

Choosing the Xiaoyan Cave located on Yaji Karst Experimental Site in Guilin and the above catchment slope as research area, this paper made a study via conducting dynamic monitor of the slope runoff and cave shaft flow in different rainfall conditions, the results show that (1) The slope runoff and vadose zone hydrologic dynamic change process in karst mountainous areas are decided by rainfall intensity, rainfall duration and the condition of the water-bearing medium prophase water situation; (2) In different rainfall conditions, the hydrologic dynamic changes of slope runoff and cave shaft flow rise and fall rapidly, and the slope runoff even more rapidly than the cave shaft flow. In general, the hydrologic dynamic change process of slope runoff last for a few hours to ten hours, but the cave shaft flow can last one to three days; (3) When the time of heave rain or downpour, the slope maximum runoff is greater than the cave shaft flow, but the water volume in slope runoff are less than the cave shaft flow due to the short duration of the slope runoff hydrology dynamic.