Role of underground fissure flow in near-surface rainfall-runoff process on a rock mantled slope in the karst rocky desertification area
Role of underground fissure flow in near-surface rainfall-runoff process on a rock mantled slope in the karst rocky desertification area
复制标题
岩溶石漠化地区岩覆盖坡地表裂隙流近地表降雨径流过程中的作用
DOI：
10.1016/j.enggeo.2018.06.007
复制
发表时间：
2018-09-04
影响因子：
7.4
通讯作者：
Zhao, Longshan
中科院分区：
文献类型：
--
作者：
Peng, Xudong;Dai, Quanhou;Zhao, Longshan
由于喀斯特地区边坡具有复杂的近地表双层地质构造（即地表和地下裂隙），很难收集到所有流动的数据，特别是地下裂隙中产生的流动。这种信息的缺乏导致对喀斯特景观中与土壤流失相关的降雨径流过程的理解不足。本研究的目的是通过降雨实验，确定地表、地下和地下裂隙流的输出特征及其转换关系，以及地下裂隙流在近地表降雨径流过程中的作用。结果显示了以下发现。(i)小雨强（15和30毫米/小时）产生地下横向流和地下裂隙流，而大雨强除了产生地下流和地下流外，还产生地表径流。（ii）随着降雨强度的增加，上述各流量的径流/排水深度均增加，而径流/排水系数除地表径流外，没有明显的规律性变化。地表径流占总流量的分布比例随降雨强度的增加而增加，随地下裂隙程度的增加而减少，而地下裂隙流量的分布比例则相反。(3)地下裂隙流占总产流的主导地位，裂隙流的分布比例为27.8% ~ 78.0%。该研究对控制喀斯特石漠化地区的水土流失和水资源短缺具有重要意义，也提高了对该地区近地表降雨径流过程的认识
Because of the complex near-surface double-layer geologic structure (i.e., surface and underground fissures) of slopes in karst regions, it is difficult to collect data on all flows, especially the flows generated in underground fissures. This lack of information leads to a poor understanding of the rainfall-runoff process associated with soil loss in karst landscapes. The goal of this study was to determine the output characteristics of surface, subsurface and underground fissure flows and their conversion relationships, as well as the role of underground fissure flow in the near-surface rainfall-runoff process, using rainfall experiments. The results revealed the following findings. (i) Light rainfall intensities (15 and 30 mm/h) generated subsurface lateral flow and underground fissure flow, whereas greater rainfall intensities generated surface runoff in addition to subsurface and underground flows. (ii) The runoff/drainage depths of all the above flows increased with increasing rainfall intensity, while the runoff/drainage coefficient exhibited no obvious regular change, except for the surface runoff. Moreover, the distribution ratio of surface runoff to total flow also increased with increasing rainfall intensity but decreased with increasing underground fissure degree, while the distribution ratio of underground fissure flow exhibited the opposite trend. (iii) Underground fissure flow, with distribution ratios of 27.8-78.0%, dominated the total flow yield. This study has significance for controlling soil erosion and water shortage in the karst rocky desertification region and also improves the understanding of the near-surface rainfall-runoff process in this region