Runoff and erosion processes on bare slopes in the Karst Rocky Desertification Area
Runoff and erosion processes on bare slopes in the Karst Rocky Desertification Area
复制标题
喀斯特石漠化区裸坡径流与侵蚀过程
DOI：
10.1016/j.catena.2017.01.013
复制
发表时间：
2017-05-01
期刊：
影响因子：
6.2
通讯作者：
Zhao, Longshan
中科院分区：
文献类型：
--
作者：
Dai, Quanhou;Peng, Xudong;Zhao, Longshan
地下孔隙裂隙和基岩裸露是导致喀斯特地区土壤侵蚀机制复杂的主要因素。本研究的目的如下：a）测量岩溶裸坡地表和地下产生的径流和泥沙； b) 分析地下孔隙裂隙和基岩裸露率对土壤侵蚀的影响。为了实现这些目标，我们设计了一个实验，改变地下孔隙裂隙程度和基岩裸露率，并测量它们对土壤侵蚀的影响。结果表明：i)地表径流和地下产沙量随降雨强度的增加而增加，且降雨强度越大更容易产生地表径流； ii) 地表产流量随着基岩裸露率的增加先增加后减少，而地下孔隙裂隙产流量则随着基岩裸露率的增加而增加；因此，地表产沙量与地下孔隙裂隙产沙量呈现出先减少后增加的相同规律； iii) 地表径流和泥沙总体上随着地下孔隙裂隙程度的增加而减少，但地下孔隙裂隙则呈现出不同的规律； iv) 降雨强度、基岩裸露率和地下孔隙裂隙度是影响岩溶裸坡土壤侵蚀过程的重要因素，因为基岩裸露率和地下孔隙裂隙度是造成土壤表层和地下径流和泥沙分布不均匀的主要因素。因此，地下孔隙裂隙水土流失是喀斯特地区土壤侵蚀过程与其他地区的特殊模式和主要区别。这些成果对于认识喀斯特地区土壤侵蚀机制、控制水土流失具有理论和实践意义。
Underground pore fissure and bedrock bareness are the main factors that lead to complicated mechanisms of soil erosion in karst regions. The objectives of this study were as follows: a) to measure runoff and sediment generated from the surface and underground in the karst bare slope; and b) to analyse the impacts of underground pore fissures and bedrock bareness rates on soil erosion. To achieve these objectives, we designed an experiment in which underground pore fissure degrees and bedrock bareness rates were varied, and their impacts on soil erosion were measured. The results showed that i) runoff and sediment yields from the surface and underground increased with increasing rainfall intensity, and the surface runoff was much more easily generated when the rainfall intensity was greater; ii) surface runoff yield first increased and then decreased with increasing bedrock bareness rates, while the runoff yield in underground pore fissures increased with increasing bedrock bareness rates; thus, sediment production on the surface and in underground pore fissures showed the same pattern, i.e., first decreased and then increased; iii) the surface runoff and sediment generally decreased with increasing degrees of underground pore fissures, while that of underground pore fissures presented a different pattern; and iv) rainfall intensity, bedrock bareness rates and underground pore fissure degrees were the important factors affecting soil erosion processes in karst bare slopes because the bedrock bareness rates and underground pore fissure degrees were the main factors causing the uneven distribution of runoff and sediment on soil surfaces and underground. Therefore, soil and water loss in underground pore fissures was the special pattern and main difference in soil erosion processes in the karst region compared with other regions. These results have theoretical and practical significance for understanding soil erosion mechanisms and controlling soil and water loss in karst regions.