Abstract Due to the great difficulty of monitoring surface and underground runoff and sediment yield directly, the surface and underground hydrological processes associated with soil leakage loss in karst trough valleys remain unknown. The objective of this study was to analyse the role of the rock dip angle in the water and soil leakage loss processes, to assess the characteristics of surface and underground runoff and soil erosion and to investigate their conversion relationships using rainfall experiments. The results showed the following. i) At a steep rock dip angle (60°), the underground runoff yield had a shorter stabilization time than the surface runoff yield and that the underground runoff coefficient of the dip slope exceeded 0.5. ii) The surface sediment yield could be divided into the suspended load and the bed load and the underground sediment yield included only the suspended load. On the anti-dip slope, the surface erosion modulus was 0.83–2.50 times the underground erosion modulus. iii) The surface and underground cumulative runoff was linearly correlated with the cumulative sediment yield. The rock dip angle had a significant quadratic relationship with the surface and underground runoff and sediment yield. These results improve the understanding of the surface-underground runoff and soil erosion processes and have significance for preventing water and soil leakage loss on the slopes of karst trough valleys.

中文翻译：

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岩溶槽谷倾角/反倾坡径流和土壤侵蚀过程中岩石倾角的作用

摘要 由于地表和地下径流产沙量的直接监测难度很大，与岩溶槽谷土壤渗漏损失相关的地表和地下水文过程尚不清楚。本研究的目的是分析岩石倾角在水土流失过程中的作用，评估地表和地下径流和土壤侵蚀的特征，并通过降雨实验研究它们的转换关系。结果如下。i) 在陡峭的岩石倾角（60°）下，地下产流比地表产流稳定时间更短，倾角地下产流系数超过0.5。ii) 表层产沙量可分为悬浮荷载和底床荷载，地下产沙量仅包括悬吊荷载。在反倾坡上，地表侵蚀模数为地下侵蚀模数的0.83～2.50倍。iii) 地表和地下累积径流与累积产沙量呈线性相关。岩石倾角与地表和地下径流产沙量呈显着的二次关系。这些结果提高了对地表-地下径流和水土流失过程的认识，对防止岩溶槽谷边坡的水土流失流失具有重要意义。iii) 地表和地下累积径流与累积产沙量呈线性相关。岩石倾角与地表和地下径流产沙量呈显着的二次关系。这些结果提高了对地表-地下径流和水土流失过程的认识，对防止岩溶槽谷边坡的水土流失流失具有重要意义。iii) 地表和地下累积径流与累积产沙量呈线性相关。岩石倾角与地表和地下径流产沙量呈显着的二次关系。这些结果提高了对地表-地下径流和水土流失过程的认识，对防止岩溶槽谷边坡的水土流失流失具有重要意义。