岩面形态对西南喀斯特坡地产流产沙的影响  

Influence of Rock Surface Morphology on Runoff and Sediment in Karst Slope of Southwest China

作　　者：敖利满 蒋超华 徐勤学[1,2] 方荣杰[1,2] 付智勇[4] 陈洪松[4] AO Liman;JIANG Chaohua;XU Qinxue;FANG Rongjie;FU Zhiyong;CHEN Hongsong(Key Laboratory for Theory and Technology of Environmental Pollution Control in Guangxi,Guilin University of Technology,Guilin,Guangxi 541004,China;Guangxi Collaborative Innovation Center for Water Pollution Control and Safety in Karst Area,Guilin University of Technology,Guilin,Guangxi 541004,China;Guangxi Nanning Survey and Design Institute of Pearl River Commission,Nanning 530007,China;Huanjiang Observation and Research Station for Karst Ecosystems,Chinese Academy of Sciences,Huanjiang,Guangxi 547100,China)

机构地区：[1]桂林理工大学广西环境污染控制理论与技术重点实验室科教结合科技创新基地,广西桂林541004 [2]桂林理工大学岩溶地区水污染控制与用水安全保障协同创新中心,广西桂林541004 [3]广西珠委南宁勘测设计院,南宁530007 [4]中国科学院环江喀斯特生态系统观测研究站,广西环江547100

出　　处：《水土保持研究》2023年第5期52-60,共9页Research of Soil and Water Conservation

基　　金：国家自然科学基金项目“岩—土覆被格局对岩溶峰丛洼地坡面水土流失的影响机制研究”(51769005),“多径流作用下喀斯特露天铝土矿区开挖边坡土壤侵蚀机理研究”(42067014)。

摘　　要：[目的]探明出露岩石的岩面形态对喀斯特坡地产流产沙特征的影响,为进一步认识喀斯特坡地降雨侵蚀规律提供科学依据。[方法]采用人工模拟降雨的方法,以无裸岩为对照,研究了在3个坡度(5°,15°,25°)条件下,岩面无发育(光滑)、岩面溶穴发育(溶穴)和岩面溶沟发育(溶沟)3种岩面形态对岩石出露坡面产流产沙特征的影响。[结果](1)与无裸岩相比,3种岩面形态均能显著增加地表径流,减少地下径流,其中溶穴平均地表径流系数最高(26.2%),溶沟平均地下径流系数最低(18.4%)。(2)地表初始产流时间与地下初始产流时间均受到岩面形态影响而有所提前,溶穴地表初始产流时间与地下初始产流时间均早于其他岩面形态。(3)裸露岩石拦截降雨形成的岩面流冲刷地表,加剧了地表产沙,地表产沙量大小呈现为光滑>溶穴>溶沟>无裸岩。(4)坡度为5°时,3种岩面形态均提升了地表径流携沙能力,坡度为15°时,光滑与溶穴提升了地表径流携沙能力,溶沟减弱了地表径流携沙能力,但坡度为25°时3种岩面形态均减弱了地表径流携沙能力。[结论]岩面形态对喀斯特坡地产流产沙影响显著,未来应加强对野外自然条件下不同岩面形态产流产沙的观测研究。[Objective]The aim of the study is to explore the influence of exposed rock surface morphology on the runoff and sediment yield of karst slope,and then to enhance the understanding of rainfall erosion pattern on karst slopes.[Methods]The artificially simulated rainfall experiment was used to study the effects of three types of rock surface morphology on the characteristics of runoff and sediment yields of karst slope with rock outcrops.With no bare rock as the control,three kinds of rock surface morphology(smoothness,karst cave,karst gully)and three slope gradients(5°,15°,25°)were set up.[Results](1)Compared with no bare rock,the three kinds of rock surface morphology all can significantly increase surface runoff and reduce underground runoff.The average surface runoff coefficient of karst cave is the highest(26.2%),and the average underground runoff coefficient of karst gully is the lowest(18.4%).(2)The initial surface runoff time and the initial underground runoff time are both advanced because of the effect of the rock surface morphology,and the initial surface runoff time and the initial underground runoff time of karst cave are both earlier than those of other rock surface morphology.(3)The rock surface flow formed by the process that bare rock intercepts rainfall scoures the surface,which intensifies the surface sediment yield.The surface sediment yield shows the following order:smoothness>karst cave>karst gully>no bare rock.(4)When the slope is 5°,the three types of rock surface morphology all improve the sediment carrying capacity of surface runoff.When the slope is 15°,the smoothness and karst cave improves the sediment carrying capacity of surface runoff,and the karst gully weakens the sediment carrying capacity of surface runoff.However,the three types of rock surface morphology all weaken the sediment carrying capacity of surface runoff when the slope is 25°.[Conclusion]The rock surface morphology has a significant effect on runoff and sediment yield in karst slope.In the future,the observation

关 键 词：岩面形态 产流产沙 喀斯特 坡度 模拟降雨 

分 类 号：S157.1[农业科学—土壤学]