摘要
[目的]研究短历时强降雨对喀斯特坡耕地产流产沙的影响,揭示喀斯特坡耕地土壤侵蚀特征机理,为解决喀斯特坡耕地土壤侵蚀和保障粮食生产提供科学依据。[方法]通过人工模拟降雨试验,以喀斯特裸坡地和玉米坡地为研究对象,研究短历时强降雨对喀斯特坡耕地产流产沙的影响。[结果](1)裸坡地和玉米地地表产流产沙模数随坡度的增大而增大,当坡度相同时,玉米地地表产流产沙模数显著小于裸坡地(p<0.05);随着降雨历时的增加,裸坡地和玉米地地表产流模数呈现出先增大后保持稳定的趋势,而地表产沙模数则是先增大后减小。(2)裸坡地和玉米地各壤中流产流模数随坡度的增大而增大;当坡度相同时,玉米地各壤中流产流量显著小于裸坡地(p<0.05),其中坡度为20°时,玉米地壤中流(15—25 cm)总产流量相对裸坡地减少了62.59%。(3)当坡度不变时,玉米地地下产沙量和产沙模数显著小于裸坡地(p<0.05);随着降雨历时的增加,裸坡地与玉米地地下产流模数呈现出不断增大的趋势,其变化趋势基本保持一致,而地下产沙模数呈现先增大后减小的趋势,在20~30 min之间达到最大产沙模数。(4)比较不同坡度裸坡地与玉米地各产流产沙之间的相关性,发现玉米地相比裸坡地地下产沙与地表产流、地下产流、地表产沙之间相关性增强,而地表产沙与地表产流、地下产流之间的相关性减弱。[结论]强降雨下玉米坡地能够增加入渗,具有阻控和缓蚀的作用,其中地表产流产沙模数和壤中流产流模数随坡度的增大而增大,而地下产流模数随降雨历时增加呈不断增大的趋势,地下产沙模数呈先增大后减小的趋势。
[Objective] The effects of short-duration high-intensity rainfall on runoff and sediment yield in a karst slope farmland were analysed to reveal the mechanism of soil erosion,in order provide a scientific basis for reducing it,and ensuring food production in karst slope farmlands.[Methods] Through simulated rainfall experiments,the effects of short-duration high-intensity rainfall on the runoff and sediment yields over a karst slope farmland were studied by taking a karst bare slope and a corn slope as research objects.[Results](1) Surface runoff and sediment yield moduli of both bare and corn slopes increased with the rise of the slope.At similar slopes,the surface runoff and sediment yield moduli of the corn slope were much less than those of the bare slope(p<0.05).With the increase of rainfall duration,the surface runoff yield moduli of both bare and corn slopes increased first and then remained stable,while the surface sediment yield moduli increased first and then decreased.(2) The runoff yield moduli of the respective subsurface runoffs of bare and corn slopes increased with the rise of the slope.At a similar slope,the runoff yield of respective subsurface runoffs in the corn slope was much less than that in the bare slope(p<0.05),whereas when slope was 20°,the total runoff yield of the corn slope's subsurface runoffs(15—25 cm) decreased by 62.59% compared with that of the bare slope.(3) When the slope was fixed,underground runoff and sediment yield moduli of the corn slope were much less than those of the bare slope(p<0.05).With the increase of rainfall duration,the underground runoff yield moduli of both bare and corn slopes showed a trend of continuous increase,where their changes were basically consistent,while the underground sediment yield moduli showed a trend of first increasing and then decreasing and reached a maximum between 20 min and 30 min.(4) By comparing the correlations between the runoff and sediment yields of the bare and the corn slopes under different slopes,it was found that the cor
作者
杨应冲
戴全厚
王勇
张友
姚一文
Yang Yingchong;Dai Quanhou;Wang Yong;Zhang You;Yao Yiwen(College of Forestry,Guizhou University,Guiyang,Guizhou 550025;Soil Erosion and Ecological Restoration Research Center,Guizhou University,Guiyang,Guizhou 550025)
出处
《水土保持通报》
CSCD
北大核心
2024年第4期126-134,共9页
Bulletin of Soil and Water Conservation
基金
国家自然科学基金项目“喀斯特碳酸盐岩与碎屑岩交互区坡面土壤侵蚀过程与机理”(42167044)。
关键词
喀斯特坡耕地
短历时强降雨
产流模数
产沙模数
karst slope farmland
short-duration high-intensity rainfall
runoff yield modulus
sediment yield modulus
