中国岩溶
中國巖溶
중국암용
CARSOLOGICA SINICA
2014年
3期
356-362
,共7页
喀斯特地区%模拟降雨%裸坡面%坡面侵蚀
喀斯特地區%模擬降雨%裸坡麵%坡麵侵蝕
객사특지구%모의강우%라파면%파면침식
karst area%simulated rainfall%bare slope%slope erosion
文章通过人工模拟降雨试验,研究不同地下孔(裂)隙度、基岩裸露率和雨强对地表、地下产流、产沙的影响,其结果表明:(1)土壤侵蚀与地下孔(裂)隙度具有较高相关性,地表产流、产沙随地下孔(裂)隙度的增大而减小,而地下则相反;(2)坡面径流刚产生时,雨滴击溅和薄层水流冲刷,土壤细小颗粒堵塞其毛管空隙,渗漏率减小,而地表径流量增大,土壤团聚体被破坏、分散和迁移,降水与土壤渗漏率增大,地表径流量减小,雨滴击溅增强,如此循环,降水与土壤渗漏率呈波动性变化;总体而言,地表、地下悬移质均随降雨历时呈下降趋势,而地表推移质则相反,地表、地下产流量变幅较小,趋于平行;(3)地表产流、产沙量随基岩裸露率增大呈波动性变化,总体呈下降趋势;而地下产流、产沙量随基岩裸露率增大呈波动性变化,总体呈增大趋势;(4)在较小雨强30 mm/h 时,地表只产生悬移质流失,没有产生推移质流失;地表、地下产流、产沙都是随雨强增大而增大;雨强由30 mm/h 增大到150 mm/h,地表累积产流量为538.5 L,累积产沙量为2393.81 g,地下累积产流量为207.8 L,累积产沙量为687.73 g,累积产沙量的递增速率比累积产流量的递增速率要大,地表产流、产沙的递增速率大于地下产流、产沙的递增速率;(5)各因子与土壤侵蚀间相关程度为:降雨历时>雨强>地下孔(裂)隙度>基岩裸露率。该实验有助于为喀斯特地区的水土流失研究、评价及制订石漠化治理措施提供理论依据。
文章通過人工模擬降雨試驗,研究不同地下孔(裂)隙度、基巖裸露率和雨彊對地錶、地下產流、產沙的影響,其結果錶明:(1)土壤侵蝕與地下孔(裂)隙度具有較高相關性,地錶產流、產沙隨地下孔(裂)隙度的增大而減小,而地下則相反;(2)坡麵徑流剛產生時,雨滴擊濺和薄層水流遲刷,土壤細小顆粒堵塞其毛管空隙,滲漏率減小,而地錶徑流量增大,土壤糰聚體被破壞、分散和遷移,降水與土壤滲漏率增大,地錶徑流量減小,雨滴擊濺增彊,如此循環,降水與土壤滲漏率呈波動性變化;總體而言,地錶、地下懸移質均隨降雨歷時呈下降趨勢,而地錶推移質則相反,地錶、地下產流量變幅較小,趨于平行;(3)地錶產流、產沙量隨基巖裸露率增大呈波動性變化,總體呈下降趨勢;而地下產流、產沙量隨基巖裸露率增大呈波動性變化,總體呈增大趨勢;(4)在較小雨彊30 mm/h 時,地錶隻產生懸移質流失,沒有產生推移質流失;地錶、地下產流、產沙都是隨雨彊增大而增大;雨彊由30 mm/h 增大到150 mm/h,地錶纍積產流量為538.5 L,纍積產沙量為2393.81 g,地下纍積產流量為207.8 L,纍積產沙量為687.73 g,纍積產沙量的遞增速率比纍積產流量的遞增速率要大,地錶產流、產沙的遞增速率大于地下產流、產沙的遞增速率;(5)各因子與土壤侵蝕間相關程度為:降雨歷時>雨彊>地下孔(裂)隙度>基巖裸露率。該實驗有助于為喀斯特地區的水土流失研究、評價及製訂石漠化治理措施提供理論依據。
문장통과인공모의강우시험,연구불동지하공(렬)극도、기암라로솔화우강대지표、지하산류、산사적영향,기결과표명:(1)토양침식여지하공(렬)극도구유교고상관성,지표산류、산사수지하공(렬)극도적증대이감소,이지하칙상반;(2)파면경류강산생시,우적격천화박층수류충쇄,토양세소과립도새기모관공극,삼루솔감소,이지표경류량증대,토양단취체피파배、분산화천이,강수여토양삼루솔증대,지표경류량감소,우적격천증강,여차순배,강수여토양삼루솔정파동성변화;총체이언,지표、지하현이질균수강우력시정하강추세,이지표추이질칙상반,지표、지하산류량변폭교소,추우평행;(3)지표산류、산사량수기암라로솔증대정파동성변화,총체정하강추세;이지하산류、산사량수기암라로솔증대정파동성변화,총체정증대추세;(4)재교소우강30 mm/h 시,지표지산생현이질류실,몰유산생추이질류실;지표、지하산류、산사도시수우강증대이증대;우강유30 mm/h 증대도150 mm/h,지표루적산류량위538.5 L,루적산사량위2393.81 g,지하루적산류량위207.8 L,루적산사량위687.73 g,루적산사량적체증속솔비루적산류량적체증속솔요대,지표산류、산사적체증속솔대우지하산류、산사적체증속솔;(5)각인자여토양침식간상관정도위:강우력시>우강>지하공(렬)극도>기암라로솔。해실험유조우위객사특지구적수토류실연구、평개급제정석막화치리조시제공이론의거。
Karst is widely distributed in China where carbonate rocks,including buried karst,account for up to 3,463,000 km2 .Strata with carbonate rock formations comprise 2,060,000 km2 ,while carbonate rocks outcrop over 907,000 km2 .The karst system,which is faces serious soil erosion problems,is an ecologically fragile system due to its high sensitivity,low catastrophe capacity and small environmental capacity.There-fore,study of soil erosion in karst areas is important.The impacts of fissure porosity,bedrock outcrop per-centage and rainfall intensity on underground runoff and sediment yield were evaluated using simulated rain-fall.The results provide a theoretical basis for future evaluation and prevention of soil erosion in karst areas. The results showed,(1)Soil erosion has a high correlation with porosity or fracture aperture;(2)Soil infil-tration rate is dependent on rainfall.Surface and subsurface suspended sediment decrease with rainfall dura-tion,while surface bed material load increases;(3)In general,the amount of surface runoff and sediment decreases with the bedrock outcrop rate,while the amount of underground runoff and sediment increases;(4)Only suspended sediment loss took place on the surface.No bed material load loss occurred with rainfall intensity of 30 mm/h.The runoff and sediment yield increase with rainfall intensity.For instance,when rain intensity increased from 30 mm/h to 150 mm/h,the cumulative surface runoff was 538.5 L,cumulative sur-face sediment yield 2,393.81 g,cumulative underground runoff 207.8 L and cumulative underground sedi-ment yield 687.83 g.The rate of increase in the cumulative sediment yield is greater than the rate of increase in the cumulative runoff,and the rate of increase in the surface runoff and sediment yield is greater than that of the underground runoff and sediment yield;(5)The correlation between soil erosion and each individual factor indicates that the relative impact of each factor on soil erosion is,rainfall duration > rainfall intensity> underground porosity > bedrock outcrop.