弃渣扰动对藏东山地草甸坡面产流产沙的影响  

Influence of Slag Disposal Disturbance on Runoff and Sediment Yield in Mountain Meadow of Eastern Xizang

作　　者：李亚桐 王冠 冉心昊 肖辉杰[1] Li Yatong;Wang Guan;Ran Xinhao;Xiao Huijie(School of Soil and Water Conservation,Beijing Forestry University,Beijing 100083,China)

机构地区：[1]北京林业大学水土保持学院,北京100083

出　　处：《水土保持研究》2024年第4期105-113,共9页Research of Soil and Water Conservation

基　　金：国家重点研发计划项目“西南高山峡谷区水土流失综合防治技术与示范”(2022YFF1302901)。

摘　　要：[目的]明晰铁路修建中弃渣工程扰动引起的水土流失响应,揭示弃渣堆积前后及其植被恢复对藏东生态脆弱的山地草甸区坡面尺度水土流失的影响。[方法]选取未扰动、轻度扰动、重度扰动、覆土恢复4个类型的坡面,建立原位径流小区,通过人工模拟降雨试验,开展了坡面产流产沙过程的研究。[结果](1)坡面的溅蚀量随扰动强度的增大而增加,下坡向的溅蚀量为上坡溅蚀量的1.14~2.67倍。(2)轻度扰动坡面、重度扰动坡面和覆土恢复坡面的初始产流时间分别缩短为未扰动坡面的53.8%~66.7%,34.6%~46.7%,86.7%~92.9%。(3)未扰动坡面、轻度扰动坡面、重度扰动坡面和覆土恢复坡面的产流速率分别为44~86,104~147,200~373,46~95 ml/(min·m^(2)),产沙速率分别为0.026~0.055,0.05~0.098,1.034~2.189,0.047~0.077 g/(min·m^(2))。[结论]覆土恢复坡面的水土保持能力较轻度扰动和重度扰动坡面有显著提高,但距未扰动坡面仍有差距,需采取其他植被或工程措施对工程扰动坡面加以恢复。[Objective]The aims of this study are to elucidate the response of soil and water loss resulting from slag dumping engineering disturbances during railway construction,and to unveil the impact of slag accumulation and vegetation restoration on soil and water loss at a slope scale in the ecologically fragile mountain meadow region of eastern Xizang.[Methods]Four slope types such as undisturbed,mildly disturbed,severely disturbed,and disturbed then covered with soil restoration were selected.The in-situ runoff plots were established.The process of sediment production and loss on slope was monitored by artificially simulated rainfall experiment.[Results](1)The quantity of spattering on the slope increased with the intensity of disturbance,with the amount on the downhill side being approximately 1.14 to 2.67 times greater than that on the uphill side.(2)The initial flow generation time for the lightly disturbed slope,heavily disturbed slope,and covered slope reduced from 53.8%to 66.7%,34.6%to 46.7%,and 86.7%to 92.9%,respectively.(3)The flow production rates for the undisturbed slope,lightly disturbed slope,heavily disturbed slope,and covered slope ranged from 44 to 86 ml/(min·m^(2)),104 to 147 ml/(min·m^(2)),200 to 373 ml/(min·m^(2)),and 46 to 95 ml/(min·m^(2)),respectively.The sediment production rates ranged from 0.026 to 0.055 g/(min·m^(2)),0.05 to 0.098 g/(min·m^(2)),1.034 to 2.189 g/(min·m^(2)),and 0.047 to 0.077 g/(min·m^(2)),respectively.[Conclusion]The soil and water conservation capacity of the restored slope has been significantly improved in comparison to the lightly disturbed and heavily disturbed slopes.However,there still exists a disparity between the undisturbed slope and the covered slope.Therefore,additional vegetation or engineering measures need to be implemented to restore the disturbed slope effectively.

关 键 词：产流产沙过程 水土流失 人工模拟降雨 高山草甸 弃渣工程 

分 类 号：S157.1[农业科学—土壤学]