连续降雨条件下工程堆积体产流产沙对砾石含量的响应  

Response of Runoff and Sediment Yield to Gravel Content in Engineered Deposit Slopes Under Continuous Rainfall Conditions

作　　者：王子吟 魏育超 李镇 骆汉 谢永生[1,2] Wang Ziyin;Wei Yuchao;Li Zhen;Luo Han;Xie Yongsheng(College of Soil and Water Conservation Science and Engineering,Northwest A&F University,Yangling,Shaanxi 712100,China;Institute of Soil and Water Conservation,Chinese Academy of Science and Ministry of Water Resources,Yangling,Shaanxi 712100,China;Power China Kunming Engineering Corporation Limited,Kunming,Yunnan 650000,China)

机构地区：[1]西北农林科技大学水土保持科学与工程学院,陕西杨凌712100 [2]中国科学院水利部水土保持研究所,陕西杨凌712100 [3]中国电建集团昆明勘测设计院有限公司,云南昆明650000

出　　处：《水土保持通报》2024年第2期91-100,共10页Bulletin of Soil and Water Conservation

基　　金：国家自然科学基金项目“生产建设项目工程堆积体坡面微地貌演化及其与产流产沙的耦合关系研究”(41601300);承德国家可持续发展议程创新示范区建设科技专项项目“承德市接坝区生态重建及水源涵养能力提升关键技术研究”(202104F003);四川省交通运输科技项目(2018-ZL-15)。

摘　　要：[目的]探究连续降雨条件下不同砾石含量对陕北沙壤土上方有来水工程堆积体坡面产流产沙的影响,为生产建设项目水土流失治理提供数据支撑和理论参考。[方法]通过室内模拟降雨试验,研究不同砾石含量(0,10%,20%,30%,40%)工程堆积体坡面土壤水动力学特性及产流产沙特征。[结果]①降雨强度相同,随砾石含量增加,工程堆积体坡面初始产流时间表现为递减趋势,减幅为27.22%~64.62%,35.09%~71.70%,47.37%~78.77%,51.75%~82.31%。次降雨径流率表现为“迅速增加—稳定波动”的变化趋势,平均径流率随砾石含量、降雨时间的增加显著增大;但产流峰值随砾石含量增加而降低,且出现时间逐渐提前。②试验各场次雷诺数的变化范围介于74.13~165.05,均小于500,水流属于层流;弗劳德数的变化范围集中在2.14~3.71,表现为急流。水流剪切力、水流功率和单位水流功率随降雨场次的增加而显著增加。③0%~40%砾石含量工程堆积体坡面侵蚀速率介于0.45~6.73,0.13~4.09,0.25~1.26,0.14~0.96,0.13~0.88 g/(m^(2)·min),各砾石含量堆积体减沙幅度分别为36.06%,49.05%,55.23%和56.62%,其中砾石高覆盖度(40%)的沙壤土工程堆积体坡面土壤侵蚀强度较小。[结论]砾石覆盖在沙壤土工程堆积体坡面的水土流失过程中可显著降低土壤侵蚀速率,从而实现拦蓄水土,保持较高的减沙效益。[Objective]The impact of different gravel contents on soil erosion of engineered deposit slopes were explored in the sandy soil region of Northern Shaanxi Province under continuous rainfall conditions in order to provide data support and theoretical references for soil erosion control in production and construction projects.[Methods]Indoor rainfall experiments were conducted to study the hydrodynamic,runoff,and sediment characteristics of engineered deposit slopes with varying gravel contents(0%,10%,20%,30%,40%).[Results]①Under the same rainfall intensity,the initial runoff time on the engineered deposit slopes showed a decreasing trend with the increase of gravel content,with ranges of 27.22%—64.62%,35.09%—71.70%,47.37%—78.77%,and 51.75%—82.31%,respectively.The runoff coefficient during subsequent rainfall events exhibited a“rapid increase-stable fluctuation”trend,and the average runoff coefficient increased significantly with increasing gravel content and rainfall duration.However,the peak value of runoff decreased with increasing gravel content,and the occurrence time of the runoff peak was gradually advanced.②The Reynolds index for all experiments ranged from 74.13 to 165.05,all of which were below 500,indicating that the flow type was laminar flow,while the Froude number ranged from 2.14 to 3.7l indicating rapid flow.The shear force,flow power,and unit flow power increased with increasing rainfall time.③The ranges of erosion modulus on the engineered deposit slopes were 0.45—6.73,0.13—4.09,0.25—1.26,0.14—0.96,and 0.13—0.88 g/(m^(2)·min),respectively.The sediment reductions for each gravel content were 36.06%,49.05%,55.23%,and 56.62%,respectively.The highest gravel coverage(40%)resulted in the lowest soil erosion intensity of the engineered deposit slopes in the sandy soil region.[Conclusion]Gravel coverage on engineered deposit slopes of sandy loam soil significantly reduces soil erosion rate,thereby achieving soil retention and maintaining high sediment reduction benefits.

关 键 词：工程堆积体 砾石含量 连续降雨 产流产沙 

分 类 号：S157.1[农业科学—土壤学] P333.5[农业科学—农业基础科学]