北方风沙区砾石对堆积体坡面径流及侵蚀特征的影响  

Effect of gravel on runoff and erosion characteristics on engineering accumulation slope in windy and sandy area, northern China

作　　者：康宏亮[1] 王文龙[1,2] 薛智德[3] 郭明明[1] 李建明[4] 白芸[5] 邓利强[6] 李艳富 李垚林[8] 

机构地区：[1]西北农林科技大学水土保持研究所黄土高原土壤侵蚀与旱地农业国家重点实验室,杨凌712100 [2]中国科学院水利部水土保持研究所,杨凌712100 [3]西北农林科技大学资源环境学院,杨凌712100 [4]长江科学院水土保持研究所,武汉430010 [5]榆林学院生命科学学院,榆林719000 [6]山东省水利科学研究院水土保持与生态研究所,济南250013 [7]南京水利水电科学院,南京210029 [8]黄河水利委员会西峰水土保持科学试验站,庆阳745000

出　　处：《农业工程学报》2016年第3期125-134,共10页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金项目(40771127);水利部公益性行业专项(201201048;201201047)

摘　　要：为了研究砾石对工程堆积体降雨侵蚀规律的影响,采用室内人工模拟试验,以土质堆积体（砾石质量分数为0）为对照,研究了10%、20%和30%砾石质量分数堆积体边坡在模拟降雨条件下的径流水力特征、产沙过程及侵蚀动力机制。结果表明：1）产流0~6 min,砾石促进堆积体坡面细沟间径流流动;产流12~30 min后,砾石阻碍堆积体坡面细沟径流流动;2）含砾石堆积体坡面粗糙度增大,水流流态变缓,水流速度降低,且均以层流为主。较土质堆积体而言,30%砾石质量分数堆积体坡面阻力系数增大88.8%~288.4%,弗汝德数降低28.9%~41.8%,水流速度降低0~45.8%;3）径流含沙量随产流历时经历快速降低-平稳过渡-波动上升3个阶段,土质及10%砾石质量分数堆积体高含沙水流现象频发,且随雨强增大,重力坍塌次数增加,重力侵蚀程度增强。20%、30%砾石质量分数堆积体发生高含沙水流的几率约为0。相对土壤流失比与砾石质量分数呈极显著负指数函数关系;4）土壤剥蚀率与各侵蚀动力参数均可用简单线性函数关系描述,单位径流功率是描述风沙区土质和10%砾石质量分数工程堆积体侵蚀产沙的最优因子,径流功率是刻画20%、30%砾石质量分数工程堆积体土壤侵蚀参数更为合理的因子。结果可为全国范围工程堆积体土壤侵蚀模型的建立提供科学依据。Different from abandoned field and cropland and natural landscape, engineering accumulation is a special man-made geomorphic unit and has been found much more serious soil erosion. The anthropogenic accelerating erosion poses great threat to ecological environment of construction sites with surrounding regions and seriously hinders local economic growth and improvement of people＇s living standard. Gravel is always an important composition of depositions and it causes particular erosion characteristics. An indoor artificially simulated rainfall experiment was carried out in the State Key Laboratory of Soil Erosion and Dryland Agriculture on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, China to investigate runoff hydraulic character and sediment yield process and erosion dynamic mechanism on slope of engineering deposition with different content of gravel. Soil sample, collected from Jingbian, Shanxi （N37°26′08″, E108°54′53″）, was evenly mixed with gravel to be used as the main test material. According to preliminary field investigations, the grain diameter≤50mm of gravel was chosen as the gravel for the test and divided into 3 classes with different ranges of diameter： 2-14 mm （small） and 14-25 mm （medium） and 25-50 mm （large）. Gravel sample for each test was consisted of 30% small, 50% medium, 20% large gravel. Mass content of gravel designed varied from 0 to 30%. Mobile hydraulic steel tank with the size of 5m×1m×0.6m （length×width×height） was applied for holding test material. Test slope was adjusted to 25~ according to construction requirement of standard experimental plot. The results showed that： 1） Flow velocity on soil-rock deposition slope was higher with a maximum amplification of 52.8% during 0-6 min due to the positive effect of gravel on confluence compared to the bare. Whereas it was lower with a maximum damping of 408.5% when rill erosion dominated on the slope because of inhabita

关 键 词：水动力学 径流 侵蚀 工程堆积体 风沙区 砾石质量分数 径流含沙量 土壤剥蚀率 

分 类 号：S157.1[农业科学—土壤学]