文章摘要
闫帅旗, 刘俊娥, 周正朝, 边熇, 朱冰冰.坡面不同植被覆盖格局下的水文连通性变化特征[J].水土保持学报,2021,35(6):228~234,242
坡面不同植被覆盖格局下的水文连通性变化特征
Variation Characteristics of Hydrological Connectivity Under Different Slope Cover Patterns
投稿时间:2021-06-17  
DOI:10.13870/j.cnki.stbcxb.2021.06.031
中文关键词: 坡面  植被格局  侵蚀  水文连通性
英文关键词: slope  vegetation cover patterns  erosion  hydrological connectivity
基金项目:陕西省重点研发计划项目"沙漠—黄土过渡带植被结构特征阈值与提质增效关键技术研究"(2021ZDLSF05-02);国家自然科学基金项目"黄土区退耕坡面植被恢复对坡沟系统侵蚀产沙的阻控研究"(41601285);国家自然科学基金项目"黄土高原水蚀风蚀交错区细沟水流分离-输沙过程模拟"(42077058)
作者单位E-mail
闫帅旗, 刘俊娥, 周正朝, 边熇, 朱冰冰 陕西师范大学地理科学与旅游学院, 西安 710119 zbb1026@126.com 
摘要点击次数: 156
全文下载次数: 172
中文摘要:
      为深入探索不同植被盖度及其格局在不同冲刷流量下的坡面侵蚀过程机理,利用野外人工冲刷试验,以自然恢复草本植被小盖度格局、坡上相对聚集格局、坡中相对聚集格局、坡下相对聚集格局和较大盖度格局为研究对象,通过引入水流路径长度和水流阻抗指数,分析了不同植被盖度及格局对坡面侵蚀和水文连通性的影响作用。结果表明:(1)植被盖度及格局可影响坡面的侵蚀状况。坡面植被盖度为13.5%的产流产沙量分别是盖度为34.0%坡面对应值的2.36,3.02倍;同时与坡上和坡中相对聚集格局相比,坡下相对聚集格局的坡面产流产沙量最多,其中产流量分别增加16.42%和8.00%,产沙量分别增加26.53%和23.56%。但随着冲刷流量的增加,不同植被盖度和覆盖位置下的坡面产流产沙量差距减小。(2)植被盖度与水流路径长度和水流阻抗指数间均存在显著的线性关系。同时水流路径长度在不同覆盖格局下存在差异,其中坡上相对聚集格局的水流路径长度分别比坡中和坡下相对聚集格局减少10.89%和18.33%。而水流阻抗指数在不同覆盖格局下表示意义不明确,但可灵活反映不同试验条件下的水文连通性变化。(3)坡面产流产沙量随水流路径长度和水流阻抗指数增加呈显著的指数变化趋势。水流路径长度和水流阻抗指数均可作为反映坡面侵蚀过程及其机理的参数之一。该研究成果对于深入理解坡面侵蚀过程机理及定量评价水文连通性与植被和坡面侵蚀的作用关系具有参考价值,从而为坡面侵蚀预测模型完善和地区生态环境建设提供评价依据。
英文摘要:
      Vegetation cover and its pattern generally determine the mechanisms in the runoff and sediment reduction under different flow rates. In this paper, the responses of sediment yield to the interaction effects of vegetation cover age and slope positions were revealed through field experiments, including the lowest coverage pattern, relatively concentrated distribution on the upper of the slope, relatively concentrated distribution on the middle of the slope, relatively concentrated distribution on the lower of the slope, and the highest coverage pattern. Then the relation between hydrodynamic connectivity of slope and soil erosion were analyzed by three kinds of hydrological connectivity indexes (FL, FLr, FLs). The results showed that: (1) Vegetation cover and its pattern are important factors affecting slope soil erosion process. The sediment yield of the slope with vegetation coverage of 13.5% was about 2.36 and 3.02 times of the slope with coverage of 34.0%, respectively. At the same time, compared with relatively concentrated distribution on the upper and middle of the slope, relatively concentrated distribution on the lower of the slope was mostly in the slope. The regulation functions on runoff and sediment with the grass strip relatively concentrated distribution on the lower part of the slope were generally worse. Among them, the runoff amount increased by 16.42% and 8.00%, respectively, and the sediment yield increased by 26.53% and 23.56%, respectively. However, with the increase of the flow rates, the gap between the yields of runoff and sediment in different vegetation coverage was reduced. (2) FL, FLr and FLs, the important indexes of hydrological connectivity, exhibited linear correlation relationship to vegetation coverage. Meanwhile at the condition of three kinds of grass strip positions, the difference of FL was obvious. Under the experimental conditions, compared with the relatively concentrated distribution on the middle and lower of the slope above, the FL on the relatively concentrated distribution on the upper slope were decreased by 10.89% and 18.33%, respectively. By the research, there was no significant covariability has been found between the FLr and FLs with vegetation patterns. But it could flexibly reflect the changes in hydrological connectivity under different test conditions. (3) There were significant correlations between the hydrological parameters and slope soil erosion. And the increase of FLr and FLs and the decrease of FL could cause an exponentially reduction in the amount of runoff yield and sediment production. Thus, FL, FLr, and FLs can be used to indicate the hydrodynamic parameters of slope surface water flow and sediment yield in the change. The results have reference value for deep understanding of slope erosion process and quantitative evaluation of hydrological connectivity and vegetation and slope erosion, providing evaluation of random erosion prediction model and regional ecological environment construction.
查看全文   查看/发表评论  下载PDF阅读器
关闭