摘要
为深入揭示植被覆盖下坡面流阻力的内在规律,在考虑植被段前壅高和段后水深的基础上,系统研究了植被茎秆覆盖度为32.32%时6个坡度和12个流量组合下坡面流的流动特性。结果表明:在植被茎秆覆盖度为32.32%条件下,当坡度小于6°时,坡度对平均流速影响与流量相当,而坡度大于6°时,坡度对流速的影响甚微;试验过程中,壅水区水深与平均水深均随着流量增加而增大,而尾水深则略有波动;植被阻力系数随雷诺数的增加而增大,而随弗汝徳数的增加而减小,这是植被的粘滞阻力和压差阻力相互作用的结果。该成果为进一步研究植被覆盖下坡面流水动力学特性提供理论依据,进而对水土流失治理及生态修复均具有一定的指导意义。
Hydraulic dynamic characteristics of the overland flow under the vegetation stem are studied by experiments,considering the flow depth before or in the back of vegetation,with stem coverage 32%,12 discharges and 6 slope gradients. Based on the physical experiments,the following results are founded. The slope causes a great influence on average flow velocity when the slope degree is less than 6; however,the effect of the overland flow on the slope can be ignored when slope is steeper than 6. Depth of the water before vegetation and average depth will increase with the flow discharge; Depth in the back of vegetation fluctuated. Resistance coefficients increase as Reynolds number increase,but decrease as the Froude Number increase; The results are caused by interaction of viscous resistance and pressure drag. The results supply some bases in studying the hydraulic dynamic characteristics of the overland flow under the vegetation stem coverage,which might help to understand water loss and soil erosion control and ecological restoration.
出处
《泥沙研究》
CSCD
北大核心
2016年第4期22-27,共6页
Journal of Sediment Research
基金
国家自然科学基金资助项目(51579214)
中央高校基本科研业务费专项(Z109021564)
黄土高原土壤侵蚀与旱地农业国家重点实验室主任基金项目(A314021402-1619)
流域水循环模拟与调控国家重点实验室开放基金项目(IWHR-SKL-2014)
关键词
坡面流
植被茎秆
水动力学特性
overland flow
vegetation stem
hydraulic characteristic
作者简介
杨帆（1991-），女，吉林白城人，硕士研究生，主要从事水土保持及植被水流方面的研究。E-mail：yangfatn199126@163．com
通讯作者：张宽地。E-mail：zhangkuandi428@126．com
