暴雨条件下横垄坡面产汇流特征及其对微地形变化的响应OA
Runoff generation and confluence characteristics on cross-slopes with ridge tillage under rainstorm conditions and their response to microtopographic variations
[目的]地表微地形变化势必会影响坡面产汇流特征,弄清横坡垄作坡面产汇流特征及其与微地形变化间关系,为区域水土流失有效防控提供支撑.[方法]采用室内人工模拟降雨方法,立足于微地形角度,开展降雨条件下不同垄高(5,10,15 cm)、垄距(50,70,90 cm)的横垄坡面微地形变化与产汇流特征研究,明晰不同坡面产汇流对微地形变化的响应.[结果](1)各横垄坡面地表糙度总体随垄高(H)和垄距(L)的增加而增加,且受垄高(r=0.92,p<0.01)的影响远大于垄距(r=0.14);(2)结构水文连通性随距高比(L/H)减小而减小,功能水文连通性则在L/H为4.7～5.0区间的横垄坡面较低,水文连通面积比率较均值减少37.95%;(3)初始产流时间随L/H先增大后减小,中密垄(5.0 L/H)坡面初始产流时间最长(40 min);各坡面汇流型态以平行状为主,汇流网络均具有明显单分形特征,其复杂性和自相似性与L/H呈显著正相关;(4)地表微地形对汇流和产流特征的直接效应值分别为 0.871(p<0.01)和-0.711(p>0.05),通过直接影响汇流过程进而间接影响坡面产流.[结论]研究区L/H在4.7～5.0区间的横垄坡面调控坡面产汇流效应最佳,研究结果有助于坡面横垄合理布设与区域水土流失有效防控.
[Objective]Surface microtopographic variations inevitably affect the characteristics of slope runoff generation and confluence.Clarifying the characteristics of runoff generation and confluence on cross-slopes with ridge tillage and their relationship with microtopographic variations provides support for the effective prevention and control of regional soil and water loss.[Methods]An indoor artificial rainfall simulation method was used to study microtopographic variations and the runoff generation and confluence characteristics of cross-slopes with ridge tillage under different ridge heights(5,10,15 cm)and ridge distances(50,70,90 cm).The responses of runoff generation and confluence on different slopes to microtopographic variations were analyzed.[Results](1)The surface roughness of each slope increased with increasing ridge height(H)and ridge distance(L),and the effect of ridge height(r=0.92,p<0.01)was much greater than that of ridge distance(r=0.14).(2)Structural hydrological connectivity decreased as the ratio of ridge distance to height(L/H)decreased,while functional hydrological connectivity was lower on cross-slopes with L/H values ranging from 4.7 to 5.0,and the hydrologically connected area ratio decreased by 37.95%compared with the average.(3)The initial runoff generation time first increased and then decreased with L/H,reaching the longest duration(40 min)on the slope with medium-dense ridge(5.0 L/H).The runoff confluence patterns on each slope were mainly parallel,and the confluence networks exhibited distinct mono-fractal evolution characteristics.Both the complexity and self-similarity of these networks were significantly positively correlated with L/H.(4)The direct effect values of surface microtopography on runoff confluence and generation were 0.871(p<0.01)and-0.711(p>0.05),respectively,and microtopographic variations indirectly affected slope runoff generation by directly influencing the confluence process.[Conclusion]In the study area,cross-slopes with ridge tillage and L/H values between 4.7～5.0 demonstrate the optimal regulation of slope runoff generation and confluence.These findings are helpful for the rational layout of cross-slopes with ridge tillage and effective prevention and control of regional soil and water loss.
Ke Xianze;Yang Yan;Zheng Zicheng;Wang Nana
College of Resources,Sichuan Agricultural University,Chengdu 611130,ChinaSichuan Water Conservancy Planning and Research Institute,Chengdu 610072,ChinaCollege of Resources,Sichuan Agricultural University,Chengdu 611130,ChinaCollege of Resources,Sichuan Agricultural University,Chengdu 611130,China
农业科技
横垄坡面微地形变化产流过程水文连通性汇流网络
cross-slopes with ridge tillagemicrotopographic variationsrunoff generation processhydrological connectivityconfluence network
《水土保持研究》 2026 (1)
29-38,45,11
国家自然科学基金项目"紫色土坡面地表微地形变化与水沙过程的耦合机制"(42177316)
评论