摘要
【目的】对陕北榆林黄土坡地枣园的降雨入渗、产流进行试验与模拟研究,为陕北坡地枣园雨水的高效利用提供指导。【方法】在陕北枣园径流小区,利用人工降雨试验,开展不同降雨强度(0.8,1.0,1.3mm/min)和不同初始土壤含水率(0.08,0.15,0.24cm3/cm3)条件下的降雨、入渗产流试验,运用Richards入渗方程结合水量平衡方程对人工降雨的入渗、产流过程进行模拟。【结果】土壤含水率相同条件下,降雨强度越大产流时刻越早,入渗达到稳定的时间越短,累积入渗量和径流量越大;降雨强度相同条件下,土壤初始含水率越大,产流越快,平均入渗率越小,趋于稳定入渗的时间越短,累积产流量也越大。模拟值与实测值相比,累积入渗量相对误差小于3%,平方根误差小于0.3mm;累积径流量平均误差≤12.5%,平方根误差小于0.4mm。模拟产流起始时刻普遍滞后于实测产流时刻,滞后时间最少为0.8min,最多为2.55min,其原因与坡面饱和导水率的空间变异性及降雨的不均匀性有关。【结论】采用Richards入渗方程并结合水量平衡方程模拟黄土坡地径流小区的降雨入渗、产流过程,结果合理可靠,且比较符合实际,但产流起始时间的模拟还需进一步探索。
【Objective】This paper studied the infiltration and runoff under field to improve the efficient use of rainwater in Jujube orchard in Northern Shaanxi.【Method】The paper carried out runoff infiltration test in Jujube runoff plots in Northern Shaanxi under artificial rainfalls with different intensities(0.8,1.0,and 1.3mm/min)and initial soil moistures(0.08,0.15,and 0.24cm3/cm3).The infiltration and runoff formation on slope land was simulated with Richards equation and water balance equation.【Result】With same soil moisture,greater rainfall intensity had sooner runoff moment,shorter time to stable infiltration,and larger cumulative infiltration and runoff.With same rainfall intensity,greater the initial soil moisture content had faster flow,smaller average infiltration rate,shorter time to stable infiltration,and larger cumulative runoff.The mean relative error of period cumulative infiltration was less than 3%,and the rootmean squared error(RSME)was less than 0.3mm.The mean relative error of period cumulative runoff was less than 12.5%,and the RSME was less than 0.4mm.Simulated runoff was generally later than the measured time with a lag time of 0.8min to 2.55 min,which was related to the inhomogeneity of slope saturated hydraulic conductivity and spatial variability of rainfall.【Conclusion】The simulation results were reasonable and reliable,but the simulation of starting time of runoff needs further exploration.
出处
《西北农林科技大学学报（自然科学版）》
CSCD
北大核心
2014年第11期163-168,共6页
Journal of Northwest A&F University(Natural Science Edition)
基金
国家自然科学基金项目(51239009
41171034)
陕西省自然科学基金(重点)项目(2013JZ012)
关键词
枣园
黄土坡地
入渗产流模拟
人工降雨
陕北
jujube orchard
Loess slope land
infiltration and runoff simulation
artificial rainfall
Northern Shaanxi
