摘要
地表径流是引起坡面土壤和养分流失的主要动力,寻求有效途径对降雨径流进行科学预测,是陕南地区农业面源污染防治的基础.本文选取后沟小流域8个不同坡度和面积的径流小区,结合2011-2012年汛期的6场降雨产流的实测数据,评价陕南地区坡耕地基于SCS-CN模型的适用性,并考虑降雨量影响的基础上对径流曲线数CN和初损系数Iα进行修正.结果表明,陕南地区小流域坡耕地初损参数λ为0.1-0.4.随着Iα的变化对CN进行修正,确定CN值为58.选取的8个径流小区中,利用SCS-CN模型的模拟效果较好,径流量模拟值变化趋势与实测值一致,降雨径流量模拟值与实测值进行相关分析,计算得到两者的相关性均达到极显著相关.6场降雨事件径流模拟值与实测值分别为8 082.3 L和7 419.8 L,相对误差为8.8%.该研究结果可为陕南地区降雨径流预测及面源污染防治提供参考.
Overland runoff is a main factor causing soil and nutrient loss on the slope cropland, so seeking a scientific and effective way to predict rainfall runoff is the base of agricultural non - point source pollution preven- tion and control in southern Shaanxi area. This paper selects the Hougou small catchment which has eight runoff plots with different slope gradients and size ,the measured data of 6 rainfalls in flood season of 2011 -2012 to eval- uate the applicability of the SCS - CN model on cultivated sloping land in southern Shaanxi while to correct the CN （ Runoff Curve Number） and Ia （ initial loss coefficient） based on the consideration of the influence of rainfall vol- ume. The results show that the A （ initial abstraction ratio） is 0. 1 ~ 0.4 in southern Shaanxi area. With the change of Is, the CN is modified and determined the CN value is 58. The results of 6 times simulated rainfall with SCS - CN model are good and the runoff simulation trend values and the measured values are basically the same in selected eight runoff plots. The correlation analysis between the simulated values and measured values of the 6 typical rainfalls is carried out, and the correlation between them is very significant. The total runoff of measured value and simulation value of 6 rainfall events is 7 419.8 L and 8 082.3L, respectively, the relative error is 8. 8%. This research results can provide references for the rainfall runoff forecast and non - point source pollution control in southern Shaanxi area.
出处
《绵阳师范学院学报》
2016年第11期84-90,共7页
Journal of Mianyang Teachers＇ College
基金
四川省教育厅项目(16ZB0311)
中国博士后科学基金项目(2014M562338)
绵阳师范学院博士科研启动项目(QD2014A002)
绵阳师范学院青年基金项目(2013B09)
关键词
SCS-CN模型
径流预测
初损系数
陕南地区
SCS -CN model, runoff forecast, initial abstraction ratio, southern Shaanxi area
