沟灌过程中土壤水分入渗参数与糙率的推求和验证

Calculation and verification of infiltration parameters and roughness in furrow irrigation

为了推求沟灌条件下土壤水分入渗参数,基于水量平衡法利用室内沟灌平台试验推求验证沟灌运动过程中水分入渗量以及水分入渗函数Kostiakov或修正的Kostiakov的参数,在两种不同糙率和排水边界条件下,运用水流推进阶段以及推进后阶段的实测数据如流入量、水流前峰推进函数、水深以及流出量等,建立了计算函数,并将其计算的入渗参数代入地表水流运动模型SRFR中验证水流推进过程以及不同测点的水深过程线,结果表明模拟值与实测值较为吻合。说明利用水量平衡法建立的土壤水分入渗参数可以准确的表达土壤水分入渗规律。

To determine soil water infiltration parameter under the condition of furrow irrigation, on the base of the volume balance approach, the indoor furrow experiment platform was used to estimate and verify the infiltration amount, the Kostiakov parameter and the modified one. Moreover, under the conditions of two different roughness and drainage boundaries, the measurement data of the irrigation advance stages and the latter stage, such as inflow, flow advance function, water depth and outflow, was applied to establish the calculation model. Additionally, the infiltration parameter determined by calculation was substituted into SRFR to verify water advance process and the water depth hydrographs of different measuring points, and simulated value had a good fit to the measured. Finally, the results show that soil water infiltration parameter based on the volume balance approach can be used to show the rule of soil water infiltration and guide the real time control of furrow irrigation.