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反演法确定田间尺度水分运动参数的研究(( 王仰仁， 李炎， 金建华， 韩娜娜 （天津农学院 水利工程系，天津 300384） 摘 要：在广泛开展的灌溉试验过程中，积累了大量的田间土壤含水率测试数据，充分利用这些资料，运用参数反演法求取或者改善土壤水分运动参数，对于土壤墒情的监测预报和农田水循环研究具有重要意义。本文以天津农学院农田水循环试验基地2009年度冬小麦返青到收获期实测的土壤含水率为依据，以土壤含水率模拟值与实测值相对误差平方和最小化为目标函数，以文献中获取的土壤水分运动参数变化范围为约束条件，建立了参数反演模型，采用内点法求得了适合于该试验基地土壤特性的水分运动参数。研究结果表明，参数反演可明显提高田间土壤水分模拟精度，合理选择优化初始值和步长缩放因子有助于改善参数的优化结果，比较以相对值误差平方和最小化目标函数和以绝对值误差平方和最小化目标函数，前者可以提高表层土壤含水率模拟精度。 关键词：土壤水分；参数反演；优化计算；冬小麦 中图分类号：P641.131；S152.72 文献标识码：A Study on Inversion of Field Water Movement Parameters WANG Yang-ren, LI Yan, JIN Jian- hua, HAN Na-na （Department of Hydraulic Engineering, Tianjin Agricultural University, Tianjin 300384, China） Abstract: During many irrigation experiments, the field soil moisture data are accumulated. The soil water movement parameters could be acquired or improved by inversion methods through using these datas. There is of great significance in monitoring and forecasting soil moisture and study on field water cycle. In this paper, according to the measured soil moisture of 2009 winter wheat from reviving to harvest at the Tianjin agricultural university field water cycle test base, the objective function is established with the minimum of the relative error square sum between the simulated and measured value of the soil moisture content. The constraint is the diversification range of the water movement parameters acquired from the documents. The parameter inversion model is established. The water transport parameters of this test base on soil characteristics are acquired by use of the interior point method. The research result shows that the simulation accuracy of the field soil moisture is significantly improved by the parameter inversion. Key words: soil moisture; parameter inversion; optimization calculation; winter wheat 非饱和土壤导水率和扩散率是利用土壤水动力学方法描述田间土壤剖面含水率随时间变化过程的两个重要土壤水分运动参数，可采用田间测试方法和室内测试方法确定，其中田间测试方法简单易行，但是所能测定的吸力范围较小[1]，所给出的参数变化范围有限，且测定时间较长。因而，实际操作过程中通常采用