地下水浅埋条件下冬小麦和大豆土壤水分动态预报模型研究

DYNAMIC FORECASTING MODELS OF SOIL MOISTURE IN WINTER WHEAT AND SOYBEAN FIELDS IN SHALLOW GROUNDWATER LEVEL

用统计方法和水量平衡法推导出江淮地区潜水蒸发经验计算模型。利用农田水分平衡原理分别在江淮地区建立了引入潜水蒸发量和没有引入潜水蒸发量的冬小麦和大豆土壤水分动态预报模型 ,并对这两种模型在地下水浅埋条件下的预报准确度进行比较。 1 980年的比较结果是 :当预报时效为 1 0天时 ,两种作物 7个时段的土壤水分平均绝对误差前者为8.2mm ,后者为 2 0 .1mm ,平均相对误差分别为 2 .8%和 6.8%。引入潜水蒸发量后 。

The calculating model of phreatic water evaporation in the Jianghuai region is g iven by means of statistic and water balance methods. According to the water bal ance principles of crop fields, the dynamic forecasting models of soil moisture in winter wheat and soybean fields with phreatic water evaporation and without p hreatic water evaporation are built. The forecasting accuracy of the two models in a condition of shallow groundwater level is compared. The results in 1980 sho w that the mean absolute errors and mean relative errors of the former for seven periods of two crops are 8.2 mm and 2.8% and the mean absolute errors and mean relative errors of the latter for seven periods of two crops are 20.1 mm and 6.8 %. The forecasting accuracy of the dynamic forecasting models of soil moisture i n winter wheat and soybean fields including phreatic water evaporation is improv ed notably.