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用压力膜仪测定土壤水分特征曲线，田间实地观察不同深度土壤水吸力变化动态和覆盖种麦条件下的水吸力变化。结果表明，徐淮黄潮土地区水分供应特性受大气降水和蒸散所制约；水分供应年动态可分为春季干旱期、夏季过湿期、秋季蒸发期和冬季冻结期等４个时期；水分动态变化由底土到表土加快；覆盖种麦条件下土壤水吸力的变化与对照相比，表现为前低、中高、后平的特点，反映了覆盖种麦的节水效果主要在小麦生长前期。
The soil moisture characteristic curve was measured with a pressure meter. The changes of soil water suction at different depths and the changes of water suction under the conditions of covering wheat were observed in the field. The results showed that the water supply characteristics in the Xuhuai yellow soil region were restricted by the precipitation and evapotranspiration. The annual dynamic of water supply could be divided into four periods: spring drought period, summer over wet period, autumn evaporation period and winter freezing period. Compared with the control, the changes of soil water suction under the conditions of covering wheat were the characteristics of low before, middle and high after the change, which reflected that the water-saving effect of covering wheat was mainly in the early stage of wheat growth.