天津滨海地区3种典型土壤水分物理特性

Moisture-physical characteristics of three types of soils in Tianjin Binhai area

采用压力膜仪法测定滨海地区盐渍土、吹填土和种植土3种典型土壤水分特征曲线,并用VG模型进行参数求解与曲线拟合.结果表明：VG模型能够较好地拟合天津滨海地区3种典型土壤的水分特征曲线,残差平方和较小.低吸力阶段,吹填土含水量最高,下降速度最快;高吸力阶段,吹填土的含水量介于盐渍土和种植土之间.心土层（20~40 cm）、底土层（40~60 cm）以及吹填土的土壤含水量高但有效性低.

The moisture characteristics of three typical soils,saline soil,dredger fill soil and planting soil,were measured with the pressure membrane method in the Tianjin Binhai area.The parameters were calculated and the fitting curves were obtained using the VG mode.The results show that the VG model can fit the moisture characteristic curve of the three typical soils with a smaller residual sum of squares.At low suctions,dredger fill soil has the maximum water content and the fastest rate of decline;at high suctions,the water content of dredger fill is between those of the saline soil and planting soil.Although there is high soil water content in the subsoil layer at a depth of 20 cm to 40 cm,in the bottom layer at a depth of 40 cm to 60 cm,and dredger fill,the water availability and utilization rate are lower.