土壤结构与田间持水率间的定量关系研究

对山西省晋中盆地9种不同质地土壤干密度和田间持水率的测定进行了同步系列试验,揭示了田间持水率随土壤干密度的变化过程及其特性,建立了田间持水率与土壤干密度之间的定量关系。试验结果表明,不同质地土壤的田间持水率都随土壤干密度的变化而变化,随着土壤干密度的增大,田间持水率经历从小到大,一直达到某一极限值,而后随土壤干密度的进一步增大而减小的变化过程;不同质地土壤具有不同的田间持水率极限值,田间持水率的极限值在孔隙度为42%～46%范围内时出现。田间持水率与土壤干密度的之间较好地符合二次多项式函数关系,采用二次多项式函数关系,通过土壤干密度实现对田间持水率的预测可以获得满意的结果。

The Quantitative Relationship between Soil Structure and Field Moisture Capacity

On the basis of Based on series of synchronous test data of soil bulk density and field moisture capacity of nine kinds of soils that were taken from Jinzhong basin in Shanxi province,the change characteristics of field moisture capacity with soil bulk density ware revealed,and the quantitative relationship between field moisture capacity and soil bulk density was established.The results show that the field moisture capacity of different soil texture changed with the soil bulk density.With increasing soil bulk density,the field moisture capacity increased gradually.reached maximum,then decreased.The maximum of field moisture for different soil texture was different,and the maximum of field moisture capacity occurred when the porosity changed from 42 percent to 46 percent.There was a close quadratic polynomial function relationship between field moisture capacity and soil bulk density,and a satisfactory result was achieved through the quadratic function to predict field moisture capacity by soil bulk density.