田间土壤水分通量确定方法的研究

Soil water flux study in field

本文采用圭尔夫渗透仪(Guelph Permeameter)测定田间1m土层处饱和与非饱和导水率,用负压计测定相应处的吸力与水势梯度,来研究确定田间水分通量的方法。从实测得到的导水率、吸力、水势梯度等资料的统计特征值与自相关分析,表现出空间变异性的客观存在。因此,本文引入标定方法处理空间变异性和引入校正系数克服导水率的不均一性对通量的影响有不同权重的矛盾。作为一种研究方法,它较好地处理了田间土壤水分通量的定量化的问题,但在田间实测技术上尚待改进。

This paper presents a method of estimating soil water flux, while its hydraulic conductivity and suction at one meter depth are known. The former is measured by the Guelph permeameter, and the latter or the potential gradient is measured by tensiometer in situ. A statistical and correlational analysis of the field measurement data indicates that the spatial variation of these parameters is obvious. Therefore, scaling method is used to reduce variation problem and a modified coefficient is selected to enable the precise estimation of flux under different hydraulic conductivity.