地中蒸渗计与自然潜水水分运移机理差异及误差分析

The Differences of The Mechanism of Water Movement Between Lysimeter And Natural Phreatic Water Situation And The Analysis of Errors of Them

本文对地中蒸渗计与自然潜水水分运移机理存在的差异及误差进行了分析。分析结果表明:利用地中蒸渗计监测的潜水蒸发量、降雨入渗补给量与自然潜水的实际情况存在一定的误差,这种误差随着潜水埋深的变化而变化,潜水埋深越浅,误差越大,因此,使用地中蒸渗计资料,特别对于潜水埋深小于1.5m的浅埋深地中蒸渗计资料时,一定要对蒸渗计资料作适当的技术处理,否则,如果直接引用,将会给计算成果带来较大的误差。

In this paper,the difference of the mechanism of water movement between lysimeter and natural phreatic water and the errors of them are analyzed. The analytic result indicated:There are differences between the amount of evaporation of phreatic water and the amount of percolation of rain measured by lysmeters and the real situation of natural phreatic water. These differences will vary along with the water-table fluctuation.The shallower the phreatic water table is ,the more obvious will be the errors. Consequently,when using the information of lysimeter,especially using the information of the lysimeters that are embedded in the depth that is less than 1.5m,some indispensable modifications should be done. Otherwise more obvious errors might appear in the results of calculation.