应用TDR对土壤含水率及土壤冻结融解深的计测

运用 TDR(Time Domain Reflectometry)计测土壤含水量 ,80年代以来就受到了瞩目 ,到今天为止TDR方法在土壤盐分浓度 ,浸润面深度 ,冻结融解面深度等许多领域得到广泛应用。为了确认在运用 TDR方法进行土壤含水率测定时介电常数 ε与含水率 θ之间的关系曲线的滞后现象的有无 ,以及确认运用 TDR方法计测土壤冻结融解面深度的有效性 ,进行了一系列的实验。实验证明 ,在运用 TDR方法进行土壤含水率测定时介电常数ε与含水率θ之间的标定曲线中没有出现滞后现象 ,运用 TDR方法计测土壤冻结融解面深度不论在室内实验还是在田间实验中都很有效 ,并取得了较高的精度。

Measuring Water Content and Frozen-unfrozen Interface in Soil with TDR

Since 1980's soil water content measurement with TDR (Time Domain Reflectometry) method has been attracting much attention worldwide. Until today it has been used extensively in the determination of soil salinity concentration, the penetration of wet front in soil, the location of frozen unfrozen interface in soil profile, etc. In order to confirm whether the hysteresis of the relationship between dielectric constant and soil water content exists or not, and to check the validity of TDR in locating the frozen unfrozen interface in soil profile, a series of experiments were conducted. The results indicated that the hysteresis phenomenon did not appear, and the TDR method in locating the frozen unfrozen interface in soil showed a high precision.