利用土壤介电性质间接确定土壤体积含水量的方法已广泛应用于相关的学科领域。本研究通过土柱试验,针对我国潮土、风沙土、红壤、水稻土等4种典型土壤,对8种质地土壤介电常数与体积含水量的经验关系展开了研究,修正了Topp(1980)关系式,并确定了Herkelrath关系式校正参数a、b值。结果表明,Topp(1980)关系式对砂壤性潮土、粉砂质黏性潮土、风沙土、黏性红壤含水量的预测误差较大;Topp拟合关系式虽然对Topp(1980)关系式有所优化,但效果仍然不甚理想,在含水量的不同范围有时误差较大,特别是对黏性红壤含水量的预测效果较差;Herkelrath拟合关系式对试验的4种类型土壤含水量的预测效果均较好,可以作为相关应用的优先选择;三种关系式对两种质地的水稻土含水量均有很好的预测效果,平均绝对误差小于0.03cm^3cm^-3
The use of soil dielectric properties as an indirect measurement of volumetric moisture content is accepted in a wide range of disciplines. Empirical relationship was studied between soil dielectric constant and volumetric water content in eight soils of four types, i. e.. fluvo-aquci soil, aeolian sandy soil, red soil, and paddy soil. Based on soil column experiments, the Topp's equation (1980) was amended, and correction factors a and b of the Herkelrath (1991) equation were verified. Results show that the prediction of soil volumetric moisture content using the Topp's equation was relatively big in error for sandy loam fluvo-aquci soil, silty clay fluvo-aquci soil, aeolian sandy soil, and clay red soil. Compared with thr Topp's equation (1980) , the Topp fitting equation was optimized, but its effect was not satisfactory with errors being still quite big in predicting volumetric moisture contents various in range, especially for clay red soil. The Herkelrath fitting equation was relatively better for all the four types of soils, and could be cited as the first priority choice for application. All the three relationship equations were quite good in predicting volumetric moisture content in the two paddy soils different in texture, with the mean absolute error being less than 0.03 em^3 cm^-3