天津滨海地区土壤含盐量与电导率的关系

目的]建立天津滨海盐渍区（以Na＋-Cl-为主类型）土壤含盐量与电导率之间的换算关系。方法]采用烘干残渣法测定土壤含盐量,并与电导率公式求算的土壤含盐量进行比较,以验证建立的关系式是否有效。结果]测定土壤浸提液电导率具有操作简单、快速、准确的特点,在一定盐度范围内,电导率与含盐量呈直线相关关系。经测定分析,天津滨海盐渍区电导率与含盐量的回归关系式为：y（%）=0.0033EC5∶1-0.6736,r=0.9917,达到极显著水平;实证检验结果表明,公式求算与烘干残渣法的平均误差为3.88%,满足生产实践的精度要求。通过对滨海盐渍区（Na＋-Cl-类型）其他经验公式的对比分析,发现该关系式对整个环渤海盐渍区均有较高的实用价值。结论]当土壤含盐量超过1.6%或2.0%时,建议仍以烘干残渣法测定为好。

Research on the Relationship between the Content of Salt in Soil and the Electric Conductivity in Coastal Area of Tianjin

Objective] The conversion method between the salinity in he Tianjin Binhai saline area soil(Na+-Cl-type) and the electrical conductivity was established.Method] The content of salt soil was determined with the method of dried residue and the result was compared with the salinity calculated with the formula of electrical conductivity to verify the validity of their relationship.Results] The method of measurement of the conductivity of soil extracts was simple,fast and accurate.In a certain range of salinity in soil,there was a linear relationship between the conductivity and salinity.The measurement and analysis indicated that the regression formula of the conductivity and salinity in the Tianjin coastal saline zone was:y (%)=0.003 3EC5:1-0.673 6,and the tested result r=0.991 7,with a significant level.And also,the empirically testing results showed that the average error between the formula calculation and dried residue method was 3.88%,which met the requirement of precision in practical production.Through the comparison with other empirical formula and analysis,the application of the method was with high practical value in Bohai Sea saline are Conclusion] When the salinity in soil exceeded 1.6% or 2.0%,it was proposed the method of dried residue in evaluation of salinity would be much better.