1973 年 15 巻 1 号 p. 9-19
The chemical analysis has two practical purposes; one is the examinaton of water for drinking, agricultural and industrial uses the other is the interpretation of waterquality for fhe development and managenent of groundwater. Of the two the latter is needed to determine the major dissolved constituents in water.
Electrical conductivity, the reciprocal of specific resistance, has been used for estimating the concentration of total dissolved salts in water. In this paper the method of estimation is proposed taking consideration to the variations of concentration and composition in water samples. A first of “ diluted conductivity (DEC)” is obtained by the equation DEC. EC" in-which the electrical conductivity of water (EC) is expressed in micromhos/cm. The first estimate is then correlated with the concentration of total ions (T epm) by the following equation T. (DEC+ 25.3 Alk. )/111 in which Alk. is alkalinity of the sample expressed in epm. The ratios of estimated value from analytical one range from 91 to 109%, and the mean value and standard deviation of them is 100.55% and 3.77% respectively. Owing to the simplicity of conductity measurement, the method has many practical uses as follows; (1) checking of the correctness of analysis, (2) estimatien of the concentration of unknown ion or group of ions, from totol ions, (3) classification of hydrochemical facies.