Investigating the quality of groundwater used in raising of rainbow trout in Mazandaran plain

Mazandaran Plain has an acceptable position in terms of water resources. The existence of numerous fish breeding centers with significant consumption of groundwater in this industry, optimal and continuous monitoring of the quality of water used in this industry is considered a necessity. In this study, in 2019, water samples were taken from 150 observation wells in the Mazandaran plain, which were the closest wells to the cold water fish farms, and the samples were compared with the national cold water fish water quality standards of Iran and some foreign countries. Also, the amount of discharge consumed in the fish breeding centers of the region was checked. Total hardness, electrical conductivity and pH were within the national standard range, but nitrate and dissolved solids were outside the appropriate national standard range. Comparison of the RMSE of kriging, multidimensional linear gradient and IDW methods revealed that the IDW method is better than other methods for the quality of groundwater in the Mazandaran Plain. From the comparison of the recorded values ​​of the parameters with the standards, it was found that the quality of the parameters had an increasing trend from the west to the east of the Mazandaran plain, and a decreasing trend from the north to the south. In general, the water quality of Mazandaran plain is more suitable for the development of fish breeding centers in the central and western regions.