Ecological Health Evaluation of Ziarat River Using Water Quality Index, Golestan Province, Iran

摘要

Due to decreasing water quality of the Ziarat River, which is one of the most important rivers for drinking water in Gorgan, it is necessary to manage this river. The purpose of this study was to evaluate the ecological health of the Ziarat River of Golestan province via the Water Quality Index (WQI) qualitative index. For this purpose, 6 sampling stations were selected along the Ziarat River, and samples were taken from April to August of 2014 every 45 days at sampling stations. The parameters of dissolved oxygen, nitrate, nitrite and phage were measured at each turn and the data were analyzed by WQI qualitative index and SPSS 21 software. The results showed that water quality of the Ziarat River was relatively good during the spring and summer. Also, the results showed that there was a significant correlation between nitrite and positive qualitative index (with increasing amount of nitrite the numerical value of the qualitative index also increases, which indicates a decrease in water quality). Between the dissolved oxygen and the numerical value of the negative quality correlation index (with increasing amount of solution oxidant, the numerical value of the qualitative reduction index, which indicates the increase of water quality).