Water quality assessment using WQI and zooplankton indicators in aquatic ecosystems: Insights from a correlation-based study

Since rivers provide freshwater to all rural and urban communities, it is necessary but difficult to monitor the river water quality. The goal of this study was to assess how water-quality parameters relate to zooplankton communities. Water samples were collected from five different locations along the main streams of the Kangsabati River, West Medinipur. Analysed twelve common water quality indicators, including pH, temperature (temp.), dissolve oxygen (DO), secchi depth (SD), salinity (Sal), biological oxygen demand (BOD), electrical conductivity (EC), total dissolve solid (TDS), hardness (Hard), Alkalinity (Alk), total nitrogen (TN), total phosphorous (TP) and plankton density (PD) to assess the water quality index (WQI). The WQI model was employed to determine water quality (WQ) status, while two-tailed Pearson’s correlation and multivariate PCA analysis assessed relationship between the PD and WQ. 57 zooplankton species were found, including copepods (49.12 %), cladocera (17.54 %), and rotifers (33.33 %). The WQI value ranged from 87.68–125.88, indicating very poor to unfit for consumption water quality. Strong correlation among PD, BOD, and DO, was observed by multivariate analysis. As a result, the zooplankton index should only be used with expertise to indicate water quality. In order to promote sustainable community growth, findings of present investigation may be useful in preserving the complex aquatic ecosystem.