Spatial variation and environmental risk of hazardous industrial effluents in the Gomezpuram Water Channel, Gulf of Mannar, India

Abstract

This study investigated the Gomezpuram Water Channel in the Gulf of Mannar, India, for the first time regarding spatial variations in water quality. Standard methods were adopted to evaluate water samples collected between October and November 2022. Due to the manifestation of hypersaline algae (Dunaliella sp.), the water channel has turned pink, indicating a considerable effluent discharge from different untreated salt pans and seafood processing plants. Green a lgae Dunaliella salina (OR772295), Dunaliella pseudosalina (OR772296), and Dunaliella tertiolecta (OR772297) were identified and confirmed through molecular characterization in the water channel for the first time. The present investigation's Water Quality Index (WQI) shows that the coastal water channel was poorly monitored, managed, and unsuitable for human consumption. A box plot compares all parameters across sampling sites to comprehend environmental data's spatial variation and distribution. Pearson's correlation shows strong positive correlations between related variables, such as TSS and TDS, and pigment concentration, indicating that these parameters increase or decrease together. A Two-way hierarchical analysis visually represents those stations 3, 4, and 5 exhibit similar water quality profiles, whereas station 1 shows distinct characteristics, likely due to localized pollution. This study provides helpful information for management purposes by illustrating the spatial differences in the water quality condition and the anthropogenic sources causing water discoloration in this water channel.