Water Science and Technology (Nov 2021)

Water quality assessment of East Kolkata Wetland with a special focus on bioremediation by nitrifying bacteria

  • Mousumi Saha,
  • Agniswar Sarkar,
  • Bidyut Bandyopadhyay

DOI
https://doi.org/10.2166/wst.2021.223
Journal volume & issue
Vol. 84, no. 10-11
pp. 2718 – 2736

Abstract

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East Kolkata Wetlands (EKW) is designated as International Ramsar site and are the hotspot for large-scale wastewater aquaculture practices. However, the continued surveillance of physicochemical properties of water and application of an eco-friendly approach are essential to ensure safe aquaculture practices. In the present study, we assessed the seasonal variation in physicochemical parameters of water across EKW and investigated the role of nitrifying bacteria as probiotics. We statistically analyzed various physicochemical properties of water samples from EKW. Results of the statistical analysis indicated a significant variation in all the physicochemical parameters across the selected water bodies of EKW (p < 0.01). We isolated and enumerated Nitrosomonas sp. and Nitrobacter sp. and assessed their ability to degrade trichloroethylene (TCE). The role of Nitrosomonas sp. and Nitrobacter sp. were further investigated and established through a small-scale experiment. Two microbial isolates, NSW3 and NBW2, displayed superior TCE degradation ability at pH 5, and the application of these strains as probiotics were found to improve the quality of water and survival rate of fishes in the treated experimental tanks. Our findings suggest that the application of the above mixed bacterial cultures in aquaculture could be an effective and environment-friendly approach for safe and productive aquaculture operations. HIGHLIGHTS East Kolkata Wetlands, an International Ramsar site and hotspot for aquaculture.; Statistical correlations of physicochemical parameters shown significant variation.; Standardized the role of nitrifying bacteria as probotics for aquaculture practices.; Trichloroethylene degradation by bacteria were analysed for reducing pollutants.; Establishment of bioremediation and bio-security protocol of wastewater management.;

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