Microbial Diversity, Physicochemical Parameters, and Heavy Metal Tolerance of Bacteria in the Hindon River: Ecological Assessment and Bioremediation Potential

AbstractThe Hindon River, a tributary of the Yamuna, is subject to pollution from industrial effluents,domestic sewage, and agricultural runoff. This study systematically assessed microbial diversity,physicochemical parameters, and heavy metal resistance of bacterial isolates from six sites (H1–H6) along the Saharanpur stretch of the river. Physicochemical analysis revealed significantspatial variations, with domestic discharge (H4) showing the highest TDS (1500 ± 40 mg/L),BOD (15.5 ± 0.7 mg/L), COD (81.2 ± 3.1 mg/L), and hardness (340 ± 12 mg/L), while upstream(H1) exhibited the lowest pollution load. Heavy metal concentrations (Pb, Cr, Cd, As, Ni) peakedat H2 and H4, confirming the influence of anthropogenic activities. Bacterial enumerationindicated higher CFU counts in polluted sites, with distinct colony morphologies suggestingecological adaptation. Notably, Pseudomonas putida (H101) and Bacillus subtilis (H102) fromthe upstream site (H1) demonstrated resistance to Cu2+ and Ni2+, but not Pb2+, highlighting theirpotential for bioremediation. These findings underscore the critical pollution hotspots in theHindon River and provide promising bacterial candidates for eco-restoration.