Abstract
Chilika Lake, located on East coast of Odisha (19. 8450° N, 85. 4788° E), India, experiences dynamic physicochemical variations due to inputs from rivulets as well as seawater influx, making it brackish, which supports a gargantuan load of flora and fauna. The current report explored variations in water quality across three seasons, summer, winter and rainy across 10 geographically distinct lake zones, using spatial mapping with QGIS (Quantum Geographic Information System) and ArcGIS (Arc Geographic Information System) and additionally through microbial profiling via VITEK-2, covering approximately 35 km of its coastline. Ten distinct locations within the lake, including Mangaljodi, Balugaon, Kalijai, Barkul, Rambha and Satapada yielded water samples to analyze the biological balance and water quality of Chilika. The following parameters were mainly examined: fluoride, sodium chloride, ammonium, hydrogen sulfide, heavy metals (Fe, Cu, Pb, Mn, Hg and Zn), sulfates, chlorides, nitrates, nitrites, pH, alkalinity and overall hardness. Oneway ANOVA was used to identify significant seasonal variations (p < 0.05) in core indicators, such as nitrate, fluoride, ammonium and lead, highlighting anthropogenic inputs and storm-induced runoffs. The pH was >7, but the salinity levels varied at 1,000-2,000 ppm. Several Gram-positive bacterial isolates, Staphylococcus xylosus and Staphylococcus gallinarum suggested potential bacterial contaminations to humans and animals. The emergence of antibiotic resistance in the lake and the management of fisheries and tourism sustainably were crucial for the conduct of routine biogeochemical monitoring. Results illustrate how human pressures; pollution inputs and freshwater flow impact the aquatic health of Chilika.
Keywords: Bacterial Pollution, Brackish Ecosystem, Chilika Lake, Heavy Metals, Physicochemical Parameters.