Seasonal variations in Phytoplankton, Chlorophyll and NPK content in the Ganga River in Bihar
DOI:
https://doi.org/10.53550/ijsc.v53.i1.187Keywords:
Eutrophication, Phytoplankton Density, River ecosystem, Seasonal hydrologyAbstract
This study investigates the seasonal dynamics of the ganga river in bihar, focusing on changes in phytoplankton density, chlorophyll-a concentration, and nutrient levels (potassium, phosphorus, and nitrogen) during the pre- and post-monsoon periods. Water samples were collected from three locations, and standard analytical methods were used. The results show a significant decrease in phytoplankton density and chlorophyll-a levels after the monsoon, which was linked to nutrient washout from monsoonal floods. Post-monsoon, nitrogen levels increased, likely from agricultural runoff, while potassium levels decreased due to dilution. Phosphorus levels showed minimal change, suggesting adsorption onto sediments. Correlation analysis revealed strong nutrient-phytoplankton interactions prior to the onset of the monsoon, particularly highlighting the role of nitrogen in primary productivity. After the monsoon, these correlations weakened, indicating disruptions in the dynamics of nutrient cycling. These findings emphasize the role of seasonal hydrological processes in shaping river ecosystems and highlight the need for sustainable management practices to mitigate eutrophication and preserve ecological balance.
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