Biological Assessment of Major Water Bodies of The City of Kolkata
Keywords:Biomonitoring, Benthos, Water Quality, Pollution, Diversity
Benthic macroinvertebrate monitoring or biological monitoring is use of biological responses for populations and communities of certain indicator organisms to evaluate anthropogenic environmental changes. Biomonitoring is a special way of assessing water quality using macroinvertebrates to find the Saprobic score and Diversity score to indicate the level of pollution as well as to assess the biological quality of water. It entails the use of indicator species, generally, benthic macroinvertebrates/ fish and algae communities as well as certain aquatic plant species are also used. From several studies, benthic macro-invertebrate populations have been regarded as the most acceptable biological parameter to assess the quality of water out of all the biotic components. The mapping based on bio-monitoring has been proven as a powerful tool for the preparation of future action plans to control water pollution and improve the water quality of water bodies. The present study has been conducted in four major water bodies of city, Kolkata (West Bengal) using benthos monitoring to understand the prevailing scenarios.
The benthos samples were collected from all the four water bodies selected for study, sieved, washed, and transferred into a large tray for identification purposes and classified according to their taxa. As per the score obtained, most of the sampling sites were found to be moderately polluted. Gastropods, annelids, crustacea, and insects made up the majority of the benthic macro-invertebrate species that were collected. The various opportunities and lessons learned from past experiences of monitoring of different water bodies have also been included in this study. The details and significance of the work have been discussed in the full paper.