Variation in Benthic population in two basins of Bhoj Wetland, Bhopal

In order to assess the trophic status of a multipurpose aquatic resource (Bhoj wetland), the main attention was focused on its benthic population as it gives a fare idea about the functioning of the system besides assessing its trophic status, necessary from the point of view of adopting a management strategy. Upper basin of Bhoj wetland still forms the lifeline of Bhopal by way of providing potable water to the local habitants however, looking to its multiple uses it has been notified as per the guidelines of Ramsar convention as one of the important bird sanctuary.

Considerable variations in benthic fauna have been recorded in both the water bodies. During the present study benthic fauna were represented by seven different classes belonging to Mollusca, Diptera, Trichoptera, Oligochaeta, Crustacea, Hirudinea and Ephemeroptera. Upper basin is richer in terms of species richness in comparison to the Lower basin. The dominance of Molluscan population in both the basins in terms of diversity and density has been recorded.

Physico-chemical study revealed higher trophic status of Lower basin of Bhoj wetland in comparison to its Upper basin. Acidic pH values (6.43–6.9 units) of sediments of both the basins were also recorded. Also the values of Nitrate and Orthophosphate depicted their higher accumulation in the bottom waters of both the basins.