Plankton biodiversity of Dharamtar creek adjoining Mumbai harbour

Abstract

The phytoplankton and zooplankton diversity of Dharamtar creek, a vital system adjoining the Mumbai harbour were assessed to obtain baseline information. A total of 58 genera of phytoplankton were encountered from the area, which included 46 diatoms, 6 dinoflagellates and 6 other algae. Variation in phytoplankton cell count was enormous (17-5980 x 10 sup(3) l sup(-1)) with an average cell count of 266 x 10 sup(3) l sup(-1). The phytoplankton community was dominated by diatoms (97.6%) followed by dinoflagellates (2%) and other algae (0.4%). Blooms of Skeletonema and Peridinium were respectively observed during October - November and December. Shannon and Weaver's diversity index HI ranged from 0.29 - 3.6 (av. 2.42) while Margalet's D varied from 1.4-4.93 (av. 2.96). Zooplankton population density varied between 3091 & 1723786/100m sup(3) (av.126986/100m sup(3)). Copepods formed the largest group of zooplankton population (71.9%) comprising 46 species belonging to 23 genera. Dharamtar creek sustains a rich plankton community. However, recent industrial development along the banks of creek may pose the problem due to waste disposal into this creek system. Losses of marine life diversity are largely the results of conflicting uses, in particular coastal habitat, which leads to degradation of habitats. The best way to conserve biodiversity is to protect habitat diversity.