Freshwater Phytoplankton Diversity in an Indian Dam: A Study from Doswada, Tapi District, Gujarat

The phytoplankton diversity of Doswada Dam was studied to assess ecological health and eutrophication status. Eleventaxa were found, among which four of the dominating phyla consisted of Ochrophyta (2 taxa), Chlorophyta (4 taxa),Cyanobacteria (3 taxa), and Euglenophyta (2 taxa). Predominance of Chlorophyta and presence of bloom-forming cyanobacteriasuch as Microcystis aeruginosa, Oscillatoria sp., and Spirulina sp. indicated a nutrient-rich (eutrophic) habitat. Altogether, thecommunity structure of the phytoplankton indicated a moderately diverse and productive aquatic habitat with an initial indicationof nutrient loading. These results emphasised the necessity of biological monitoring for maintaining water quality in the reservoir.