Comparison of physico-chemical parameters and phytoplankton species diversity of two perennial ponds in Sattur area, Tamil Nadu.

ABSTRACT

Investigations were carried out on the diversity of phytoplankton in relation to physico-chemical parameters with respect to pollution status of two perennial ponds of Sattur area, Tamil Nadu. Fifty species were identified belonging to Chlorophyceae, Bacillariophyceae, Cyanophyceae and Euglenophyceae. High value of physico-chemical parameters and low phytoplankton diversity were recorded in the Chinnapperkovil pond, whereas low value of physico-chemical parameters and high phytoplankton diversity were recorded in the Nallanchettipatti pond. Class Chlorophyceae qualitatively and quantitatively dominated in both the habitats when compared to other taxa. Present study revealed that phytoplankton species richness (R1 and R2) was comparatively higher (R1 5.43±0.53; R2 3.00±0.27) in Nallancheettipatti pond. The species diversity was high (H’ 3.08±0.37; N1 14.05±0.63; N2 12.55±0.94) in Nallanchettipatti pond compared to Chinnapperkovil pond (H’ 2.25±0.15; N1 12.59±0.80; N2 8.54±0.61). Anabaena aequalis, Nitzschia bilobata, Navicula membranacea, Scenedesmus annatus, Pediastrum leonensis, Frustulia rhomboides, Microcystis aeruginosa, Oscillatoria angusta, Closterium acerosum species dominated in Chinnapperkovil pond and Spirogyra maxima, Zygnema caeruteum and Fragilaria oceanica dominated in Nallanchettipatti pond. Abundance of such specific taxa (e.g. Closterium acerosum, C. dianae, C. lineatum, Anabaena aequalis, Oscillatoria angusta and Navicula membranacea) in the Chinnapperkovil and Nallanchettipatti (e.g. Merismopedia glauca and Fragilaria oceanica) ponds suggests that these taxa can be considered as pollution indicators. Phytoplankton species diversity and physico-chemical parameter profiles indicate the Chinnapperkovil pond to be meso-eutrophic whereas the Nallanchettipatti pond is oligo-eutrophic.