Phytoplankton communities of eutrophic freshwater bodies (Kerala, India) in relation to the physicochemical water quality parameters

Abstract

Algal bloom of eutrophic freshwaters is important from different aspects of sustainable developmental perspectives. Apart from the identification of the algal species which multiply fast in response to eutrophication, phytoplankton studies concerning water quality parameters of eutrophic waters help environment inventory of such fast-growing algal species. The knowledge of specific environment requirements of fast-growing algae is highly significant in the control of toxic algal blooming and industrial utilization of non-toxic species in phycoremediation or as new bioresources for fuel, food or feeds. In this context, seasonal dynamics of the phytoplankton community in seven different kinds of eutrophic waters from 66 representative locations of Kerala, South India, was measured in two seasons. Altogether, 297 algal species belonging to 8 phyla, 11 classes and 26 orders were observed in the waters. Ecology and diversity of algal communities concerning physicochemical water quality parameters were compared, which enabled assessment of the ecological amplitude of several specific dominant species common to eutrophic waters in Kerala. The crucial roles of dissolved oxygen (p < 0.05), total Kjeldahl nitrogen (p < 0.01), and ammoniacal nitrogen (p < 0.05) in causing algal blooms are assessed using correlation analysis. The principal component analysis extracted the entire water quality parameters into five groups of components acting towards the cause of algal blooms. Overall, the investigation has generated relevant new information of several hitherto uninvestigated fast-growing non-toxic algal species such as Kirchneriella lunaris, Ankistrodesmus falcatus, Radiococcus nimbatus, Coelastrum microporum and Scenedesmus dimorphus, which are industrially useful and can contribute to ecotechnological innovations essential for sustainable development.