Assessment of algal diversity and carbon sequestration potential of Arthrospira platensis and Scenedesmus vacuolatus isolated from the urban gravel pit lake in Chennai, South India—a biomass production approach from the novel areas

Abstract

Global warming and increasing CO₂ play an important role in making terrestrial and aquatic life highly pathetic. Microalgae have many advantages over other methods in bioremediation and carbon sequestration including eco-friendly nature, less space requirement, and sustainable energy production from wastes. The aim of the present investigation is to assess the microalgal diversity, followed by isolation of microalgae from the abandoned urban man-made ecosystem and evaluation of their carbon fixation potential. Samples were collected for a year (October 2021–September 2022). The prominent water quality parameters were estimated. The Statistical Package for Social Sciences, version 26.0, was used to estimate Karl Pearson’s correlation coefficient and one-way analysis of variance. Paleontological Statistics (version 4.03) was used to estimate the diversity indices. Sixty species categorized into 7 classes, 19 orders, and 41 genera were identified. The quantitative spectrum revealed that Bacillariophyceae was the dominant class (231 cells/L) followed by Chlorophyceae (220 cells/L). In carbon sequestration, Scenedesmus vacuolatus (6.50 mg/L/h) performed more efficiently than Arthrospira platensis (1.81 mg/L/h). It is vital to explore the occurrence of microalgae from all possible wet environments, which further can be isolated and employed in various biotechnological applications.