Phytoplankton biodiversity and the application in water quality assessment in Phai Loan lake, Lang Son city

Abstract

Phai Loan lake is located in the center of Lang Son city. Qualitative and quantitative samples of phytoplankton from Phai Loan lake were collected at six research points with 2 sampling periods in May and October 2024. Results of phytoplankton identification showed that 53 species and subspecies of phytoplankton were recorded, belonging to 17 families, 8 orders of 4 phyla. There are 27 species of Bacillariophyta, 13 species of Chlorophyta, 6 species of Euglenophyta, and Cyanobacteriophyta has 7 species. Phytoplankton density ranges from 5128 to 6260 cells/liter. Bacillariophyta had the largest density of species. Euglenophyta had the smallest algae density. The Palmer index, Euglenophyta index, and D index show that Phai Loan lake is moderately polluted.