DRIVING FACTORS OF PHYTOPLANKTON COMMUNITY AND ASSESSMENT OF THE WATER QUALITY IN A SMALL EUTROPHIC WUXING LAKE, NORTHEAST CHINA

Abstract

The community structure, spatiotemporal variation and influencing factors of phytoplankton accompanied with water quality in Wuxing Lake, northeast China were studied during spring, summer and autumn from summer 2019 to spring 2020. Our purpose was to reveal the driving factors influencing phytoplankton community, combined with water quality, discussing methods on improving water quality in the lake.112 species of phytoplankton including 8 phyla and 74 genera were identified. The phytoplankton community structure demonstrated obvious seasonal and spatial variation. 20 dominant species were selected during three seasons. Redundancy analysis (RDA) result showed that transparency (SD), total phosphorous (TP), chemical oxygen demand (CODCr), turbidity (Tur), dissolved oxygen (DO) and conductivity (EC) were main factors influencing the abundance of dominant species. Results of Shannon-Wiener index (H’) and Pielou’s evenness index (J’) indicating slight to light pollution in the lake. Considering the risk of deterioration of water quality is still a possibility, measures to improve SD may be effective to prevent Cyanophyta blooms in summer. Our findings will provide a reference for water quality protection and management in small eutrophic lakes similar to Wuxing Lake.