Diverse drivers of phytoplankton dynamics in different phyla across the annual cycle in a freshwater lake

An understanding of the annual variations in phytoplankton community freshwater lakes, and drivers responsible for these variations, is essential lake management. In this study we collected analyzed seasonal samples assessed environmental variables Nansi Lake from 2011 to 2015, order identify dynamics main each phylum. The results showed that diversity followed cycles, which were interrupted by a water diversion 2013. disruption equilibrium was clearly demonstrated Shannon–Wiener index, Pielou’s evenness Simpson’s dominance whereas species richness abundance resilience, maintaining regular cycles. dominant frequently Synedra acus Kütz (Bacillariophyta), Closterium gracile Bréb (Chlorophyta), Scenedesmus quadricauda (Chlorophyta) summer autumn. Non-metric multidimensional scaling (NMDS) analysis suggested most widely distributed summer, when conditions more conducive growth reproduction. Redundancy (RDA) indicated varied different taxonomic units. Specifically, NP ratio permanganate index (CODMn) had significant effects on Chlorophyta, pH, dissolved oxygen (DO), transparency significantly influenced Bacillariophyta. This highlights importance succession need identification phylum achieve effective control blooms lakes.