[Driving Factors Analyze of Phytoplankton Community by Comparison of Population and Functional Groups and Water Quality Evaluation in Dongting Lake].

Phytoplankton is the most important component of water ecosystems, which could indicate the state of the water environment owing to its sensitivity to water environment variation. However, its response to the environment is influenced by classification methods. To understand the phytoplankton population(phyla and genera) and functional groups(FG) for driving response characteristics and applicability to the environment in Dongting Lake, a total of four samples were collected from the lake from March to December 2019, and the distribution characteristics of the phytoplankton population and functional groups and their responses to environmental factors were compared and analyzed.

[Vertical Stratification Characteristics of Dissolved Oxygen and Phytoplankton in Thousand-Island Lake and Their Influencing Factors].

According to the data collected from the five monitoring sites in front of the dam in Thousand-island Lake in September 2015, the vertical distribution characteristics of dissolved oxygen (DO), water temperature, pH, turbidity, conductivity and phytoplankton were analyzed. The influencing factors of special stratification of DO and vertical distribution of phytoplankton were also discussed. The results showed that:① The vertical distribution of DO presented "the surface is higher than the underlying" mode.