[Relationship Between the Phytoplankton Distribution and Environmental Factors in Fenhe Scenic Spot of Taiyuan].

In order to explore the structural characteristics of phytoplankton community and the water quality and the water quality of the Fenhe scenic spot in Taiyuan, the species composition and the biomass of phytoplankton as well as their correlation with the environmental factors were monitored. The survey selected 9 sampling sites along the up and lower reaches in Fenhe scenic spot of Taiyuan, from Chaicun Bridge to Xiangyun Bridge. During the wet season (June-Octoher) in 2014, specimens were collected, qualitative and quantitative investigation on the algae and monitoring on physicochemical indexes of the water were studied. Meanwhile, the water quality was analyzed and evaluated combining all the physicochemical indexes and cell density. Correlation analysis and RDA were conducted to analyze the relationship of algal community structure and the environmental factors. The main results showed that the dominant phytoplanktons were Cyanophyta, Chlorophyta and Bacillariophyta. The algal biomass first increased and then reduced during the wet season, and the maximum value of hiomass occurred in July. There were many differences among different sampling points. The cell densities of phytoplankton were much higher in three central areas than the other sampling sites. Physical and chemical factors showed a variation tendency in time and space. Based on the results of RDA hetween phytoplankton cell densities and the physic-chemical parameters, the cell densities and the physic..chemical parameters had different correlations. The total cell density had significant positive correlation with dissolved oxygen, and negative correlation with COD. There were extremely significant positive correlations between diatom cell densities and water temperature, air temperature. But the diatom cell density was obviously negatively correlated with COD. It was distinct that the functions of the environment factors were different in temporal and spatial distrihution. The state index of comprehensive nutrition indicated that the total nitrogen content was beyond the standard in all sampling sites during the whole wet season. The water quality varied from oligotrophic to light eutrophic.