This study intends to grasp the distribution characteristics of phytoplankton in upstream reservoir and understand the ecolog-ical status of the reservoir area.Phytoplankton collection was conducted on August 13,2021(high-water season)and May 3,2022(low-water season)in upstream reservoir.The relationship between phytoplankton community structure and environmental factors in upstream reservoirs explore by redundancy analysis(RD A).The results showed that a total of 29 genera and 40 species of phytoplank-ton in 6 phyla were identified in 5 typical water sections of the upper reservoir.At the phyla level,Bacillariophyta was the dominant population in both water periods,accounting for 40.00％of the total classes.Chlorophyta and Cyanophyta account for 27.50％and 20.00％of the full courses.Euglenophyta,Phaeothamnion,and Cryptophyta were less abundant than the above species.At the species level,the dominant species were Cyclotella meneghiniana,Cymbella sp.and Nitzschia palea.The differences in phytoplankton commu-nity structure between the two water periods were significant(P＜0.05),and the number of species and biomass were higher in the low-water season than in the high-water period.The phytoplankton biomass and density analysis evaluated that the upstream reservoir was nutrient-poor.The planktonic Shannon-wiener index was 2.83,the Margalef index was 2.97,and the Pielou index was 0.56.The RDA results indicated that electrical conductivity(EC),water temperature(WT),and dissolved oxygen(DO)were the main envi-ronmental factors influencing the changes in phytoplankton communities in the upstream reservoir.This study aims to provide a scientif-ic basis for enriching the ecological diversity of the upstream reservoir waters and maintaining their sustainable development.
维普
万方数据