Relationship between structure characteristics of phytoplankton communities and environmental factors in the Niulan River Basin(Kunming part)
In order to explore the characteristics of phytoplankton community structure and its relationship with environmental factors in Niulan River Basin(Kunming part),phytoplankton species,cell density and water quality were investigated in 2022 during dry season,wet season and normal season.The characteristics of phytoplankton community structure and its relationship with environmental factors were analyzed in main stream and tributaries in the basin.The results showed that 240 species of phytoplankton were identified in 8 phyla,including 107 species(44.58％)of Chlorophyta,60 species(25.00％)of Bacillariophyta and 38 species(15.83％)of Cyanophyta.The cell density and dominant species were dominated by Cyanophyta and Bacillariophyta,followed by Chlorophyta.According to the time difference of phytoplankton community composition,the number of species of Bacillariophyta was the largest in dry season,followed by Chlorophyta.The number of species of Chlorophyta in wet and normal seasons was the largest,followed by Bacillariophyta.The Shannon-Wiener diversity index and Pielou evenness index showed that the water body of the basin was clean and low-pollution on the whole,while the Margalef richness index showed that the water body of the basin was in a mildly to moderately polluted state.Redundancy analysis showed that the main factors affecting the phytoplankton community distribution in the dry season were water temperature(WT),total nitrogen(TN)and current velocity(CV)in the wet season,and permanganate index,total nitrogen(TN)in normal season;the secondary factors were total phosphorus(TP),nitrate nitrogen,pH,transparency(SD)and ammonia nitrogen.
万方数据
