Deciphering environmental factors influencing phytoplankton community structure in a polluted urban river  

作　　者：Xiaxia Li Kai Chen Chao Wang Tianyu Zhuo Hongtao Li Yong Wu Xiaohui Lei Ming Li Bin Chen Beibei Chai 

机构地区：[1]School of Water Conservancy and Hydroelectric Power,Hebei University of Engineering,Handan 056038,China [2]Collaborative Innovation Center for Intelligent Regulation and Comprehensive Management of Water Resources,School of Water Conservancy and Hydroelectric,Hebei University of Engineering,Handan 056038,China [3]Hebei Key Laboratory of Intelligent Water Conservancy,Hebei University of Engineering,Handan 056038,China [4]Tianjin Water Group Binhai Water Co.,Ltd.,Tianjin 300308,China [5]State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin,China Institute of Water Resources and Hydropower Research,Beijing 100038,China [6]School of Architecture and Civil Engineering,Xi’an University of Science and Technology,Xi’an 710054,China [7]Chengdu University of Technology,Chengdu 610059,China [8]College of Natural Resources and Environment,Northwest A&F University,Yangling 712100,China [9]State Key Joint Laboratory of Environment Simulation and Pollution Control,School of Environment,Beijing Normal University,Beijing 100875,China

出　　处：《Journal of Environmental Sciences》2025年第2期375-386,共12页环境科学学报(英文版)

基　　金：supported by the National Natural Science Foundation of China (No.72091511);the Science Fund for Distinguished Young Scholars of Hebei Province (No.E2022402064).

摘　　要：Tuojiang River Basin is a first-class tributary of the upper reaches of the Yangtze River—which is the longest river in China.As phytoplankton are sensitive indicators of trophic changes inwater bodies,characterizing phytoplankton communities and their growth influencing factors in polluted urban rivers can provide new ideas for pollution control.Here,we used direct microscopic count and environmental DNA(eDNA)metabarcoding methods to investigate phytoplankton community structure in Tuojiang River Basin(Chengdu,Sichuan Province,China).The association between phytoplankton community structure and water environmental factors was evaluated by Mantel analysis.Additional environmental monitoring data were used to pinpoint major factors that influenced phytoplankton growth based on structural equation modeling.At the phylum level,the dominant phytoplankton taxa identified by the conventional microscopic method mainly belonged to Bacillariophyta,Chlorophyta,and Cyanophyta,in contrast with Chlorophyta,Dinophyceae,and Bacillariophyta identified by eDNA metabarcoding.Inα-diversity analysis,eDNA metabarcoding detected greater species diversity and achieved higher precision than the microscopic method.Phytoplankton growth was largely limited by phosphorus based on the nitrogen-to-phosphorus ratios>16:1 in all water samples.Redundancy analysis and structural equation modeling also confirmed that the nitrogen-to-phosphorus ratio was the principal factor influencing phytoplankton growth.The results could be useful for implementing comprehensive management of the river basin environment.It is recommended to control the discharge of point-and surface-source pollutants and the concentration of dissolved oxygen in areas with excessive nutrients(e.g.,Jianyang-Ziyang).Algae monitoring techniques and removal strategies should be improved in 201 Hospital,Hongrihe Bridge and Colmar Town areas.

关 键 词：Environmental DNA Microscopic count Phytoplankton growth Structural equation modeling Tuojiang River Basin 

分 类 号：X171.1[环境科学与工程—环境科学]