为研究黄河流域藻类功能群分布及关键环境驱动因子,于2021年6-7月在黄河河南段设置16个采样位点,对黄河流域河南段浮游藻类群落组成、藻类功能群分布特征、不同空间环境因子特征及藻类-环境因子相关性进行分析,(1)共鉴定浮游藻类7门65属154种,在物种数上,绿藻门类(68种)>硅藻门类(60种)>蓝藻门类(11 种),以小环藻(Cyclotella sp.)、颗粒沟链藻极窄变种(Aulacoseira granulata var.angustissima)、束丝藻(Aphanizomenon sp.)、假鱼腥藻(Pseudanabaena sp.)为流域内主要优势种(优势度≥0.02);(2)黄河流域河南段浮游藻类共划分为23个功能群,分别是功能群B、C、D、E、F、G、H1、J、LM、Lo、M、MP、N、P、S1、T、W1、W2、X1、X2、X3、Xph和Y,所调查流域功能群空间分布差异较大,其中干流功能群种类最少,支流种类最多;从优势度来看,以适应富营养化、混动水体的功能群C、D、MP、P和J占优势;(3)RDA分析结果表明,优势功能群C与TN呈负相关;功能群MP与TP、NH+-N、WT、pH和CODMn呈负相关;功能群P与NH4+-N、WT和CODMn呈正相关;功能群D与TN呈正相关,功能群J与NTU呈正相关,与DO呈强负相关,其中CODMn是驱动藻类功能群分布的关键因子;(4)结合地表水环境评价、基于功能群的Q指数与Qr指数评价、生物多样性指数评价,此次调查流域水体呈重度氮污染,水库呈轻度磷污染,洛河流域相对其他支流水质偏差.
In order to investigate the phytoplankton functional groups distribution and its driving key factors,sixteen sampling sites were selected of the Yellow River Basin in Henan Province,involving two main streams,eleven tribu-taries and three reservoirs,from June to July,2021.According to the analysis of phytoplankton composition,distribu-tion of phytoplankton functional groups and the relationship between phytoplankton and environmental variables,results showed that(1)a total of 154 species belonging to 65 genera and 7 phyla were identified,mainly including Bacillariophyta,Cyanophyta,Chlorophyta,Dinoflagellata,Euglenophyta,etc.In terms of species abundance,Chloro-phyta(68 species)>diatom(60 species)>Cyanophyta(11 species);Cyclotella sp.,Auracoseira Granata var.angutis-sima,Aphanizomenon sp.and Pseudoanabaena sp.are the main dominant species in the basin(dominance ≥0.02),among which diatom is absolutely dominant and Chlorophyta is sub-absolutely dominant.(2)Phytoplankton in the Yellow River Basin in Henan Province are classified into 23 functional groups,namely assemblage B,C,D,E,F,G,H1,J,LM,Lo,M,MP,N,P,S1,T,W1,W2,X1,X2,X3,Xph and Y;the spatial distribution of functional groups in the investigated basin is quite different.The functional groups in main stream are the least and tributaries are the most,the functional groups C,D,MP,P and J that adapt to eutrophic and mixed water bodies are dominant.(3)RDA analysis showed that the dominant functional group C was negatively correlated with TN.MP was negatively correlated with TP,NH4-N,WT,pH and CODMn.Functional group P was positively correlated with NH4-N,WT and CODMn.Func-tional group D was positively correlated with TN,functional group J was positively correlated with NTU,and strongly negatively correlated with DO.Among them,CODMn was the key factor driving the distribution of algal functional groups.(4)Combined with surface water environment assessment,Q and Shannon-Wiener index,the Yellow river within Henan Province is suffering heavy-nitrogen pollution,whereas the reservoir is also slightly polluted by phospho-rus.In addition,it was suggested the Luohe River basin is more polluted than other tributaries.