海河流域天津段浮游植物功能群分布特征及其与环境因子的关系

Distribution Characteristics of Phytoplankton Functional Groups and Their Relationship with Environmental Factors in Tianjin Section of Haihe River Basin

为分析海河流域不同水文期浮游植物功能群分布特征及影响因子,于2023年4月(枯水期)和2023年9月(丰水期)在海河流域天津段设置15个采样点,对浮游植物群落结构及水体理化指标进行了调查。通过对海河流域天津段的浮游植物进行分析,研究其物种组成、功能群分布特征,并探究不同水文期环境因素与浮游植物功能群之间的相关性。结果表明:①海河流域天津段共检出浮游植物7门140种,在物种数上呈硅藻门>蓝藻门>裸藻门的特征,尖针杆藻(Synedraacus)、束丝藻(Aphanizomenonsp.)、裸甲藻(Gymnodinium sp.)、卵形隐藻(Cryptomonas ovata)、颗粒直链藻(Melosira granulate)和裸藻(Euglena sp.)为研究区域内主要优势种(优势度≥0.02)。②浮游植物归属于23个功能群,其中优势功能群有8种,分别为A、D、H1、L_(O)、MP、P、TB和Y。③RDA分析结果表明,丰水期水温(WT)和高锰酸盐指数(COD_(Mn))是显著影响海河流域天津段浮游植物功能群的关键因子,枯水期海河流域天津段浮游植物功能群的关键环境影响因子为高锰酸盐指数(COD_(Mn))。④应用Shannon-Wiener多样性指数和基于功能群的生态指数(Q_(r)指数)评价法对海河流域天津段进行水质评价,均显示调查区域水质处于清洁状态,两种评价方法得出的结果较为一致,均具有很好的指示作用。研究显示,功能群能直观反映海河流域天津段浮游植物特征,Qr指数能客观指示海河流域天津段水质状况。

In order to analyze the distribution characteristics and influencing factors of phytoplankton functional groups in the Haihe River Basin,surveys were conducted at 15 sampling sites in the Tianjin section of the Haihe River Basin in the dry season(April 2023)and the rainy season(September 2023).This study aimed to explore the species composition and functional group distribution characteristics of phytoplankton and the correlation between environmental factors and phytoplankton functional groups in different hydrological periods.A total of 140 of phytoplankton species from 7 phyla were identified,the species numbers were Bacillariophyta,Cyanophyta and Euglenophyta.The dominant species(dominance≥0.02)in the study area included Synedra acus,Aphanizomenon sp.,Gymnodinium sp.,Cryptomonas ovata,Melosira granulate and Euglena sp..In addition,23 functional groups were identified,among which A,D,H1,L_(O),MP,P,TB and Y were the major functional groups.The results of RDA analyses showed that water temperature(WT)and permanganate index(COD_(Mn))were important factors affecting phytoplankton functional groups during the wet season,while during the dry season,the key environmental influence was the permanganate index(COD_(Mn)).Furthermore,the water quality evaluation using the Shannon-Wiener diversity index and the Ecological index evaluation method based on functional group(Q_(r)index)indicated that the water quality in the investigated area was clean,providing consistent and positive results.The study showed that functional groups can directly reflect the phytoplankton characteristics in the Tianjin section of the Haihe River Basin,and Qr index can objectively reflect the water quality in the Tianjin section of the Haihe River Basin.