金河湾城市湿地浮游植物功能类群演替及驱动因子

于2015年春(5月)、夏(8月)、秋(10月)三季,在金河湾湿地4类水体共设置12个采样点对浮游植物功能类群演替及与水环境变量关系进行分析。研究期间共鉴定浮游植物376个种,隶属于8门10纲19目19科101属。浮游植物种类组成主要以硅藻门(39.62%)和绿藻门(35.64%)为主,其次裸藻门(10.11%)和蓝藻门(9.84%)的藻类所占比例较高,甲藻门、隐藻门、金藻门和黄藻门所占比例较低。调查期间金河湾湿地浮游植物细胞丰度季节间差异显著(P0.05),整体上呈现夏季秋季春季的规律。春、夏、秋三季共划分20个不同的功能类群,双因素方差分析(Two-way ANOVA)和单因子交叉相似性检验(One-way ANOSIM)表明:代表性功能类群在季节间演替明显(P0.05),群落构成差异显著(P0.01)。SIMPER分析指出,S2/H1/B/D/Lo/X1/MP是引起金河湾湿地各季节之间浮游植物群落结构差异的主要贡献类群。通过代表性功能类群和10个水环境变量的典范对应分析(CCA)探索环境变量与功能类群演替的关系。经分析,总氮(TN)是驱动金河湾湿地浮游植物功能类群演替的主要环境变量,电导率(SpCond)、pH与功能类群演替密切相关。

Study on phytoplankton functional group succession and driving parameters in the Jinhewan Urban Wetland

The Jinhewan Wetland is located in northeastern China, and plays an important role in protecting the biodiversity and regulating the microclimate in Harbin City. Although phytoplankton community studies on wetlands from northern China have increased recently, studies of the phytoplankton community in the Jinhewan Wetland are limited. To better understand processes of phytoplankton community succession in relation to environmental parameters, a detailed survey of phytoplankton functional groups in spring, summer, and autumn are necessary. Therefore, we studied the phytoplankton functional groups and 10 environmental parameters during spring (May), summer (August), and autumn (July). The aim of this study was to understand the succession process of phytoplankton functional groups between seasons, and furthermore explore the dynamic parameters in the Jinhewan Wetland. In this study, phytoplankton were qualitatively and quantitatively collected from 12 sampling sites in four typical habitats. A total of 376 phytoplankton species were identified, belonging to 8 families, 10 classes, 19 orders, 19 families, and 101 genera. The phytoplankton species composition was dominated by Bacillariophyta (39.62%) and Chlorophyta (35.64%), followed by Euglenophyta (10.11%) and Cyanobacteria (9.84%), and the proportions of Pyrrophyta, Cryptophyta, Chrysophyta, and Xanthophyceae were relatively low. Our study showed that the average abundance of phytoplankton in the Jinhewan Wetland was significantly different (P < 0.05). The average abundance in summer was the highest (12.90×10⁶ ind/L), followed by autumn (5.95×10⁶ ind/L), and spring (2.55×10⁶ ind/L). The range of change was 0.97-14.83×106 ind/L, ranging between 0.47-30.17×10⁶, 5.95×10⁶, and 2.55×10⁶ ind/L, respectively. We arranged phytoplankton taxa data from spring, summer, and autumn into 20 functional groups. Groups B/D/F/H1/J/MP/S2/X1 were predominant in spring, groups B/D/H1/Lo/S1/S2/SN/MP/Y were predominant in summer, and groups B/D/F/H1/J/MP/S2/X1 were predominant in autumn. A two-way ANOVA and single-factor cross-similarity test (one-way ANOSIM) showed that there were significant differences in representative functional groups between spring, summer, and autumn (P < 0.05), the representative functional group succession was obvious (P < 0.05), and functional group assemblages were significantly different (P < 0.01). In addition, a SIMPER analysis indicated that the primary contributing phytoplankton functional groups were S2/H1/B/D/Lo/X1/MP in the Jinhewan Wetland. A Canonical Correspondence Analysis (CCA) based on representative functional groups of 10 environmental variables revealed that total nitrogen (TN) was the primary factor affecting the phytoplankton functional group succession in this wetland, and conductivity (SpCond) and pH were closely related to phytoplankton functional group distribution.