浙南大罗山天河水库浮游植物群落结构的季节变化及对水质的指示作用

为了探究浙南地区山区水库浮游植物群落结构的季节变化及水质状况,于2019年2月—2020年1月对位于温州大罗山天河水库的浮游植物群落结构和水体理化因子进行了调查分析。结果表明: 天河水库浮游植物隶属于7门60属89种,全年浮游植物平均丰度为2.02×10⁵ cells·L^-1,年均生物量为0.26 mg·L^-1。硅藻门在全年均占优势,绿藻门在春、秋季占优势,而蓝藻门仅在夏季占优势,裸藻门和甲藻门在全年均有出现,隐藻门在秋、冬季均有出现,但不占优势。全年主要优势种有颗粒直链藻、尖针杆藻、隐头舟形藻、美丽星杆藻、假鱼腥藻、小新月藻、二角盘星藻、二角多甲藻、圆筒锥囊藻、卵形隐藻。冗余分析(RDA)显示,水库的水温、总氮、化学需氧量(COD_Mn)和 pH值是浮游植物群落结构的主要影响因子。分别运用Shannon指数、Pielou均匀度指数和Margalef丰富度指数,并结合浮游植物的丰度、优势种及综合营养状态指数分析了水体污染情况和富营养程度, 结果显示,天河水库水体介于寡污染到清洁水体带之间,为贫-中营养型水体。

Seasonal variation of phytoplankton community structure in the Tianhe Reservoir of the Daluoshan Mountain in southern Zhejiang Province,China and its indication to water quality

To explore the association between phytoplankton community structure and water quality of the Tianhe Reservoir in Wenzhou, Zhejiang, we examined the phytoplankton and physico-chemical factors in the Tianhe Reservoir from February 2019 to January 2020. A total of 89 phytoplankton species belonging to 60 genera and 7 phyla were identified. The annual average abundance and biomass of phytoplankton were 2.02×10⁵ cells·L^-1 and 0.26 mg·L^-1 respectively. Bacillariophyta was dominant in the whole year. Chlorophyta was dominant in spring and autumn. Cyanophyta was dominant in summer. Both Euglenophyta and Pyrrophyta appeared in the whole year. Cryptophyta appeared in autumn and winter. However, none of them was dominant due to their low abundance. The dominant species throughout the year were Melosira granulata, Synedra acus, Navicula cryptocephala, Asterionella formosa, Pseudoanabaena, Closterlum venus, Pediastrum duplex, Peridinium bipes, Dinobryon cylindricum and Cryptomonas ovata. Results of redundancy analysis (RDA) showed that water temperature, total nitrogen, COD_Mn and pH value were the main factors driving phytoplankton community structure in the whole year. According to the evaluation based on diversity indices, including Shannon index, Pielou evenness index, Margalef richness index and comprehensive trophic status index (TLI), water quality of Tianhe Reservoir is between oligotrophication and mesotrophication.