摘要
浮游植物对维持湖泊和水库生态系统结构和功能具有重要作用.为了解长江口崇明岛湖库水体不同水文时期浮游植物群落变化特征及其主要驱动因子,于2020年8月(丰水期)和12月(枯水期),以及2021年4月(平水期),对岛上的东风西沙水库、明珠湖、北湖浮游生物与水质理化因子展开调查.结果表明:共鉴定出浮游植物6门62属106种,主要优势种为蓝藻门的湖生假鱼腥藻(Pseudanabaena limnetica)、链状假鱼腥藻(Pseudanabaena catenate)、泽丝藻(Limnothrix sp.)、点形平裂藻(Merismopedia punciata)等非固氮类群和绿藻门的小球藻(Chlorella sp.).PCoA及Anosim相似性分析表明,不同时间段浮游植物群落结构具有极显著差异(p<0.01),高温季表现为蓝-绿藻型,而低温季则为硅-隐藻型.RDA分析表明,水温、氮营养盐和有机污染物是影响浮游植物群落结构变化的关键因子.丰水期浮游动物摄食作用(下行效应)对藻类群落结构影响较强,其他时期主要受非生物环境因子(上行效应)影响.在崇明岛湖库水体今后生态保护中,可着重关注氮和有机物变化,同时可考虑通过生态修复手段提高水体大型浮游动物丰度,以增强对藻类摄食,防止“水华”发生.
Phytoplankton plays an important role in maintaining the integrity and function of lake and reservoir ecosystems.To understand the variation of phytoplankton community and its main driving factors in different hydrological periods of Chongming Island in the Yangtze River Estuary,the plankton and physical and chemical parameters in Dongfengxisha Reservoir,Mingzhu Lake and Beihu Lake were investigated in August(wet season)and December(dry season)of 2020,and April(normal season)of 2021.The results showed that 106 phytoplankton species across 62 genera and 6 phyla were identified.The main predominant species were non-nitrogen-fixing groups such as Pseudanabaena limnetica,Pseudanabaena catenate,Limnothrix sp.,Merismopedia punciata,and Chlorella sp.Principal component analysis(PCoA)and Anosim similarity analysis showed that there were significant differences in phytoplankton community structure associated with different water regimes(p<0.01).The high-temperature season was characterized by Cyanophyta-Dinophyta dominance,while the low-temperature season was marked by Bacillariophyta-Cryptophyta dominance.Redundancy analysis(RDA)showed that water temperature,nitrogen nutrients,and organic pollutants were the key factors affecting phytoplankton community structure.The influence of zooplankton grazing(top-down effect)was more pronounced during the wet season,while abiotic environmental factors(bottom-up effect)were predominant in other periods.Therefore,in the future ecological protection of the lakes and reservoirs in Chongming Island,should be focused on the changes in nitrogen and organic matter.Meanwhile,the increasing abundance of macro-zooplankton in the aquatic ecosystem through ecological restoration methods need to consider to boost phytoplankton consumption and prevent the the risk of algal bloom.
作者
丁改变
苏敬华
周晗
徐后涛
王丽卿
张玮
DING Gaibian;SU Jinghua;ZHOU Han;XU Houtao;WANG Liqing;ZHANG Wei(Engineering Research Center of Environmental DNA and Ecological Water Health Assessment,Shanghai Ocean University,Shanghai 201306;Shanghai Academy of Environmental Sciences,Shanghai 200233;Shanghai Aqua-life Environment Engineering Co.,Ltd,Shanghai 200090;Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources,Ministry of Education,Shanghai Ocean University,Shanghai 201306)
出处
《环境科学学报》
CAS
CSCD
北大核心
2024年第9期390-400,共11页
Acta Scientiae Circumstantiae
基金
上海市生态环境局(No.沪环科[2023]第48J号)
上海市科委科研项目(No.23DZ1204300)。
关键词
崇明岛
湖库水体
浮游植物群落
不同水文时期
驱动因子
Chongming Island
lakes and reservoirs
phytoplankton community
different hydrological periods
driving factor
