海州湾及其邻近海域浮游植物群落结构及其与环境因子的关系

Community structure of phytoplankton in Haizhou Bay and adjacent waters and its relationships with environmental factors

根据2011年春季（5月）、夏季（7月）、秋季（9月）和冬季（12月）在海州湾及其邻近海域开展的大面积综合调查数据,对海州湾浮游植物群落的种类组成、优势种、丰度以及多样性的时空变化特征进行研究,并应用典范对应分析（CCA）研究了环境因子对海州湾浮游植物群落结构的影响.本次调查共鉴定出浮游植物113种,隶属于3门44属.其中,硅藻门种类最多,共39属99种,占总种数的87.6%;甲藻门次之,共4属13种,占总种数的11.5%;金藻门仅1属1种.优势种中硅藻门主要以圆筛藻属和角毛藻属为主,甲藻门以角藻属为主,主要优势种为膜状缪氏藻、细弱圆筛藻、浮动弯角藻和派格棍形藻等,优势种组成具有明显的季节演替现象.海州湾各站位浮游植物的丰度为0.08×105~108.48×105cells·m-3,年平均丰度为10.71×105cells·m-3,其中,秋季最高（29.08×105cells·m-3）,夏季最低（1.69×105cells·m-3）.Shannon多样性指数（H）、均匀度指数（J）和丰富度指数（D）均为夏、秋季高,冬、春季低.典范对应分析（CCA）表明,影响海州湾及其邻近海域浮游植物丰度和分布的主要环境因子依次为海水表面温度（SST）、营养盐（NO3--N、PO43--P、SiO32--Si）和溶解氧（DO）,尤其是一些浮游植物优势种的丰度和分布与上述环境因子密切相关.

Based on the data collected from four seasonal surveys in 2011 in Haizhou Bay and adja- cent waters, community structure of phytoplankton was studied and their relationships with environ- mental factors were evaluated by canonical correlation analysis （CCA）. A total of 113 phytoplank- ton species belonging to 3 phyla and 44 genera were collected, among which Bacillariophyta species were the most abundant species, which included 39 genera and 99 species, accounting for 87.6% of total taxa, followed by Pyrrophyta, which included 4 genera and 13 species, accounting for 11.5 percent of total taxa. And the least abundant species were Chrysophyta species, which had only 1 species belonging to 1 genus. Among these dominant species, Coscinodiscus and Chaetoceros were the dominant groups in Bacillariophyta, while Ceratium was the dominant group in Dinophyta, and the dominant species were Meuniera membranacea, Coscinodiscus subtilis var. subtilis, Eucampia zo- diacus and Bacillaria paxillifera. There were obvious seasonal variations in the species composition and predominant species. The abundances of phytoplankton in all the stations ranged from 0.08×105 cells m-3 to 108.48×105 cells m-3 in Haizhou Bay. The average annual density of phytoplankton was 10.71×105 ceils m-3, being the highest in autumn （29.08~105 cells ~ m-3） and the lowest in summer （1.69×105 cells m-3）. The Shannon index, Pielou index and Margalef index of the phytoplankton community were higher in summer and autumn than in winter and spring. CCA suggested that the main factors affecting the phytoplankton community were sea surface temperature （SST）, followed by nutrients 〈 NO3--N, PO43-P, SiO32- -Si ） and dissolved oxygen （DO）. The abundances and distribution of some dominant species were closely related with these main factors.