2008年夏季南海北部浮游植物群落结构特征分析

根据2008年8月15日—2008年9月7日南海北部调查期间所获得的网采浮游植物资料,对该海域的4个断面共计13个站位的浮游植物群落结构特征进行了研究,包括种类组成、丰度、分布、多样性以及浮游植物群落结构与环境因子之间相关关系等基本状况。本次调查共鉴定出浮游植物4门53属169种(含变种和变型),主要以暖水性、广温性和广布性种为主,其中硅藻门(Bacillariophyceae)37属114种,占总种数的67.4%,甲藻门(Pyrrophyta)12属50种,占总种数的29.6%,蓝藻门(Cyanophyta)2属3种及金藻门(Chrysophyta)2属2种等。浮游植物丰度平均值为18.06×104cells/m3,其中硅藻丰度平均值为55.72×106cells/m3,甲藻丰度平均值为0.81×106cells/m3。调查区域内的优势种包括铁氏束毛藻(Trichodesmium thiebautii),洛氏角毛藻(Chaetoceros lorenzianus),柔弱菱形藻(Nitzschia delicatissima),红海束毛藻(Trichodesmium erythraeum)和菱形海线藻(Thalassionema nitzschioides)。藻类为聚类分析(UPMGA)将站点大致上分为4个生态区(珠江口生态区,吕宋海峡区,琼东上升流区和18°N断面区),结果表明,在地理位置上分布比较相近的站点具有较高的群落结构组成相似性。

Structure characteristics of phytoplankton community in Northern South China Sea in the summer of 2008

The cruise survey over Northern South China Sea was conducted between August,15th and September 7th,2008.The investigation area consisted of 13 stations are belonging to four transects.The factors like species composition,abundance,spatial distribution,diversity of phytoplankton and the structure of the phytoplankton communities were studied.The results showed that 169 species of 53 genera belonging to 4 phyla were identified.The analysis showed that 67.4% of all identified species were Bacillariophyta(37 genera and 114 species) and 29.6% were Pyrrophyta(12 genera and 50 species).Phylum Cyanophyta and Chrysophyta were consisted of 2 species and 3 genera and 2 species and 2 genera,respectively.The average cell abundance of phytoplankton was 18.06×106 cells/m3 and the abundance of Phylum Bacllariophyta and Pyrrophyta were 55.72×106 cells/m3 and 2.28×106 cells/m3,respectively.The dominant species were Trichodesmium thiebautii,Chaetoceros lorenzianus,Nitzschia delicatissima,Trichodesmium erythraeum and Thalassionema nitzschioides.The analysis of the sampling sites by un-weighted pair group method with arithmetic averages(UPGMA) showed that sites could be divided into four subclasses(Pearl River Zone,Luzon Strait Zone,QiongDong Upwelling Zone and 18 N Transect).Result showed the similar phytoplankton community composition based on the geographical proximity.