李亚军 王先明 程贤松 魏盟智 邓晓东

摘  要：美济礁位于我国南沙群岛中东部，其自然资源丰富，为探明近岸海域夏季浮游植物群落结构特征、水质因子及其两者之间的关系，于2018年8月对美济礁近岸海域12个站次的网采浮游植物进行调查，共记录浮游植物83属199种。硅藻门和甲藻门的种类组成占绝对优势，主要优势种有距端根管藻、红海颤藻、薄壁几内亚藻、翼根管藻纤细变型、透明辐杆藻、舟形藻、裸甲藻、双眉藻和伏氏海毛藻。美济礁浮游植物多样性程度较高，种类比较丰富，多样性指数、均匀度和丰富度平均分别为4.21、1.18和6.64。其中，礁盘外的浮游植物多样性程度要高于礁盘内。电导率和硝酸盐氮含量是影响浮游植物群落结构的显著影响因子。电导率越高，浮游植物多样性水平越高。硝酸盐氮含量越高，浮游植物群落的丰富度则越低。本次调查研究为南沙群岛生态系统以及热带珊瑚礁生态系统提供了基础资料。

关键词：美济礁;浮游植物;群落结构;环境因子

中图分类号：Q948.1      文献标识码：A

The Characteristics of Summer Phytoplankton Community in Meiji Reef， Nansha Islands， South China Sea

LI Yajun， WANG Xianming， CHENG Xiansong， WEI Mengzhi， DENG Xiaodong*

Institute of Tropical Bioscience and Biotechnology， Chinese Academy of Tropical Agricultural Sciences / Hainan Provincial Key Laboratory for Functional Components Research and Utilization of Marine Bioresources， Haikou， Hainan 571101， China

Abstract： Based on 12 samples collected from the sea waters near Meiji Reef in August 2018， the characteristics of the phytoplankton community and environment factors were analyzed. The results showed that a total number of 199 species belonging to 83 genera， in which diatoms and dinoflagellates were predominant in the species composition and the cell abundance. The dominant species were Rhizosolenia calcaravis， Oscillatoria erythraea， Guinardia flaccida， R.alata f. gracillima， Bacteriastram hyalinum， Navicula sp.， Gymnodinium aeruginosum， Amphora sp. and Thalassiothrix frauenfeldii. The Meiji Reef waters were rich in phytoplankton species， the average Shannon-Wiener diversity index， Pielou evenness index and Margalef diversity index was 4.21， 1.18， 6.64， respectively. In addition， there were more phytoplankton species outside the reef than those in the reef. Conductivity and nitrate content were the main environment factors affecting the phytoplankton community structure. The phytoplankton diversity had positive relationship with conductivity， and negative relationship with nitrate content.

Keywords： Meiji Reef; phytoplankton; community structure; environment factors

DOI： 10.3969/j.issn.1000-2561.2020.03.027

浮游植物是海洋食物鏈的初级生产者，对海洋生态系统中的能量流动和物质循环起着非常重要的作用。浮游植物的群落结构组成与海洋环境休戚相关，其可以灵敏而快速地反映海洋环境的变化，反之，海洋环境的变化也可改变浮游植物群落结构的种类组成和分布[1]。同时，地球上40%的光合作用来源于海洋浮游植物[2]。因此，研究浮游植物的群落结构对了解海洋生态系统，乃至全球生态系统都具有非常重要的意义。……