桑沟湾浮游植物群落结构时空变化特征及影响因素

Temporal and spatial variation in phytoplankton community structure and their relationship with environmental factors in Sanggou Bay

中文关键词: 浮游植物  群落结构  营养盐  滤食性贝类  桑沟湾

英文关键词: Phytoplankton  Community structure  Inorganic nutrients  Filter-feeding bivalves  Sanggou Bay

中文摘要:

      为了解北方典型养殖海湾——桑沟湾水域浮游植物群落结构的时空变化特征及其影响因素，于2017年4月(春季)、7月(夏季)、11月(秋季)和2018年1月(冬季)对桑沟湾水域21个站点进行4个航次的大面调查。结果显示，调查期间，该湾共采集到浮游植物31属51种，其中，硅藻(Diatom) 24属43种，甲藻(Dinoflagellate) 3属4种，绿藻(Chlorophyta) 2属2种，金藻(Chrysophyta) 2种，蓝藻(Cyanophyta) 1种。按照季节划分，春季22种，夏季20种，秋季23种，冬季20种。优势度指数分析结果表明，硅藻是绝对优势种，其中，具槽帕拉藻(Paralia sulcate)为全年优势种，数量百分比在18.6%~84.9%之间。浮游植物细胞丰度在0.16×103~12.20×103个/L之间，表现为冬季>春季>秋季>夏季。物种多样性指数(Shannon)范围为0.69~1.35，物种均匀度指数J (Pielou)范围为0.42~0.70。磷酸盐是桑沟湾浮游植物生长的主要限制营养盐。研究结果揭示了桑沟湾养殖水域浮游植物的时空变化特征，为深入认识养殖生态系统的结构和功能提供了基础数据。

英文摘要:

      In order to better understand the temporal and spatial variation in characteristics of phytoplankton community structure and their relationship with environmental factors in Sanggou Bay, four seasonal cruises were carried out at 21 sites in April (spring), July (summer) and November (autumn) 2017 and in January 2018 (winter). Analysis identified 51 species from 31 phytoplankton genera in the surveyed area. Among these, 43 species were from 24 genera of diatoms, 4 species from 3 genera of dinoflagellates, 2 species from 2 genera of Chlorophyta, and 1 species of Cyanophyta. Seasonal analysis showed that there were 22 species in spring, 20 species in summer, 23 species in autumn, and 20 species in winter. The dominance index showed that diatoms comprised the dominant species, and that Paralia sulcata was the dominant species throughout the year, with percentages ranging between 18.6% and 84.9%. The abundance of phytoplankton cells ranged from 0.16×103 cells/L to 12.2×103 cells/L (winter > spring > autumn > summer). The species diversity index (Shannon-Wiener index) varied from 0.69 to 1.35 (autumn > summer > winter > spring). The species evenness index J (Pielou) ranged from 0.42 to 0.70. Phosphate is the main limiting nutrient for phytoplankton growth in Sanggou Bay. The results reveal the spatial and temporal variation characteristics of phytoplankton community in a typical large-scale mariculture bay and provide the basic data for in depth understanding of the structure and function of the mariculture ecosystem.