2000年秋季渤海的网采浮游植物群落

Net-phytoplankton community of the Bohai Sea in the autumn of 2000

研究了2000年秋季覆盖渤海60个测站的网采浮游植物物种及其群落特征,共发现浮游植物3门35属64种(不包括未定名物种).物种主要以硅藻为主,但甲藻在群落中的比重也很明显,在个别站位上会成为优势类群.优势种主要为偏心圆筛藻、三角角藻、浮动弯角藻等,其中的偏心圆筛藻、浮动弯角藻、布氏双尾藻、梭状角藻和叉状角藻是秋季渤海浮游植物的关键种.细胞丰度的平面分布由浮游硅藻的分布决定,其高值区分布在渤海中北部、渤海湾南部和渤海海峡南部.浮游甲藻在渤海湾北部存在高值区.由于渤海环流的影响在渤海中北部存在浮游植物群落的交错区,此区物种丰富度高、多样性水平高和细胞丰度高.秋季渤海浮游植物群落物种丰富度、Shannon Wiener多样性指数和均匀度的高值区在渤海中部,但整个秋季浮游植物群落的多样性程度是较低的.

Features of phytoplankton community were studied based on the data of phytoplankton net samples from 60 grid stations investigated from 29th August to 4th September 2000 in the Bohai Sea, China. Three phyla including 35 genera and 64 species (not including unidentified taxa) were found in the survey area. The main phytoplankton group is diatom, but the dinoflagellates are also important in the phytoplankton community, it can be the dominant group at some stations. The dominant species are Coscinodiscus excentricus, Ceratium tripos and Eucampia zodiacus, etc. The key species phytoplankton in this season are Coscinodiscus excentricus, Eucampia zodiacus, Ditylum brightwellii,Ceratium fusus and Ceratium furca. The horizontal patterns of phytoplankton cell abundance are controlled by that of diatoms, it is high in the northern central Bohai Sea,the southern Bohai Gulf and the southern Bohai Straits. The dinoflagellates abundance is high in the northern Bohai Gulf. There is a phytoplankton ecotone formed by the Bohai Circulation Current in the northern central Bohai Sea, high species richness, high biological diversity and high cell abundance are found here. The species richness, the Shannon-Wiener index and the evenness of phytoplankton are relatively high in the central Bohai Sea. The fuzzy evaluation of biodiversity shows that phytoplankton community biodiversity in the Bohai Sea is low.