2006年冬季北黄海网采浮游植物群落结构

Community structure of net-phytoplankton in the northern Huanghai Sea in the winter of 2006

根据2006年12月30日—至2007年1月17日北黄海的调查资料,对该海域浮游植物的种类组成、优势种、丰度及其分布和多样性等基本状况进行了分析。本次调查共鉴定浮游植物4门68属131种,主要以温带近岸和广布性种为主,其中硅藻有53属113种,占总种数的86.3%,甲藻有11属16种,占总种数的12.2%。浮游植物丰度平均值为88.89×104个/m3,硅藻丰度平均值为86.58×104个/m3,甲藻丰度平均值为2.28×104个/m3,硅藻丰度分布趋势决定了浮游植物丰度的分布趋势。辽宁南岸是浮游植物密集区,山东半岛北岸其次,而北黄海中部是浮游植物的稀疏区。优势种为:短角弯角藻(Eucampia zodiacus)、具槽帕拉藻(Paralia sulcata)、尖刺拟菱形藻(Pseu-do-nitzschia pungens)、密连角毛藻(Chaetoceros densus)、柔弱角毛藻(Chaetoceros debilis)、刚毛根管藻(Rhizosolenia setigera)。浮游植物群落Shannon-Weiner物种多样性指数平均值为1.80,Peilou均匀度指数平均值为0.42。与1959年1月相比,2007年1月北黄海浮游植物丰度由150.00×104个/m3降为88.89×104个/m3,下降了近41%,硅藻丰度由148.00×104个/m3降为86.58×104个/m3,而甲藻丰度由1.25×104个/m3上升为2.28×104个/m3,占浮游植物丰度的比例由0.8%上升为2.5%。主要优势种及优势属也发生了一定程度的变化,但浮游植物群落结构仍以硅藻为主、甲藻其次,浮游植物丰度总的分布格局变化不明显。

The species composition, dominant species, and abundance of phytoplankton were investigated in the northern Huanghai Sea between December 30, 2006 and January 17,2007. The results showed that 131 species were identified, belonging to 4 phyla with 68 genera ,in which 86.3% were Bacillariophyta （53 genera and 113 species） and 12.2% were Pyrrophyta（11 genera and 16 species）. The majority of species were neritic and cosmopolitan in temperate coastal seas. The average quantity of phytoplankton was 88.89 ×10^4 cells/m^3 , Bacllariophyta and Pyrrophyta were 86.58 ×10^4 cells/m^3 and 2.28×10^4 cells/m^3 , respectively. The dominant species included Eucarnpia zodiacus, Paralia sulcata, Pseudo-nitzschia pungens,Chaetoceros densus ,Chaetoceros debilis, Rhizosolenia setigera. In addition, the average diversity index （H＇） and evenness（J＇） values were 1.80 and 0. 42 , respectively. It was found that the coastal waters of southern Liaoning was the area of highest phytoplankton abundance, followed by the coastal waters of northern Shandong and the central area of the northern Huanghai Sea. The horizontal distribution of phytoplankton was determined by the diatom distribution pattern. In comparison with the investigation of Jan. 1959 ,the abundance of phytoplankton reduced nearly 41% （from 150.00×10^4 cells/m^3 to 88.89 ×10^4 cells/ m^3） ,among which the abundance of diatoms reduced from 148. 00 ×10^4 cells/m^3 to 86.58 ×10^4 cells/m^3, while the abundance of dinoflagellates increased from 1.25 ×10^4 cells/m^3 to 2.28 ×10^4 cells/m^3 （from 0.8 % to 2.5 %）. The community pattern relating to diatoms as the dominant group, followed by dinoflagellates, as well as the phytoplankton abundance, has not significantly changed irrespective of the above differences.