春季刘公岛南部海域浮游生物群落特征

Plankton Community Structure in the South of Liugong Island in Spring

利用2014年4月在威海刘公岛南部毗邻海域获取的生物样品,研究了该海域叶绿素a浓度分布趋势,以及浮游生物的种类组成、丰度分布、优势种和群落多样性。结果显示,调查海域表层叶绿素a浓度平均值(9.51μg/L)高于底层(8.97μg/L),表层叶绿素a浓度分布趋势呈现为由近岸向外海逐渐增加。本次调查共记录浮游植物25属41种,其中硅藻21属36种,占浮游植物总种数的87.8%;甲藻4属5种,占总种数的12.2%。调查海域硅藻(3.16×105 cells/m3)和甲藻(0.52×105 cells/m3)的平均丰度分别占浮游植物总丰度(3.67×105cells/m3)的85.9%和14.1%。硅藻在浮游植物物种数和丰度上都占显著优势。浮游植物优势种为威氏圆筛藻(Coscinodiscus wailesii)、丹麦细柱藻(Leptocylindrus danicus)、新月菱形藻(Nitzschia closterium)、长菱形藻(N.longissima)、柔弱几内亚藻(Guinardia delicatula)和夜光藻(Noctiluca scientillans)。该海域浮游动物共记录18种、浮游幼虫7类,合计共25种。其中浮游动物成体分别隶属于刺胞动物(3种)、甲壳动物(桡足类9种,端足类3种、糠虾1种)和毛颚动物(2种)。调查海域桡足类在浮游动物种类和丰度上占优势,平均丰度占浮游动物总丰度的40.3%。浮游动物优势种为双毛纺锤水蚤(Acartia bifilosa)、腹针胸刺水蚤(Centropages abdominalis)、中华哲水蚤(Calanus sinicus)、钩虾(Gammaridea)和长尾类幼体(Macrura larva)。

We characterized the community structure of plankton in the waters to the south of Liugong Island,sampled in April,2014.The average concentration of chlorophyll a in the surface(9.51μg/L)was higher than that in the bottom water(8.97μg/L).Chlorophyll a was elevated with increasing offshore distance.By microscopic analysis,a total of 45 phytoplankton species representing 24 genera were identified,among which 36 species representing 21 genera were diatoms and 5 species representing 4 genera were dinoflagellates.Diatoms and dinoflagellates account for 85.9%and 14.1%of the phytoplankton abundance,respectively,which was 3.67×105 cells/m3,in average in the surveyed waters.The dominant phytoplankton species were Coscinodiscus wailesii,Leptocylindrus danicus,Nitzschia closterium,N.longissima,Guinardia delicatula and Noctiluca scientillans.A total of 25 zooplankton species including planktonic larva(7 species)were identified.Among these,3 species of cnidarians,13 species of crustaceans and 2 species of chaetognaths were identified as adults.The dominant species of zooplankton were Acartiabifilosa,Centropages abdominalis,Calanus sinicus,Gammaridea and Macrura larva.