青岛崂山近岸海域浮游植物群落结构及其与环境因子的关系

Structure characteristics of phytoplankton community and the relationship with environmental factors in offshore area of Laoshan,Qingdao

2012年5月和8月对崂山近岸和流清河湾网箱增养殖区的浮游植物进行调查。结果显示,5月共检出浮游植物23属36种,细胞丰度变动范围为85.26×103～720.16×103cell/m3,夜光藻为优势种,数量占浮游植物总量的80%以上,受其影响,群落多样性较差,细胞丰度低。8月共检出浮游植物30属54种,细胞丰度变动范围为43.00×103～1116.27×103cell/m3,群落多样性较好,细胞丰度较低。对浮游植物群落进行聚类分析,5月相似性在60%以上,8月在50%以上。崂山近岸的浮游植物细胞丰度平均值均大于流清河湾网箱增养殖区,而多样性均值前者均小于后者;相关性分析显示,细胞丰度平均值与N/P均值呈显著负相关(r=-0.81,P<0.05),而多样性均值与其呈显著正相关(r=0.98,P<0.05),认为影响浮游植物细胞丰度和多样性的最关键限制因子是无机氮。

Phytoplankton at inshore area of Laoshan and Liuqing River Bay of Qingdao were investigated in May and August,2012.There were 36species belonging to 23genera of phytoplankton collected during the survey in May,and the total number of phytoplankton was 85.26×10^3～720.16×10^3cell/m^3.An outbreak of Noctiluca scintillans was observed in May,when its cell number was more than 80%of the total cell count.The diversity index was influenced by N.scintillans,and the cell abundance was also low.In August,Fifty-four species belonging to 30genera of phytoplankton were collected during the survey;the total number of phytoplankton was 43.00×10^3～1 116.27×10^3cell/m^3.In August,phytoplankton was morediverse in survey areas,and the cell abundance was lower.Clustering analysis showed that the similarity of the phytoplankton community was more than 60%in May,and more than 50%in August.The cell abundance of phytoplankton at inshore area of Laoshan was more than that in Liuqing River Bay,while the diversity of the former was lower than the latter.Average cell abundance showed a negative correlation with N/P（r=-0.81,P0.05）,while the mean diversity showed a positive correlation with N/P（r=0.98,P0.05）.It is concluded that the key limiting factor affecting the cell abundance and diversity of phytoplankton was the inorganic nitrogen.