2007年夏季南海北部浮游植物的物种组成及丰度分布  

Species composition and abundance of phytoplankton in the northern South China Sea in summer 2007

作　　者：柯志新[1] 黄良民[1] 谭烨辉[1] 尹健强[1] 

机构地区：[1]中国科学院海洋生物资源可持续利用重点实验室,广东广州510301

出　　处：《热带海洋学报》2011年第1期131-143,共13页Journal of Tropical Oceanography

基　　金：中国科学院知识创新工程重要方向项目(KZCX2-YW-213);中国科学院南海海洋研究所青年人才基金项目(SQ200907);国家-广东联合基金(U0633007)

摘　　要：2007年8月10—29日对南海北部41个站位进行了浮游植物群落结构的调查。调查结果表明,共发现浮游植物5门80属216种(包括变种、变形、未定种),调查期间南海浮游植物以硅藻为主,占所有物种数的64.81%,占总浮游植物细胞丰度的89.11%;甲藻次之,占所有物种数的30.56%,占总浮游植物细胞丰度的10.62%;蓝藻门的红海束毛藻Trichodesmium erythraeum在许多站位也占有相当的比例。绿藻和一些淡水的蓝藻只在珠江口附近的站位才被检出。主要优势种为海链藻Thalassiosira sp.、菱形海线藻Thalassionema nitzschioides、中肋骨条藻Skeletonema costatum、微小原甲藻Prorocentrum minimum和裸甲藻Gymnodinium sp.。从平面分布来看,南海北部在珠江口外围和台湾浅滩海域存在2个浮游植物丰度高值区。表层和次表层浮游植物的平面分布格局差异很大,表层浮游植物的丰度平均为25.21×103个.L?1,高值区在珠江口附近海域;次表层浮游植物丰度平均为9×103个.L?1,高值区在台湾浅滩海域。调查区域的浅水站位(<200m)的浮游植物丰度远高于深水站位(>200m)。从垂直分布来看,浮游植物的细胞丰度基本上自上而下随水深的增加而逐渐降低,最大丰度在10m水层。深水站位与浅水站位的浮游植物垂直分布结构有很大的差异。硅藻类在浅水站位中基本随深度的增加而减少,但在10m处出现最大值;而在深水站位则存在次表层(75m)最大值的现象。甲藻类在浅水站位中随深度增加显著减少,而在深水站位的75m以上其分布比较均匀。越靠近外海,浮游植物中硅藻所占的比例越小,硅甲藻比率大的海区一般具有高的生产力和较高的浮游植物丰度。调查海区表层和次表层的浮游植物Shannon-Wiener指数的平均分别为2.8和3.0,生物多样性高的区域分别位于珠江口、粤东近海和海南的东部近海,浅水站位的浮游植物多样性指数远高于深水站位。We investigated the abundance and species composition of phytoplankton community in the northern South China Sea（110°-120°E,18°-23°N） from 10th to 29th August 2007,using 208 samples taken from 41 sampling stations.A total of 216 species belonging to 80 genera of 5 classes were identified.Diatoms contributed to 64.81% of the total phytoplankton species number and 89.11% of the total phytoplankton cell abundance;followed by dinoflagellates,which accounted for 30.56% of total phytoplankton species number and 10.62% of the total phytoplankton cell abundance.The dominant species were Thalassiosira sp.,Thalassionema nitzschioides,Skeletonema costatum,Prorocentrum minimum and Gymnodinium sp..Trichodesmium erythraeum that belonged to Cyanophyta was also commonly found at many survey stations.High phyto-plankton cell abundance was located in the Pearl River Estuary and in Taiwan Shoal.The horizontal distribution pattern of phytoplankton abundance was different in the surface and sub-surface waters.In the surface water,the average abundance of phytoplankton was 25.21×103cells.L？1 with a high value near the Pear River Estuary;while in the sub-surface water,the aver-age abundance was 9×103cells.L？1 with a high value in the Taiwan Shoal.On the whole,phytoplankton abundance was lower at deep-water stations（200m） than at shallow-water stations（200m）.In general,the vertical profiles showed that total phytoplankton abundance presented a peak at 10m and then decreased with increasing water depth.The vertical distribution patterns of phytoplankton abundance also appeared to be different between deep-water and shallow-water stations.Diatoms abundance decreased with increasing water depth at the shallow-water stations,but formed a maximum peak at sub-surface（75m） of the deep-water stations;dinoflagellates abundance significantly decreased with increasing water depth,but evenly distributed in the water above 75m at the deep-water stations.The ratios of diatom to dinoflagellates showed a decline ten-dency appr

关 键 词：南海北部 浮游植物 物种组成 细胞丰度 生物多样性 

分 类 号：P735.1[天文地球—海洋生物学]