南极普里兹湾及其毗邻南印度洋夏季微小型浮游植物的分布特征

DISTRIBUTION CHARATERISTICS OF NANO-AND MICRO- PHYTOPLANKTON IN PRYDZ BAY AND ITS ADJACENT SOUTH INDIAN OCEAN,ANTARCTICA IN SUMMER

1990年 1 2月～ 1 991年 1月从南极普里兹湾及其毗邻南印度洋获得的微小型浮游植物样品 ,经鉴定、分析表明 :调查海区有 5门 40属 1 2 2种、变种和变型 ,其中硅藻类占 73 .0 %,甲藻类占2 0 .5 %,其它仅占 6 .5 %。表层水样微小型浮游植物平均丰度为 2 5 5 1× 1 0 4个 /m3 ,其密集区主要分布在普里兹湾内邻近陆架区的 7站和西冰架与沙克尔顿冰架之间的以北海域 ( 3、 4、 2、 3、 1站及 1站 ) ;位于普里兹湾西北部海域断面 和 1～ 5站丰度最低。网采浮游植物平均丰度为 81 2× 1 0 4 个 /m3 ,其密集区则分布在普里兹湾邻近陆架区 ( 2、 4、 5、 7、 4、 5站 )和西冰架北部海域 ( 1、 3站 ) ;低丰度位于沙克尔顿冰架东部海域 (断面 、 的测站 )。微小型浮游植物垂直分布密集区位于测区中部 ( 3、 3站 )和东部 ( 3站 ) 0～ 5 0 m水体 ,水深1 0 0 m以下至 2 0 0 m随深度的增加而丰度逐渐减少。微小型浮游植物丰度与大磷虾的丰度和营养盐 (N、P、Si)浓度成显著的负相关。

Phytoplankton samples were collected from 34 stations in Prydz Bay and its adjacent South Indian Ocean,Antarctica during a period from December 1990 to January 1991.122 taxa belonging to 40 genera 5 phyla were identified,of which,percentage of diatoms was 73%,dinoflagellates was 20.5%,the other species 6.5%.The average cell abundance of nano- and microphytoplankton was 2551×10 4 cells/m 3 in surface waters.The concentration area of nano- and microphytoplankton occurred in Prydz Bay and its adjacent continent station Ⅳ7 and northern water area between West Ice Shelf and Shackleton Ice Shelf(Stations Ⅶ3,Ⅷ1,Ⅷ2,Ⅷ3,Ⅸ1,and Ⅺ1); and minimal abundance occurred in west northern water area of Prydz Bay (sector Ⅲ some stations and stations Ⅳ 1-5).The average cell abundance of nano- and microphytoplankton from net sample was 811.52 10 4 cells/m 3,of which,the concentration area occurred in adjacent continental waters off Prydz Bay (Stations Ⅳ2,Ⅳ4,Ⅳ5,Ⅳ7,Ⅴ4,Ⅴ5) and northern water area of West Ice Shelf (Stations 1 and 3); low abundance occurred in eastern water area of Shackleton Ice Shelf (at each station in sector Ⅹ and Ⅺ).Nano- and microphytoplankton maximum was usually found at the surface and above 50m depth,and gradually decreased with the water depth from 100m to 200m.the relationship of cell abundance of nano- and microphytoplankton with Euphausia superba density and N.P.Si.contnets was negative significance.