南极夏季普里兹湾磷虾幼体及纽鳃樽的丰度和分布特征

DISTRIBUTION AND ABUNDANCE OF EUPHAUSIID LARVAE AND SALPS DURING AUSTRAL SUMMERS IN PRYDZ BAY,ANTARCTICA

根据2002年及2006年南大洋普里兹湾浮游动物和环境调查资料,对普里兹湾磷虾幼体及被囊类纽鳃樽的分布和丰度进行了初步研究。结果表明,陆架以北深海水域(水深>1000m)磷虾幼体主要由长臂樱磷虾Thysanoessa macrura和大磷虾Euphausia superba组成,其中长臂樱磷虾幼体的分布范围更广、丰度更高。2006年与2002年相比海冰回退时间早,测区海水的平均温度和叶绿素a浓度较高,大磷虾及长臂樱磷虾幼体的丰度相对更大,成熟度更高。近岸区域磷虾幼体主要由晶磷虾Euphausia crystallorophias组成,在2002年近岸冰情严重时丰度较小,仅为95.6尾/1000m3,2006年近岸出现冰间湖时,晶磷虾幼体丰度高达43966.6尾/1000m3,主要以无节幼体及原蚤状幼体CI期为主。测区纽鳃樽Salpa thompsoni丰度很低,2002年仅在最北部1个站位出现,密度为10个/1000m3,2006年在陆坡及陆架坡折3个站位出现,平均丰度为146.7个/1000m3。海冰消融时间、冰间湖、饵料浓度等环境因子对普里兹湾磷虾幼体及纽鳃樽的分布和丰度产生重要影响。

The distribution and abundance of euphausiid larvae and salps were studied based on zoo- plankton samples collected in 2002 and 2006 from Prydz Bay, Antarctica. Larvaes of Thysa- noessa macrura and Euphausia superba were mainly distributed in the north of the continental shelf. Thysanoessa macrura was more abundant with relatively wider distribution area than Eu- phausia superba. In the year 2006 with earlier ice retreating, higher seawater temperature and chlorophyll a level, Euphausia superba and Thysanoessa macrura presented higher abundance and older developmental stage. Euphausia crystallorophias was mainly distributed in the neritic region. In the year 2002 with serious ice conditions in the neritic region, the abundance of Euphausia crystallorophias was only 95.6 ind/1000 m^3. In the year 2006 when polynya existed, the abundance of Euphausia crystallorophias reached 43966.6 ind/1000 m^3, and the population was mainly composed of metanauplius （MN） and ealyptopis I （CI）. Salps, mostly composed of Salpa thompsoni, had a low abundance in the Prydz Bay. In 2002, S. thompsoni was only found at one station of the north of the bay with the abundance 10 ind/1000 m^3. In 2006, S. thompsoni was found at three stations located near continental slope and its average abundance reached 146.7 ind/1000 m^3. The research suggested that the distribution and abundance of eu- phausiid larvae and salps have good accordance with the environmental factors.