西格陵兰Disko湾表层沉积硅藻组合研究

STUDY ON DIATOM SURFACE SEDIMENT ASSEMBLAGES IN DISKO BUGT (BAY),WEST GREENLAND

本文分析了西格陵兰Disko湾的表层沉积物硅藻,发现并统计了分属于39个属的78个硅藻种及其变种。应用对应分析方法,对Disko湾表层沉积硅藻组合进行了分类:组合Ⅰ为Fragilariopsis cylindrus-Fragilariopsis oceanica组合,主要分布在西格陵兰Disko湾南部的近岸和外海处;组合Ⅱ为Detonula confervaceae休眠孢子-Thalassiosira nordenskioeldii组合,都分布在Dis-ko湾北部海域。其中,根据海流等环境要素的不同,组合Ⅰ又可进一步划分为两个亚区:组合Ⅰa为F.cylindrus-F.oceanica-Pauliella taeniata组合,主要分布于沿岸海区;组合Ⅰb为F.cy-lindrus-F.oceanica-Thalassiosira antarcticavar.borealis休眠孢子-Thalassiosiracf.antarcticavar.borealis组合,分布于外海区域。

This paper analyzed the diatoms in the surface sediments of Disko Bugt （bay） in West Greenland and totally 78 species and varieties of diatom are found. The surface sediment diatoms of Disko Bugt （bay） are divided into two assemblages by correspondence analysis. Assemblage I, Fragilariopsis cylindrus-Fragilariopsis oceanica is located in the southern coast and the center of Disko Bugt （bay）. Assemblage Ⅱ, Detonula confervaceae resting spore-Thalassiosira nordenskioeldii, is situated in the northern part of Disko Bugt （bay）, of which the temperature and salinity of sea-surface are lower. Furthermore, due to the differences in the surface circulation and water depth, Assemblage I is divided into two sub-assemblages. Assemblage Ia, F. cylindrus-F, oceanica-Pauliella taeniata, appears in the coastal area. Assemblage Ib, F. cylindrus-F, oceanica-Thalassiosira antarctica vat. borealis resting spore-Thalassiosira cf. antarctica var. borealis, is located in the center of Disko Bugt （bay）.