南极中山站近岸海冰生态学研究Ⅲ.冰藻优势种的季节变化及其与冰下浮游植物的关系

自１９９２年４月１２日至１２月３０日对中山站以西内拉峡湾海冰和冰下水柱中藻类优势种组成和丰度进行了测定。４月份和１１月中旬至１２月中旬冰柱和水柱（０～５０ｍ）藻类丰度高达１０８～１０９ｃｅｌｓ／ｍ２。冰藻的普遍或季节性优势种主要包括Ａｍｐｈｉｐｒｏｒａｋｊｅｌｍａｎｉ、Ｂｅｒｋｅｌｅｙａｒｕｔｉｌａｎｓ、Ｎａｖｉｃｕｌａｇｌａｃｉｅｉ、Ｎｉｔｚｓｃｈｉａｂａｒｋｌｅｙｉ、Ｎ．ｃｙｌｉｎｄｒｕｓ、Ｎ．ｌｅｃｏｉｎｔｅｉ和Ｎｉｔｚｓｃｈｉａｓｐ．。由于藻类结合入冰后自身的演替，春－夏季海冰剖面中所记录的优势种组成并不能准确反映冰底优势种的季节演替过程。从冰底和水表藻种组成的对比表明，两者仅在春末冰底冰藻水华期间具有较强的相似性。秋、春季冰底冰藻水华的形成以现场生长为主，夏初冰藻释放入水后对冰下浮游植物的播种作用不明显。

SEASONAL CHANGE OF ICE ALGAL ASSEMBALGES WITH ITS RELATION TO PHYTOPLANKTON NEAR ZHONGSHAN STATION,EAST ANTARCTICA

The ice algal and phytoplankton assemblages were monitored from April to December,1992 in Nella Fjord near Zhongshan Station (69°22′24″S,76°22′40″E),east Antarctica.The abundance of algae in the ice and water column (0～50 m) were higher in April and mid November mid December,which could reach 10 8-10 9cells/m 2. Amphiprora kjellmanii、Berkeleyarutilans、Navicula glaciei、Nitzschia barkleyi、N.cylindrus、N.lecointei and Nitzschia sp.were dominant in the ice column in one season or throughout the study.Although the dominant species could maintain in some ice layers,succession occurred in most sections following the changes of the environmental factors.The dominant species in the vertical profiles of ice in the spring and summer couldn't reflect the seasonal succession of blooms in the bottom layer of ice. The comparison of algal composition and abundance between bottom layer of ice and surface layer of water suggests that it is different except in late November when the spring ice algal bloom occurred.Both autumn and spring ice algal blooms occurred mainly by the in situ growth rather than physical collection.The seeding of ice algae to phytoplankton was not significant after they released from ice in early December.