台湾海峡西部海域浮游桡足类的生态

ECOLOGY OF PLANKTONIC COPEPODS IN THE TAIWAN STRAIT

本文根据1984年5月—1985年2月在台湾海峡中线以西海域不(含海岸带水域)4个季度月综合调查及海潭岛南部外海定点昼夜垂直分层采集所获浮游动物样品进行分析,结果表明,本海域浮游挠足类188种(国内新记录7种,本海区首次记录19种),主要的优势种有锥形宽水蚤、中华哲水蚤、精致真刺水蚤、普通波水蚤等。其群落组成以热带和亚热带种为主,少数为暖温带种。根据其生态习性及分布特点可分为近岸低盐、外海高盐及广温广盐三个生态类群。海潭岛南部外海浮游挠足类的昼夜垂直移动可分为移动显著和不显著两种类型。本海区浮游桡足类种数的季节变化和平面分布均与温、盐度的变化趋势基本一致,其不同生态习性的浮游桡足类的分布与影响本海区的水系的消长密切相关。

One hundred and eighty-eight species of planktonic copepods were identified from 199 quantitative zooplanktonic samples,seasonally collected from the waters to the west of the central line of Taiwan Strait(coastal zone was excluded)from May,1984 to February,1985.Among them,7 species were first records in China Seas and 19 species wore first records in the studied waters,among them,the main dominant species were Temora turbinata,Calanus sinicus,Euchaeta concinna,Undinula vulgaris,T.discaudata,Canthocalanus pauper,Eucalanus crassus and E.subcrassus.Tropical and subtropical species account for,at least 95%of the community composition of planktonic copepods,the rest being warm-temperate species.According to their ecological habit and distribution,the planktonic copepods may be divided into three ecological groups,i.e.neritic low-salinity group,typical oceanic high-salinity group and eurysalinity and eurythermy group.The species number of the planktonic copepods was the highest(151 species)in spring,the lowest(102 species)in winter,and middle in summer and autumn(126 and 125 species respectively).However the high-peak of the total indibidual number was found in summer(102 ind./m^3);the low-peak in autumn(53 ind./m^3);and about the same in winter and spring(72 and 73 ind./m^3 respectively).The diurnal vertical migration of planktonic copepods off the south of Pingtan Island was in two patterns.Members of the first pattern moved down by day and up at night.Members of the second pattern were distributed respectively in middle-upper layer,middle-low layer,and whole water column.The species number of the planktonic copepods in the survey region,both in seasonal variation and horizontal distribution from the north to the south or from the neritic to the ocean,was about the same as the variation trend of temperture and salinity.The distribution of the different ecological habit copepods was closely related to the growth and decline of currents and water masses which exercise influences on the survey zone.