桑沟湾浮游纤毛虫丰度和生物量分布的季节变化

Seasonal variation of planktonic ciliates in Sanggou Bay , Huanghai Sea

于2011年4、8、10月及2012年1月对桑沟湾进行了浮游纤毛虫丰度和生物量的季节调查。纤毛虫的平均丰度为(7 552±10 979)个/L,范围为408～61 667个/L;纤毛虫的平均生物量(以碳计)为(4.79±5.77)μg/L,范围为0.35～33.09μg/L。无壳纤毛虫丰度和生物量主要分布在湾内,湾中和湾外丰度相对较低;砂壳纤毛虫丰度和生物量在盐度较高的海区总体较高,呈现朝向外海分布的趋势。纤毛虫丰度和生物量的高值区春季主要出现在湾的西北,夏季向湾中部迁移,秋季主要出现在湾的西南,冬季主要出现在湾的西部,高值区随季节大致呈顺时针迁移的趋势。纤毛虫的丰度春季最高,冬季最低;生物量夏季最高,冬季最低。无壳纤毛虫夏季粒级较大,冬季粒级较小;砂壳纤毛虫壳的平均口径夏季较大,秋季较小。共鉴定出砂壳纤毛虫8属27种,其中拟铃虫属(Tintinnopsis)种数最多。砂壳纤毛虫在纤毛虫总丰度中的比例平均为16.3%±21.9%,夏季最高(36.3%±27.8%),冬季最低(4.9%±5.9%)。纤毛虫丰度与温度、盐度、Chl a浓度及微微型真核浮游生物丰度均没有明显的相关性,但与蓝细菌及异养细菌丰度呈显著的正相关关系。

We investigated the abundance and biomass of planktonic ciliates in Sanggou Bay,Huanghai Sea during 4 cruises between April 2011and January 2012.The average abundance of ciliates was（7 552±10 979）ind/L,ranging from 408ind/L to 61667ind/L.The average biomass of ciliates（C）was（4.79±5.77）μg/L,ranging from 0.35μg/L to 33.09μg/L.Abundance and biomss of aloricate ciliates decreased from the inner part to the outer part of Sanggou Bay.Tintinnids had a seaward distribution,tending to concentrate in the regions with higher salinity.High value area of total ciliate abundance and biomass moved clockwise seasonally.Ciliate abundance was highest in spring and lowest in winter.Ciliate biomass was highest in summer and lowest in winter.Larger aloricate ciliate species were more prevalent in summer,while smaller species increased their proportion of total abundance in winter.Average lorica oral diameter of tintinnids was larger in summer and smaller in autumn.Twenty seven tintinnid species were identified,13of which were in genus Tintinnopsis.Tintinnids occupied 16.3%± 21.9%of the total ciliate abundance,being highest in summer and lowest in winter.Ciliate abundance showed no correlation with temperature,salinity,Chl a concentration and picoeukaryotes abundance,however,it showed significant positive correlations with abundance of Synechococcus and heterotrophic bacteria.