大亚湾夏季表层浮游细菌生物量分布与环境变量的关系

Correlations Between Bacterioplankton Biomass Distribution and Environmental Variables in Surface Seawater Layer of Daya Bay in Summer

根据2008年夏季(7月)在大亚湾进行的现场综合调查资料,分析表层海水浮游细菌生物量的水平分布特征,探讨细菌生物量与环境变量的关系。大亚湾夏季浮游细菌生物量变化范围为14.00～118.80μg·L^(-1),海区平均值为55.23±29.43μg·L^(-1)。大亚湾夏季细菌生物量水平分布大体上呈现南部高于北部的趋势,在北纬22°35′以北和以南的海区均各自表现为东南部高于西北部的趋势。水深、硝酸盐、铵盐、亚硝酸盐和总碱度等5个参数与浮游细菌生物量之间存在着中等水平的相关性(0.15<P=0.05),表明这些参数能够对浮游细菌生物量分布产生不同重要程度的影响。大亚湾夏季表层浮游细菌生物量和浮游植物生物量的比值变化范围为0.29～3.10,该比值反映了该海区初级生产与细菌二次生产之间的数量大小关系。气候条件、水体交换和人类活动造成大亚湾不同海区复杂多样化的环境条件,从而能够影响大亚湾浮游细菌生物量的水平分布格局。

On the basis of the cruise in Daya Bay in summer(July)2008,the distribution patterns of bacterioplankton biomass were studied in surface layer in the subtropical bay.The relationships between bacterial biomass and environmental variables were analyzed.The results showed that the bacterial biomass ranged from 14.00 to 118.80μg·L^-1;and the mean bacterial biomass was 55.23±29.43μg·L^-1 Spatially,the bacterial biomass of station surface layers in south of the bay was higher than that in the north of the bay.In each marine areas located in the south or north of north longitude 22°35′in this bay,it was higher in southeast of the bay than in northwest of the bay.There existed moderate correlationships between five environmental parameters including depth,nitrate,ammonia,nitrite and total alkalinity(0.15<P=0.05),indicating the effects of different importance degree of these parameters on the distribution of bacterioplankton biomass.The ratio of bacterioplankton biomass and phytoplankton biomass in surface layer in Daya Bay in summer ranged from 0.29 to 3.10,which reflected the magnitude relationships between primary production and the second production by bacteria in this marine area.Climate conditions,water exchange and human activities cause complex and diverse environmental conditions in different sea areas of Daya Bay,which can affect the horizontal distribution pattern of bacterioplankton biomass in this bay.