摘要
为探究海洋聚球藻(Synechococcus)生态类群在近岸上升流区精密空间尺度上的分布特征及共存关系,采用16S~23S rDNA内转录间隔区(internal transcribed spacer,ITS)定量聚合酶链式反应(qPCR)技术,对南海西北部琼东上升流区夏季水体中的10个聚球藻主要分型的水平和垂直空间分布特征进行了分析。结果表明:10个聚球藻主要分型在琼东上升流水体中广泛分布,在水平和垂直方向上具有明显的空间分布特征;Ⅱ、Ⅲ、Ⅹ和CRD1(Costa Rica Dome)型聚球藻为优势类群,其中Ⅱ型聚球藻平均丰度最高;Ⅱ、Ⅲ、Ⅳ和Ⅹ型聚球藻在琼东上升流表层水体中呈现高丰度分布且存在共存关系,其中Ⅱ、Ⅲ和Ⅳ型聚球藻的丰度呈现出等值线向近岸次表层水体明显抬升,且与温度和溶解氧(dissolved oxygen,DO)呈正相关,与盐度呈负相关,说明上升流动力过程影响了Ⅱ、Ⅲ和Ⅳ型聚球藻在琼东海域的分布及共存;Ⅰ、Ⅷ和Ⅹ型聚球藻的丰度在近岸河口表层水体中达到峰值,三者主要受到河流径流的影响,而上升流动力过程对其影响不大;CRD1、CRD2、ⅩⅤ和ⅩⅥ型聚球藻在琼东海域次表层水体的分布存在共现性,但从整体上看,其与温度、DO及盐度相关性不大。研究表明,聚球藻不同生态类群在琼东上升流区占据不同生态位,温度、盐度、DO、上升流动力过程及河流径流是影响聚球藻不同生态类群生态位分化的重要因素,该研究结果为深入研究海洋聚球藻各生态类群的功能提供了科学参考。
In order to explore the distribution characteristics and coexistence relationship of marine Synechococcus assemblage on the precise spatial scale in the coastal upwelling area from 18°30′-20°30′N to 110°00′-111°30′E,the horizontal and vertical spatial distribution of ten clades of Synechococcus was investigated in the water of the Qiongdong upwelling area in the northwest of the South China Sea in summer by 16S-23S rDNA internal transcribed spacer(ITS)quantitative polymerase chain reaction(qPCR)technology.The results showed that the ten clades of Synechococcus were widely distributed in Qiongdong upwelling water,and presented obvious spatial niche partitioning in the horizontal and vertical directions.The dominant clades wereⅡ,Ⅲ,Ⅹand CRD1(Costa Rica dome),and the maximal average abundance of all the ten Synechococcus was cladeⅡin the Qiongdong upwelling water.TypesⅡ,Ⅲ,ⅣandⅩwere highly abundant in the surface water and coexisted with each other.The isolines of cladesⅡ,ⅢandⅣabundances were significantly elevated to the near-shore subsurface water,with positively correlated with temperature and dissolved oxygen(DO)level,and negatively correlated with salinity,reflecting the influence of upwelling dynamic processes on their coexistence.There was the peak abundance of cladesⅠ,ⅧandⅩin the surface water of the coastal estuary,which was mainly affected by river runoff.The distribution of CRD1,CRD2,ⅩⅤandⅩⅥtypes in the subsurface water of Qiongdong area were co-occured,without significant correlation relationship with temperature,DO and salinity on the whole.There were different ecological clades of Synechococcus in different niches.Temperature,salinity,DO,upwelling dynamic process and river flow affected the different niche partitioning of Synechococcus assemblage in the Qiongdong upwelling area.The findings provided theoretical foundation for further study on the function of marine Synechococcus assemblage.
作者
侯庆华
叶映仪
HOU Qinghua;YE Yingyi(Laboratory for Coastal Ocean Variation and Disaster Prediction,College of Oceanography and Meteorology,Guangdong Ocean University,Zhanjiang 524088,China)
出处
《大连海洋大学学报》
CAS
CSCD
北大核心
2023年第5期753-762,共10页
Journal of Dalian Ocean University
基金
国家自然科学基金(41706129)
广东省高校创新团队计划项目(2019KCXTF021)。
