填海工程对海洋沉积物微生物群落的影响

为了解海域微生物的群落结构和空间差异,探究其与环境的潜在联系,选择大型石化基地浙江舟山市鱼山岛海域,以期为我国海洋工程建设的环境管理提供技术支撑。在基地建设围填海时期,设置10个海域生态监测站,按《海洋监测规范》和《海洋调查规范》对海域沉积物进行取样调查。结果显示,海域环境明显受到长江、钱塘江等入海河流的影响,有机碳(TOC)、石油类(Oil)、砷(As)、镉(Cd)、铜(Cu)和铅(Pb)均在海域西北形成高值区,并逐步向东部海域递减。应用Illumina MiSeq宏基因组高通量测序技术,在海域沉积物中鉴定得到古菌和细菌共39门、260科、431属。从门水平上看,变形菌门(Proteobacteria)在各站位均表现出明显优势,其相对丰度占总数的39%;其它较为丰富的门类包括放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)、绿弯菌(Chloroflexi)、拟杆菌门(Bacteroidetes)和泉古菌(Crenarchaeota)。从属水平上看,Gamma变形菌是最主要的优势菌,其它主要种类还有Deltar变形菌、拟杆菌、放线菌、酸杆菌、浮霉菌(Planctomyces)、Beta变形菌和黏球菌(Myxococcus),Delta变形菌成为微生物群落的主要种类之一,显示海域环境一定程度地受到了沿岸人类活动的影响。微生物与环境因子的相关性分析表明,有机碳、砷和底栖生物对微生物门水平的群落分布具有显著性影响,奇古菌、黏胶球形菌和P-SR1与石油类、砷、铅、镉等重金属呈显著负相关。

Effects of Reclaiming Land from the Sea on the Microbial Communities of Marine Sediments

Engineering construction and land reclamation have changed the natural forms of coastlines, coastal bays and estuaries, affected the hydrodynamic environment and altered seabed erosion and deposition, resulting in serious ecological problems. A petrochemical complex was planned for construction on Yushan Island of Zhoushan City and reclamation of land from the sea was carried out to create the industrial base. In this study, we analyzed the microbial community structure and spatial divergence in sediments of the marine area around the land reclamation project and identified potential links of the microbial community to environmental factors. The objective was to provide technical support for marine construction projects, coastal economic development and environmental management. In May 2016, the environmental factors and microbial communities were investigated at 10 monitoring sites, according to specifications for marine monitoring and oceanographic surveys. The marine environment was impacted by river influxes, including inputs from the Yangtze and Qiantang Rivers. Total organic carbon (TOC), petroleum, arsenic (As), cadmium (Cd), copper (Cu), and lead (Pb) were at higher levels in the northwestern area and decreased toward the east. Metagenomic analysis, using Illumina Miseq high throughput sequencing technology, identified a total of 39 phyla, 260 families and 431 genera of archaea and bacteria in the sediment samples. At the phylum level, Proteobacteria was the dominant taxa at all sampling sites, comprising 39% of the total abundance. Other abundant taxa included Actinobacteria, Acidobacteria, Chloroflexi, Bacteroidetes, and Crenarchaeota. At the genus level, Gammaproteobacteria was the dominant group and other major genera included Deltaproteobacteria, Actinomyces, Planctomyceteschus and Myxococcus. Further, Deltaproteobacteria became one of the major components of the microbial community, indicating that the study area was affected by human activities. Correlation analysis between the microbial community and environmental factors revealed that TOC, arsenic and marine benthic animals significantly affected microbial community distribution at the phylum level. The abundance of Thaumarchaeota, Lentisphaerae, and P-SR1 presented significantly negative correlations with petroleum, As, Pb and Cd.