Abstract：
Planktonic bacteria play a crucial role in sustaining the ecological balance of aquatic ecosystems. However, their seasonal variations in different aquaculture areas within the East China Sea, along with their correlation to environmental factors, have not been extensively explored. In this study, each area with 3 sample points were set up to represent the fish aquaculture area, shellfish aquaculture area and non-aquaculture area. In 2019, we undertook four marine surveys along the Xiasanhengshan uninhabited island, during which we gathered surface seawater samples for both physicochemical analysis and high-throughput sequencing. This allowed us to obtain data about the physicochemical properties and microbial composition in each surveyed region. A short-term eutrophication phenomenon was present in the sea, and the spatial and temporal distribution of planktonic bacteria differed based on the mariculture area. At the phylum level, Proteobacteria accounted for >50 % of the community abundance in winter, spring, and autumn, while Cyanobacteria accounted for >30 % of the community abundance in summer. Because Cyanobacteria blooms are likely in summer, the relationship between Cyanobacteria and environmental factors was studied. Redundancy analysis showed that Cyanobacteria were consistently positively correlated with phosphate. Eutrophication and abnormal proliferation of Cyanobacteria in the study area necessitate ameliorations in the mariculture structure. The variation of genus in Proteobacteria is consistent with that of eutrophication, so some genera in Proteobacteria have the potential to become biological indicator species.
摘要：
浮游细菌在维持水生生态系统的生态平衡中起着至关重要的作用。然而,它们在东海不同水产养殖区的季节变化，以及它们与环境因素的相关性，没有得到广泛的探索。在这项研究中,每个区域设置3个样本点代表鱼类养殖区，贝类养殖区和非养殖区。2019年，我们在下山恒山无人岛沿线进行了四次海洋调查，在此期间，我们收集了表面海水样品进行物理化学分析和高通量测序。这使我们能够获得有关每个调查区域的理化性质和微生物组成的数据。海洋中存在短期富营养化现象，浮游细菌的时空分布因海水养殖区而异。在门一级，变形菌占冬季群落丰度的50%以上,spring,秋天,而夏季蓝藻占群落丰度的30%以上。因为蓝细菌很可能在夏天出现，研究了蓝藻与环境因子的关系。冗余分析表明，蓝细菌与磷酸盐始终呈正相关。研究区蓝藻的富营养化和异常增殖需要改善海水养殖结构。变形杆菌属的变异与富营养化一致，所以变形杆菌中的一些属有可能成为生物指示物种。
