随着全球牡蛎养殖规模的不断扩大，牡蛎养殖对海洋环境及海底沉积物的影响引起了研究者的关注。已有大量研究证明，牡蛎养殖可以通过影响底泥中有机氮的氨化、硝化和反硝化作用，改善沉积物氮循环。然而，针对磷循环，目前还缺乏相关的研究数据，特别是在城市化的内湾。磷是海洋生态中重要的营养元素，是海洋食物网重要的基础元素，沉积物再悬浮导致的沉淀磷释放，是海湾中磷的重要来源之一。因此，对牡蛎养殖条件下沉积物磷循环的研究显得非常迫切。本研究分层采集了牡蛎养殖区和对照区的沉积物样品，对两个区域沉积物的理化性质、磷赋存状态及微生物组成进行了比较，并利用Geochip5.0高通量基因芯片，从功能角度探究了养殖区与对照组沉积物中微生物功能的异同，借此分析了牡蛎养殖对沉积物磷代谢的具体影响及其机理。实验结果表明，牡蛎养殖的引入使海底沉积物更加疏松多孔，颗粒细致均匀，增加了沉积物-上覆水界面营养交换效率。与对照区相比，牡蛎养殖区总磷含量更高，游离态有机磷浓度显著降低，游离态无机磷和Fe/Al-P浓度显著升高（p<0.05），说明牡蛎养殖提高了养殖区沉积物对磷营养的获取效率，同时改变了磷的组成形态，促进了有机磷向无机形态转化，使一些难以生物利用的磷转化为更加有效的形态（更易被生物利用）。对微生物群落的研究中，非度量多维尺度分析（Non-metric Multidimensional Scaling，NMDS）结果表明，养殖区沉积物中微生物组成与非养殖区沉积物具有显著的不同（PERMANOVA, R2 =0.44, p<0.05）。微生物多样性分析及网络分析结果表明，牡蛎养殖提高了底泥中微生物群落的α多样性，降低了微生物群落的均匀性；且养殖环境下微生物网络中各物种正负反馈比例更加均衡，群落网络更加成熟。为了探讨磷代谢改变的微生物学机制，采用Geochip5.0芯片对微生物功能基因进行了深入的检测。结果显示，养殖区和对照区的主要磷循环途径，包括磷降解、多聚磷酸盐合成、多聚磷酸盐降解及磷转运等通路存在显著差异（p<0.05）。牡蛎养殖不仅促进了有机磷向无机磷的转化，而且提高了无机磷进入生态循环的效率。综上所述，牡蛎养殖能够改良城市化内湾的沉积物性质，并通过微生物作用改善深圳湾沉积物内的磷循环状况，帮助我们更好地理解牡蛎养殖过程对沉积物的改善及其对微生物磷循环的激发作用。

With the continuous expansion of the global scale of oyster culture, the impact of oyster culture on the marine environment and seafloor sediments has attracted the attention of researchers. A large number of studies have proved that oyster culture can improve sediment nitrogen cycle by affecting the ammoniation, nitrification and denitrification of organic nitrogen in sediment. However, for the phosphorus cycle, there is still a lack of relevant research data, especially in the inner bay of urbanization. Phosphorus is an important nutrient element in marine ecology and an important basic element in marine food webs. The release of precipitated phosphorus caused by sediment resuspension is one of the important sources of phosphorus in the bay. Therefore, it is very urgent to study the phosphorus cycle of sediment under the condition of oyster culture.In this study, sediment samples from oyster culture area and control area were collected by stratification, and the physical and chemical properties, phosphorus occurrence state and microbial composition of sediments in the two areas were compared. Geochip5.0 high-throughput gene chip was used to explore the similarities and differences of microbial function between oyster culture area and control area, so as to analyze the specific effect of oyster culture on sediment phosphorus metabolism and its mechanism.The experimental results show that the introduction of oyster culture makes the seafloor sediments more loose and porous, the particles are fine and uniform, and increases the efficiency of nutrient exchange at the sediment-overlying water interface. Compared with the control area, the content of total phosphorus in oyster culture area was higher, the concentration of free organic phosphorus decreased significantly, and the concentration of free inorganic phosphorus and Fe/Al-P increased significantly (p<0.05), indicating that oyster culture improved the efficiency of phosphorus acquisition by sediments in oyster culture area, changed the composition of phosphorus and promoted the transformation of organic phosphorus into inorganic form. Convert some phosphorus that is difficult to biouse into more efficient forms (more easily used by organisms). In the study of microbial community, the results of NMDS analysis showed that the microbial composition of sediments in aquaculture area was significantly different from that in non-aquaculture area (PERMANOVA, R2=0.44, p<0.05). The results of microbial diversity analysis and network analysis showed that oyster culture increased the α diversity of microbial community in sediment and decreased the uniformity of microbial community, and the proportion of positive and negative feedback of each species in microbial network was more balanced and the community network was more mature.In order to explore the microbiological mechanism of phosphorus metabolism changes, Geochip5.0 microarray was used to detect the functional genes of microorganisms. The results showed that there were significant differences in the main phosphorus cycle pathways, including phosphorus degradation, polyphosphate synthesis, degradation and phosphorus transport between the culture area and the control area (p<0.05). Oyster culture not only promoted the transformation of organic phosphorus to inorganic phosphorus, but also improved the efficiency of inorganic phosphorus entering the ecological cycle.To sum up, oyster culture can improve the sediment properties of the urbanized inner bay and improve the phosphorus cycle in the sediments of Shenzhen Bay through the action of microorganisms. It helps us to better understand the improvement of sediment and the stimulating effect of oyster culture on microbial phosphorus cycle.