Abstract: This study evaluated the microbial diversity in the seawater of the Pearl Bay T. ovatus aquaculture area and its relationship with environmental factors, aiming to provide scientific support for optimizing the aquaculture environment and improving farming efficiency. Seawater samples were collected from March 2024 to February 2025, and microbial diversity was analyzed using high-throughput sequencing across different seasons and sampling sites. Results showed significant temporal and spatial variations in water physicochemical properties, with Proteobacteria as the dominant phylum (48.45%-53.20% relative abundance). Alpha diversity indices indicated significant differences between sites and seasons. Redundancy analysis (RDA) identified salinity, temperature, and nitrate as key environmental factors influencing microbial community structure, while nitrogenous nutrients were found to be the main drivers of community composition through Mantel tests and correlation analyses. Functional predictions via PICRUSt2 highlighted the predominant microbial functions in metabolic processes, genetic information processing, and cellular information processing. These findings underscore the complexity of microbial communities in Pearl Bay, shaped by various environmental factors, particularly nitrogenous nutrients. This study provides crucial data for marine aquaculture development and offers valuable insights for disease prevention and epidemiological studies in cage farming.

Key words: Pearl Bay, microorganisms, Trachinotus ovatus, environmental factors, correlation, high-throughput sequencing