广东外伶仃海洋牧场及邻近海域鱼类功能多样性与环境驱动OACHSSCD

[Objective]This study aims to investigate the dynamic characteristics and driving mechanisms of fish community diversity in the Wailingding National Marine Ranching Demonstration Zone,Guangdong Province,and provide a scientific basis for assessing ecological health and optimizing fishery management.[Method]Four cruises were conducted in April 2020,September 2020,September 2021,and March 2023 to investigate fishery resources and environmental factors.Species diversity and functional diversity indices were calculated,and seasonal variations in fish communities and their relationships with environmental factors were discussed through Redundancy Analysis(RDA)and Mantel correlation analyses.[Results]The asynchronous trends were found between species diversity and functional diversity.Although the species richness index peaked in September 2021(3.495),the functional richness index(FRic)was significantly lower than that in other sampling periods(P<0.01).Spearman correlation analysis indicated a highly significant negative correlation between functional redundancy(FRed)and Pielou index(P<0.01),due to the community's maintenance of high functional redundancy throughout the survey period.RDA and Mantel analyses revealed that chlorophyll-a concentration and pH were the primary drivers of functional richness,while water depth significantly affected functional divergence(FDiv)(P<0.01).[Conclusions]The fish community in the Wailingding marine ranching adapts to environmental fluctuations primarily through high functional redundancy.Chlorophyll-a concentration,pH,and water depth are the key environmental factors driving functional diversity patterns.Monitoring based on functional traits can more accurately reflect the ecological health of marine ranching ecosystems.