Relationships Between Community Structure and Environmental Factors in Xixiakou Artificial Reef Area

The construction of artificial reefs has unparallelly developed for a few decades in China.Artificial reefs can be used to manage and conserve commercially exploited fish and crustacea.However,their suitability as ecological niche is poorly characterized.Therefore,in this study,we detected the seasonal variation of community biodiversity and the corresponding driving environmental factors.We also explored the relationships between dominant species and environmental factors to identify appropriate ecological niche areas.Different statistical analysis methods were used to assess species distribution within an artificial reef area in Xixiakou during nine sampling events in four seasons between 2017 and 2018.Non-metric multidimensional scaling(NMDS)and cluster analysis results indicated that the components of community can be divided into two clusters.Complexity of community,which is exhibited by species number,biodiversity,and catch per unit effort(CPUE),was significantly higher in summer than in other seasons.Generalized additive model(GAMs)results revealed the significant effects of temperature and chlorophyll a on the community structure.Sebastes schlegelii,Hexagrammos otakii,Conger myriaster and Charybdis japonica were the dominant species in four seasons.GAMs results indicated that temperature,dissolved oxygen(DO),pH and chlorophyll a affect the CPUE of dominant species significantly.The distinct suitable ecological niche for each dominant species was found in this study.For example,Charybdis japonica preferred to live in the area with 20.7–22.1℃,dissolved oxygen 7.07–7.15 mg L−1 and salinity 31.8–31.9.The results of this study are beneficial to resource conservation and fishery management.