Abstract
Offshore wind farms (OWFs) provide hard substrates that support fouling communities, enhancing local biodiversity and contributing to carbon cycling. This study assesses the effects of water depth and artificial reef deployment on the structure, biomass, and carbon stock of fouling communities attached to turbine foundations in an integrated OWF and marine ranching zone in Laizhou Bay, China. The investigation includes four water layers (surface, upper, middle, and bottom) and three site types: turbine foundation, trapezoidal reef, and arch-column reef areas. The results showed significant differences in biomass, community structure, and carbon stock across different depths and site types (p < 0.05). Biomass and species richness were higher at middle and bottom depths; turbine foundation area had higher biomass than both reef deployment areas. Among the 31 identified species, Magallana gigas and Amphibalanus reticulatus emerged as key contributors to overall biomass and carbon stock across the study sites. In addition, we observed interactive effects of water depth and site type on fouling communities. Our findings highlight the significant effect of the depth gradients and artificial reef deployment on the fouling community structure and carbon sequestration potential. The integration of artificial reefs with OWFs, as a form of multi-use of marine space, may help mitigate the risk of structural corrosion caused by biological fouling to some extent.