Assessing the impacts of fishing on fish community in marine ranch of the Wuzhizhou Island based on size-spectrum model
The concept of ecosystem-based fisheries management has been widely recognized,but it's application in the construction of marine ranch is still very rare.In this study,based on the data from a bottom trawl survey of fishery resources conducted in the waters of Wuzhizhou Island from 2020 to 2021,a marine ranch fish community size-spectrum model(SSM)was built,which reflects the complex structure of food webs and interspecies interac-tions in marine ranch,to assess the impacts of fishing on the fish community in marine ranch.The study analyzed the effects of changes in species-specific fishing death coefficient on fish community by simulating two manage-ment strategies(single-species management and multispecies management)and monitored the state of fish com-munity characteristics using five community ecological indicators:the total biomass of the community,the slope of size spectrum,the mean maximum weight,the mean weight,and the large fish index.The results of the single-spe-cies management strategy showed that the marine ranch ecosystem of Wuzhizhou Island showed top-down control,and there was a strong regulatory effect of carnivorous fish on plankton-feeding fish.Complex interactions such as competitive predation among different species produce trophic cascade effects after changes in fishing death coeffi-cient.The results of the multispecies management strategy showed that fishing death coefficient of Muraenesox cinereus had the greatest effect on the slope of size spectrum,and that fishing death coefficient of Trachiocephalus myops and Muraenesox cinereus had the greatest effect on fish community biomass and community structure and function.The results of this study have important implications for the conservation and stabilization of fish com-munity,and can help managers to better understand the potential impacts of changes in fishing death coefficient rates on fish communities,so that viable and effective conservation and management strategies can be developed based on the importance of the species to the fishery.
万方数据
维普
