Assessment of the local environmental impact of intensive marine shellfish and seaweed farming-Application of the MOM system in the Sungo Bay, China

摘要

The impact of large scale shellfish (Crassostrea gigas, Chlamys farreri) and seaweed (Laminaria japonica) culture on the benthic environment at the Sungo Bay, China was assessed using the B-investigation of the MOM system. The MOM system (Modelling-Ongrowing fish farms-Monitoring) was developed to control the impact of organic waste from marine fish farms in Norway, but it is based on a general concept of environmental management and may be adapted to other fish species and longline shellfish or seaweed farming by adjusting parameters and techniques. 10 sampling station were set and a total of 66 sediment samples were collected. Seasonal variations in three groups of parameters were compared, but no significant differences were detected between the different culture species sites. Benthic animals were found in all samples, and the redox potential stayed above +50 mV. The sediment conditions according to the Groups 2 and 3 parameters of the MOM-system were compared. The results suggest that the Sungou Bay benthic environment belong to condition 1 or 2, which means that the effects of long term shellfish and seaweed farming activities on the benthic environment of Sungou Bay were low. But the result also showed that the impacts in summer and autumn are likely to be greater than in winter and spring. More studies need to be performed to adjust the investigation to Chinese conditions and to shellfish farming, so as to form an adequate system for China. The reasons that keep the Sungo Bay benthic environment in good condition were analysed.