Evaluating the growth potential of a typical bivalve-seaweed integrated mariculture system - a numerical study of Sungo Bay, China

Abstract A biophysical model was used to study bivalve-seaweed integrated culture in Sungo Bay, a typical intensive longline mariculture site in China. Based on this model, the observed variations in pelagic variables and growth of cultivated species were reasonably reproduced. The results showed that the nutrients carried by water exchange were more than sufficient to support the growth of kelp, while the growth of oysters was mainly supported by the local accumulation of phytoplankton, and the majority of scallop's food was supplied by water exchange. A reduction of water exchange would lead to a decrease in the quality of scallops, whereas the growth of oysters would be promoted. Considering the interactions among species and areas, the growth potential of mariculture in Sungo Bay was evaluated. From an area-scale perspective, mariculture in specific areas has certain growth potential. From a bay-scale perspective, the seeding density in the bay should be reduced. In addition, a precise assessment of growth potential should be a tradeoff between seeding density and water exchange. Although further improvement is needed, this model is an effective tool to assist with the management of spatially heterogeneous aquaculture systems, and similar approaches can be applied to other aquaculture sites.