Calculating the carrying capacity of bivalve mariculture in the Changshan Archipelago (Bohai Strait, China): Ecopath modeling perspective
Xueping Zhang, Hongjun Song, Hongfei Zhuang, Shijie Yi, Xuguang Hong, Jiansong Chu, Zhaohui Zhang
Abstract
Aquaculture has an important role in ensuring human food security and boosting global economic development. Sustainable aquaculture has been confronted with the challenge of balancing economic growth and environmental protection. As an essential part of aquaculture planning, the assessment of carrying capacity based on ecosystem models can be used to significantly guide sustainable management. The Ecopath approach was selected to construct a food web model of the Changshan Archipelago ecosystem, an ecologically important region with long-standing mariculture activities in China. The carrying capacity of bivalve mariculture was also calculated from the model. The results demonstrated that the current bivalve mariculture biomass (45.80 t·km−2) is below the production carrying capacity (72.65 t·km−2) but it is greatly above the ecological carrying capacity (21.06 t·km−2). We also discovered that the ecotrophic efficiency of phytoplankton is close to 1 in the model, which shows that the local primary productivity has been efficiently utilized. Based on ecological network analysis, the values of the energy and cycle index indicate that the Changshan Archipelago is in a mature and stable stage, and a low value of the connectance index indicates a relatively simple ecosystem food web. These findings substantially contribute to our understanding of the Changshan Archipelago ecosystem structure and pave the way for effective management on the coastal archipelago.