Yellow River Estuary and adjacent waters are famous shellfish production areas. Mactra veseriformis, Ruditapes philippinarum, and Meretix meretrix are important species for stocking enhancement. At present, the annual output of shellfish bottom sowing culture has reached 300 thousand tons, with an output value of 1.54 billion RMB. Over stocking of shellfish will cause environmental changes in marine, increase shellfish mortality and endanger ecosystem health. Accordingly, the assessment of the carrying capacity for shellfish based on ecosystem underpins responsible marine fisheries enhancement. In this study, an Ecopath mass-balance model of the Yellow River estuary and adjacent waters ecosystem constructed by Ecopath with Ecosim software was used to analyze the summary statistics parameters of the ecosystem, mixed trophic interactions, and to calculate the ecological carrying capacity of shellfish. The results showed that the ratio of total primary production/total respiration (TPP/TR) was 3.45, that of total primary production/total biomass (TPP/B) was 38.91, with the low Finn cycling index (0.028), high surplus production being 961.24 t·km-2·a-1 and low system connecting index (0.38), indicating that this ecosystem was at an unstable development stage. The increases of shellfish biomass would have positive impacts on Gobiidae, shrimps, crabs, and negative impacts on pelagic fishes, demersal fishes, edible jellyfish, zooplankton. Current biomass of shellfish was 5.5 t·km-2, with the potential enhancement. Based on the Ecopath model, the primary assessment of carrying capacity of shellfish was 18.22 t·km-2 in Yellow River estuary and its adjacent waters. This study provides scientific references for the sustainable development of fisheries resources in the Yellow River estuary.
黄河口邻近水域是著名的贝类生产区,四角蛤蜊、菲律宾蛤仔、文蛤等是该海域重要的增养殖品种.目前,贝类底播养殖最高年产量达30万t,实现产值15.4亿元.然而,贝类过度增殖,将引起海域环境的变化,继而导致贝类死亡率的增加,影响生态系统的健康.因此,基于生态系统的贝类生态容量评估至关重要.本研究利用Ecopath with Ecosim软件构建了黄河口邻近水域生态系统营养通道模型,在此基础上分析了该生态系统功能群间的相互影响、生态系统的总体状态,并评估了贝类的生态容量.结果表明: 系统的总初级生产量/总呼吸(TPP/TR)为3.45、总初级生产量/总生物量(TPP/B)为38.91,同时具有较低的循环指数(FCI=0.028)、较高的剩余生产量961.24 t·km-2·a-1和较低的系统连接指数(CI=0.38),说明该系统目前处于发育的不稳定期.贝类生物量的增加对虾虎鱼、虾类和蟹类有正影响, 对中上层鱼类、底层鱼类、海蜇、浮游动物等功能群有负影响.当前贝类的生物量是5.5 t·km-2,有一定的增殖潜力.模型估算得出的贝类生态容量是18.22 t·km-2,该研究结果可为黄河口邻近水域渔业资源的可持续发展提供管理依据.
Keywords: Ecopath model; Yellow River estuary; ecological carrying capacity; shellfish.