基于定性网络模型评价生态调控情景对海洋牧场生态系统的影响——以獐子岛海洋牧场为例

Evaluating the impact of ecological regulation scenarios in marine ranching ecosystems based on a qualitative network model(QNM):a case study of Zhangzi Island marine ranching

在海洋牧场建设过程中,生态调控方式实施后对海洋牧场生态系统的影响通常难以预测,这对海洋牧场的生态安全和高质量发展提出了严峻挑战。为此,建立了一种基于定性网络模型(Qualitative network model,QNM)的海洋牧场生态系统模拟评价方法,并以獐子岛海洋牧场近岸增殖海域作为研究区域,构建以增殖目标种为核心的定性网络模型,模拟评估海洋牧场3种不同类型的生态调控情景(增殖目标种、移除捕食者、海藻场修复)及其复合条件下,牧场群落范围内的响应,分析海洋牧场生态调控策略与生物功能群变化之间潜在关系。结果显示:目标种增殖(仿刺参和虾夷扇贝)产生的上行效应导致其捕食者呈现积极响应,产生的下行效应导致其它底栖动物、浮游植物和有机碎屑等功能群呈现消极响应,移除捕食者海星产生的下行效应导致虾夷扇贝呈现积极响应,表明在增殖区清除敌害生物的重要性,海藻场修复对整个群落有明显的积极影响,体现了海藻场在养护近岸生态系统的重要生态意义。研究表明:QNM可有效识别生态系统潜在的营养级联效应,评估生物功能群的响应,基于QNM的海洋牧场生态调控模拟评价方法,突破了定量食物网模型在数据有限系统中使用的局限性,可为海洋牧场建设的生态调控策略制定提供科学参考。

During the construction of marine ranches,it is often difficult to predict the impact of the implementation of ecological regulation methods on marine ranch ecosystems,which poses severe challenges to the ecological security and health and high-quality development of marine ranches.In this study,a simulation and evaluation method on the ecosystem of marine ranches based on qualitative network model(QNM) was established,and a qualitative network model centered on the stocked target species was constructed by taking the coastal enhancement waters in the Zhangzi Island marine ranching as the modelled area,including community responses under three types of ecological regulation scenarios(stock enhancement,predator removal,and seaweed bed restoration) and their compounded scenarios in marine ranching,to analyze the potential relationship between ecological regulation strategies and changes in biological function groups.Results showed that the bottom-up trophic cascade effects of stocking the scallop Mizuhopecten yessoensis produced a positive impact on its predators,while the top-down effects had a negative impact on its prey,including other zoobenthos,phytoplankton,and organic detritus.The removal of predatory starfish showed a positive impact on the scallop M.yessoensis through the top-down effects,indicating the importance of removing the enemy organisms in the stocking areas.The simulated strategies of seaweed bed restoration showed a significantly positive effect on the entire community,reflecting the benefits of maintaining or increasing species diversity by seaweed bed in the ecosystem.By overcoming the data dependence of quantitative models,QNM can identify the potential trophic cascade effects and assess the response of biologically functional groups,thus effectively screen the ecological regulation strategies of marine ranches that can achieve the desired management objectives.The simulation and evaluation method of marine ranch ecological regulation based on QNM established in this study,can break through the limitations of using quantitative food web models in systems with limited data,providing the scientific support for the formulation of ecological regulation strategies for marine ranch construction.