大连獐子岛海刺参人工养殖主要病虫害防治策略的数学机理研究

The project focused on the phenomenon that a variety of diseases appeared and mass mortality happened in the Dalian sea cucumber breeding process, to deal with the mathematical mechanism of sea cucumber major diseases and predator species Microset tela sp synthetical prevention systematically. Firstly, based on the bacteria infection level of the sea cucumber in marine, we build up the bacteria - sea cucumber epidemic dynamics model by means of statistical methods. Then we analyze the bacteria’s evolution trends and the impact to sea cucumber, and give approximate optimal strategies for disease prevention by using approximate optimization theory. Secondly, in view of the special competitive, predator-prey relationship between sea cucumber and predator species, and sufficiently consider sea cucumber’s features of discoloring, dirty rowing and replication, we initially establish the competition - predation mixed kinetic model between sea cucumber and predator species Microset tela sp. Then we analyze the impact of predator species to sea cucumber by applying the qualitative and stability theory of differential equations, which provides a theoretical basis for the effective prevention and control of sea cucumber’s predator species. The carrying out of the project will not only promote the basic theoretical research in infectious diseases and population dynamics, but also provide a reliable theoretical basis and strong technical support for the sustained, healthy and stable development of sea cucumber aquaculture.

针对于大连獐子岛海刺参人工养殖过程中出现的多种明显病症及大规模死亡现象, 本项目拟从理论上系统研究海刺参养殖主要病虫害防治策略的数学机理问题。首先, 基于海水中细菌对海刺参的感染水平, 借助于统计学方法以及传染病模型来构建细菌-海参流行病动力学模型, 分析细菌的演化趋势以及对海刺参的影响, 并利用近似最优化理论给出疾病预防的近似最优策略。其次, 鉴于海刺参与敌害物种之间存在的竞争关系、捕食关系以及海刺参自身所具备的变色、排脏、分身等特点, 初步建立海刺参与敌害物种猛水蚤之间的竞争-捕食混合动力学模型。并利用常微分方程定性与稳定性理论分析模型的动力学性质, 根据所得结论分析敌害物种对幼年海刺参的影响, 进而为幼年海刺参敌害物种的有效治理提供理论依据。本项目的开展既能促进传染病与种群动力学的基础理论研究, 又能为海刺参养殖业的持续、健康、稳定发展提供可靠的理论依据和强有力的技术支持。

本课题针对大连獐子岛地区海刺参人工养殖过程中出现的细菌性溃烂病及猛水蚤危害这一现实问题，从数学模型方面开展了海刺参主要病虫害防治策略研究。首先，考虑到海刺参养殖过程中易受到水环境及限制性基质中有害病菌等因素影响，通过将物种按其受感染程度划分为易感和已感两类，建立了基于病菌感染的海洋生物恒化培养三维动力学模型，并借助于微分方程定性与稳定性理论对所建立的模型进行了性态分析。其次，考虑到海刺参培养过程溶解氧通常随生物质浓度而变化，为了使培养池内溶解氧浓度不低于培养过程的最低阈值要求，建立了基于状态反馈的海洋生物养殖过程动力学模型，借助于半连续动力系统理论对所建立的模型进行了性态分析，并对溶解氧浓度进行了预测。再次，为了控制猛水蚤的数量，建立了基于状态反馈控制的猛水蚤综合治理模型，并借助于连续和半连续动力系统理论对所建立的模型进行了动力学性态分析和预测。同时，为了减小投入控制成本，对相关控制参数进行了优化处理。本项目的相关研究成果可为海刺参养殖过程病虫害防治提供一定的参考和依据。