近岸海域赤潮藻非线性生态模型的建立和动力学分析

Nonlinear Ecological Model Structuring and Dynamic Analysis on Red Tide Algae in Offshore Area

基于海洋浮游生态系统特性,以主要赤潮藻-中肋骨条藻为研究对象,建立了中肋骨条藻生物量随氮磷营养盐浓度变化的微分方程,并考虑了养料循环和时滞的影响,利用非线性动力学方法得到了边界平衡点的全局渐近稳定性,正平衡点的局部稳定性和Hopf分支的存在性,以及系统持久的充分条件.

In this paper,according to the character of marine planktonic ecosystem and using the main red tide algae—skeletonema costatum as research object,the differential equation of the diatom biomass change with nitrogen and phosphorus nutrient concentration is established.Considering the nutrient cycle and delay effect,using the nonlinear dynamic methods,it can obtain that the global asymptotical stability of boundary equilibrium,the local asymptotical stability of the positive equiUbrium,the existence of Hopf bifurcation and the sufficient conditions of persistence of system.