渤海赤潮藻类生态动力学模型的非线性动力学研究

Nonlinear Dynamics Research of the Algal Model in Bohai Sea

基于渤海典型赤潮藻类——中肋骨条藻 ,考虑浮游动物的捕食、光照及营养物质的作用 ,建立了渤海湾的浮游动物—藻类—营养物质三者的动力学模型。运用现代非线性动力学理论着重分析了模型的稳定性及分岔行为。研究了多个参数对藻类生长的影响 ,发现某些参数对藻类的生长影响不大 ,而某些参数则会致使藻类模型出现分岔乃至混沌行为 ,并给出了这些参数的阀值 ,这与赤潮的形成 (爆发性增殖 )密切相关 ;并根据渤海湾的赤潮数据进行了有效的数值模拟 。

In this paper we studied Skeletonema costatum-the representative algae in the red tide of the Bohai Sea Using the biochemical mechanism of the biology growth and considering the effect of the variation of concentration of nitrogen and phosphor on the algae growth and the light, we got a new growth nonlinear dynamics model of the algae Using the methods of the modern nonlinear dynamics, we discussed the stability of the steady state first, and then focused on the Hopf bifurcation behaviors of the parse solution of the model equation We pointed out that by changing the initial nutrient concentration the model would display complex dynamics behaviors including bifurcation and chaos