Sarkar Ram Rup, Malchow Horst
Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad 500 007, India.
J Biosci. 2005 Dec;30(5):749-60. doi: 10.1007/BF02703573.
A phytoplankton-zooplankton prey-predator model has been investigated for temporal, spatial and spatio-temporal dissipative pattern formation in a deterministic and noisy environment, respectively. The overall carrying capacity for the phytoplankton population depends on the nutrient level. The role of nutrient concentrations and toxin producing phytoplankton for controlling the algal blooms has been discussed. The local analysis yields a number of stationary and/or oscillatory regimes and their combinations. Correspondingly interesting is the spatio-temporal behaviour, modelled by stochastic reaction-diffusion equations. The present study also reveals the fact that the rate of toxin production by toxin producing phytoplankton (TPP) plays an important role for controlling oscillations in the plankton system. We also observe that different mortality functions of zooplankton due to TPP have significant influence in controlling oscillations, coexistence, survival or extinction of the zoo-plankton population. External noise can enhance the survival and spread of zooplankton that would go extinct in the deterministic system due to a high rate of toxin production.
分别在确定性和噪声环境中研究了一种浮游植物 - 浮游动物捕食 - 被捕食模型，以探讨时间、空间和时空耗散模式的形成。浮游植物种群的总体承载能力取决于营养水平。讨论了营养浓度和产毒素浮游植物在控制藻华方面的作用。局部分析得出了一些稳态和/或振荡状态及其组合。由随机反应扩散方程建模的时空行为同样有趣。本研究还揭示了产毒素浮游植物（TPP）的毒素产生速率在控制浮游生物系统振荡中起重要作用这一事实。我们还观察到，由于TPP导致的浮游动物不同死亡率函数对控制浮游动物种群的振荡、共存、生存或灭绝具有重大影响。外部噪声可以提高浮游动物的生存和扩散能力，而这些浮游动物在确定性系统中会因高毒素产生率而灭绝。
