In homogeneous environments, by overturning the possibility of competitive exclusion among phytoplankton species, and by regulating the dynamics of overall plankton population, toxin-producing phytoplankton (TPP) potentially help in maintaining plankton diversity—a result shown recently. Here, I explore the competitive effects of TPP on phytoplankton and zooplankton species undergoing spatial movements in the subsurface water. The spatial interactions among the species are represented in the form of reaction-diffusion equations. Suitable parametric conditions under which Turing patterns may or may not evolve are investigated. Spatiotemporal distributions of species biomass are simulated using the diffusivity assumptions realistic for natural planktonic systems. The study demonstrates that spatial movements of planktonic systems in the presence of TPP generate and maintain inhomogeneous biomass distribution of competing phytoplankton, as well as grazer zooplankton, thereby ensuring the persistence of multiple species in space and time. The overall results may potentially explain the sustainability of biodiversity and the spatiotemporal emergence of phytoplankton and zooplankton species under the influence of TPP combined with their physical movement in the subsurface water.

中文翻译：

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无毒浮游植物、有毒浮游植物和浮游动物之间的空间相互作用：时空出现

在同质环境中，通过推翻浮游植物物种之间竞争排斥的可能性，并通过调节整体浮游生物种群的动态，产毒浮游植物 (TPP) 可能有助于维持浮游生物多样性——最近显示的结果。在这里，我探讨了 TPP 对在地下水中进行空间运动的浮游植物和浮游动物物种的竞争影响。物种之间的空间相互作用以反应扩散方程的形式表示。研究了图灵模式可能会或可能不会发展的合适参数条件。物种生物量的时空分布使用对自然浮游系统来说现实的扩散率假设进行模拟。该研究表明，在 TPP 存在下，浮游系统的空间运动会产生并维持竞争浮游植物以及食草动物浮游动物的不均匀生物量分布，从而确保多个物种在空间和时间上的持久性。总体结果可能解释了生物多样性的可持续性以及浮游植物和浮游动物物种在 TPP 及其在地下水中的物理运动的影响下的时空出现。