Both abiotic and biotic factors control phytoplankton dynamics. Among the multiple factors regulating the variability of phytoplankton production and biomass, physical transport that distributes both phytoplankton and other substances (e.g., nutrients, salts, and suspended solids) is one of the key factors in coastal aquatic systems. While the effect of transport processes is best understood by the relationship between phytoplankton biomass/production and transport time (e.g., flushing time, residence time, and age), diverse relationships have been broadly observed. No consensus on the existence of a general relationship has been reached. Using a simplified zero-dimensional mathematical model, we show that diverse relationships between phytoplankton biomass/production and transport time under different conditions of light and nutrient limitations can be synthesized into four patterns in river-dominated coastal aquatic systems. Three patterns show a non-monotonic relationship and one pattern shows a positive relationship. The non-monotonic relationship between biomass and flushing time is demonstrated well by two realistic examples. The revealed non-monotonic relationship provides insight into the widely observed nonlinear responses of many biogeochemical processes to changes in transport processes.

中文翻译：

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以河流为主的沿海水生系统中浮游植物生物量与运输时间之间的典型关系

非生物和生物因素都控制着浮游植物的动态。在调节浮游植物产量和生物量可变性的多种因素中，分配浮游植物和其他物质（例如，养分、盐分和悬浮固体）的物理运输是沿海水生系统的关键因素之一。虽然通过浮游植物生物量/产量和运输时间（例如，冲洗时间、停留时间和年龄）之间的关系可以最好地理解运输过程的影响，但已经广泛地观察到了不同的关系。尚未就普遍关系的存在达成共识。使用简化的零维数学模型，我们表明，在以河流为主的沿海水生系统中，在不同光照和营养限制条件下，浮游植物生物量/产量与运输时间之间的不同关系可以合成为四种模式。三种模式显示非单调关系，一种模式显示正相关。两个实际例子很好地证明了生物量和冲洗时间之间的非单调关系。揭示的非单调关系提供了对许多生物地球化学过程对运输过程变化的广泛观察的非线性响应的洞察。两个实际例子很好地证明了生物量和冲洗时间之间的非单调关系。揭示的非单调关系提供了对许多生物地球化学过程对运输过程变化的广泛观察的非线性响应的洞察。两个实际例子很好地证明了生物量和冲洗时间之间的非单调关系。揭示的非单调关系提供了对许多生物地球化学过程对运输过程变化的广泛观察的非线性响应的洞察。