In aquatic microbial systems, high-magnitude variations in abundance, such as sudden blooms alternating with comparatively long periods of very low abundance (“apparent disappearance”), are relatively common. We suggest that in order for this to occur, such variations in abundance in microbial systems and, in particular, the apparent disappearance of species do not require seasonal or periodic forcing of any kind or external factors of any other nature. Instead, such variations can be caused by internal factors and, in particular, by bacteria–phage interaction. Specifically, we suggest that the variations in abundance and the apparent disappearance phenomenon can be a result of phage infection and the lysis of infected bacteria. To illustrate this idea, we consider a reasonably simple mathematical model of bacteria–phage interaction based on the model suggested by Beretta and Kuang, which assumes neither periodic forcing nor action of other external factors. The model admits a loss of stability via Andronov–Hopf bifurcation and exhibits dynamics which explains the phenomenon. These properties of the model are especially distinctive for spatially nonhomogeneous biosystems as well as biosystems with some sort of cooperation or community effects.

中文翻译：

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海洋噬菌体动力学中的富集、空间异质性、群落效应和明显消失现象的悖论

在水生微生物系统中，丰度的大幅度变化，例如突然开花与相对较长时间的非常低丰度（“明显消失”）交替出现，是相对常见的。我们建议，为了发生这种情况，微生物系统中丰度的这种变化，特别是物种的明显消失，不需要任何类型的季节性或周期性强迫或任何其他性质的外部因素。相反，这种变化可能是由内部因素引起的，特别是由细菌-噬菌体相互作用引起的。具体来说，我们认为丰度的变化和明显的消失现象可能是噬菌体感染和受感染细菌裂解的结果。为了说明这个想法，我们基于 Beretta 和 Kuang 提出的模型考虑了一个相当简单的细菌 - 噬菌体相互作用的数学模型，该模型既不假设周期性强迫，也不假设其他外部因素的作用。该模型承认通过 Andronov-Hopf 分岔失去了稳定性，并展示了解释该现象的动力学。该模型的这些特性对于空间上非同质的生物系统以及具有某种合作或社区效应的生物系统来说尤其独特。