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Toxin-allelopathy among phytoplankton species prevents competitive exclusion

Shovonlal Roy·Joydev Chattopadhyay
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Abstract

Toxic or allelopathic compounds liberated by toxin-producing phytoplankton (TPP) acts as a strong mediator in plankton dynamics. On an analysis of a set of phytoplankton biomass-data that have been collected by our group in the North-West part of the Bay of Bengal, and by analysis of a three-component mathematical model under a constant as well as a stochastic environment, we explore the role of toxin-allelopathy in determining the dynamic behaviour of the competing-phytoplankton species. The overall results, based on analytical and numerical wings, demonstrate that toxin-allelopathy due to the toxin-producing phytoplankton (TPP) promotes a stable coexistence of those competitive phytoplankton that would otherwise exhibit competitive exclusion of the weak species. Our study suggests that TPP might be a potential candidate for maintaining the coexistence and diversity of competing phytoplankton species.

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Shovonlal Roy, Joydev Chattopadhyay. 2006-07-12. Toxin-allelopathy among phytoplankton species prevents competitive exclusion. https://arxiv.org/abs/q-bio/0607016

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