Niche differentiation in the light spectrum promotes coexistence of phytoplankton species: a spatial modelling approach

TL;DR

This paper uses a spatial reaction-diffusion-advection model to investigate how niche differentiation in the light spectrum can enable coexistence among phytoplankton species, addressing the paradox of the plankton.

Contribution

It introduces a novel model considering the light spectrum as a continuum resource, providing insights into conditions promoting phytoplankton coexistence.

Findings

Niche differentiation in light spectrum promotes coexistence.

Water turbidity influences phytoplankton diversity.

Model predicts coexistence under specific light and turbidity conditions.

Abstract

The paradox of the plankton highlights the apparent contradiction between Gause's law of competitive exclusion and the observed diversity of phytoplankton. It is well known that phytoplankton dynamics depend heavily on two main resources: light and nutrients. Here we treat light as a continuum of resources rather than a single resource by considering the visible light spectrum. We propose a spatially explicit reaction-diffusion-advection model to explore under what circumstance coexistence is possible from mathematical and biological perspectives. Furthermore, we provide biological context as to when coexistence is expected based on the degree of niche differentiation within the light spectrum and overall turbidity of the water.