A discrete-time nutrients-phytoplankton-oysters mathematical model of a bay ecosystem*

Populations are generally censused daily, weekly, monthly or annually. In this paper, we introduce a discrete-time nutrients-phytoplankton-oysters (NPO) model that describes the interactions of nutrients, phytoplankton and oysters in a bay ecosystem. We compute the threshold parameter [Formula: see...

Full description

Bibliographic Details
Main Author: Najat Ziyadi
Format: Article
Language:English
Published: Taylor & Francis Group 2023-12-01
Series:Journal of Biological Dynamics
Subjects:
Online Access:https://www.tandfonline.com/doi/10.1080/17513758.2023.2242720
Description
Summary:Populations are generally censused daily, weekly, monthly or annually. In this paper, we introduce a discrete-time nutrients-phytoplankton-oysters (NPO) model that describes the interactions of nutrients, phytoplankton and oysters in a bay ecosystem. We compute the threshold parameter [Formula: see text] for persistence of phytoplankton with or without oysters. When [Formula: see text], then both phytoplankton and oysters populations go extinct. However, when [Formula: see text], we show that the model may exhibit two scenarios: (1) a locally asymptotically stable equilibrium with positive values of nutrients and phytoplankton with oysters missing, and (2) a locally asymptotically stable interior equilibrium with positive values of nutrients, phytoplankton and oysters. We use sensitivity analysis to study the impact of human and environmental factors on the model. We use examples to illustrate that some human activities and environmental factors can force the interior equilibrium to undergo a Neimark–Sacker bifurcation which generates phytoplankton blooms with oscillations in oysters population and nutrients level.
ISSN:1751-3758
1751-3766