Is toxicity a curse or blessing, or both?—Searching answer from a disease-induced consumer-resource system

Abstract

Chemical toxins exposed in environments and disease outbreaks are global threats to ecosystems in the present era of the anthropocene. Toxin favors disease progression trivially. However, it is still unclear whether the toxin impacts disease elimination too. Toxin also has a significant role in amplifying the risk of disease-induced consumer extinction. Identification of the extinction vortex and its associated precursors are the two most important pillars for understanding the effect of the toxin on the sustainability of ecosystems. On the other hand, the contribution of toxin as a potential agent for stabilizing a disease-induced consumer-resource system is still unclear. Although disease stabilizes the system in absence of toxicity. In order to address this, we consider a mathematical model of disease transmission in the consumer population where both ecological and epidemiological traits are affected by environmental toxins. The proposed model integrates two compartments (susceptible and infected) for consumers and the resource, where the toxin is incorporated in the form of species body burdens. Apart from the formal stability analysis, we extensively use codim-1 and codim-2 bifurcation through MATCONT software for understanding the different dynamical regimes of disease progression and elimination. These derived regimes will be helpful to raise the alarm and take intervention policies.