EFFECTS OF COMBINED HARVESTING AND ENVIRONMENTAL POLLUTION ON STABLE COEXISTENCE IN TWO-SPECIES COMPETITION SYSTEMS

Abstract

Ecological communities face significant challenges from human-induced pressures such as overharvesting and environmental pollution, threatening the stability and coexistence of two-species systems. This thesis investigates how environmental contamination and harvesting impact the stable coexistence of two competing species using a mathematical modeling approach. Four scenarios are analyzed: (1) the presence of both harvesting and pollution, (2) harvesting only, (3) pollution only, and (4) the absence of both factors. The models incorporate non-selective harvesting activities and pollution-induced declines in intrinsic growth rates and carrying capacities. Comparative analysis reveals that combined harvesting and pollution significantly destabilize the system, making coexistence difficult. Conversely, the absence of both pressures creates the most favorable conditions for stable coexistence. Excessive harvesting efforts and high pollution levels can disrupt coexistence, potentially leading to the extinction of both species. These findings offer a framework for regulating species sustainability under environmental pressures and contribute to a deeper understanding of ecological interactions. Numerical examples are provided to demonstrate the important outcomes in the study