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
