Final answer:
Air pollution is the most significant anthropogenic disturbance in national parks, leading to biodiversity loss due to its various harmful effects on ecosystems.
Step-by-step explanation:
The most abundant type of pollution in national parks that can lead to a reduction in biodiversity is air pollution. Air Pollution includes harmful substances released into the atmosphere, which can have devastating effects on various ecosystems and is a significant anthropogenic, or human-related, disturbance. These contaminants can alter environments and contribute to biodiversity loss by impacting plant and animal species in numerous ways, such as changing their habitats, interfering with the reproductive processes of species like the peregrine falcon, and affecting overall ecosystem health.