The sharp decline in an aquatic ecosystem could be attributed to what factor?

Thermal pollution is a significant factor that can lead to a sharp decline in aquatic ecosystems. This occurs when industries or power plants discharge heated water into nearby water bodies, raising the temperature of the water. Elevated temperatures can disrupt the delicate balance of aquatic environments by affecting the solubility of oxygen—warmer water holds less oxygen, which is critical for the survival of fish and other aquatic organisms. This can lead to a decline in biodiversity, as sensitive species may not survive the increased temperatures, prompting changes in the community structure and possibly leading to the collapse of local ecosystems.

Additionally, thermal pollution can also encourage the proliferation of harmful algae blooms, which further deplete oxygen levels and can release toxins harmful to aquatic life. These effects create a series of negative consequences that can dramatically alter the health and functionality of aquatic ecosystems.

In contrast, overfishing can lead to resource depletion but may not affect the ecosystem as immediately as thermal pollution. Increased rainfall can impact water quality and sedimentation, while the introduction of invasive species poses long-term ecological risks, but thermal pollution has immediate and severe effects that can lead to a quick decline in ecosystem health.