What role do wetlands generally play in an ecosystem?

Wetlands play a crucial role in ecosystems, primarily through their function in filtering pollutants. They act as natural water filters, capturing and breaking down contaminants such as sediments, nutrients, and pollutants from water before it moves to other bodies of water. This filtration process improves water quality and helps maintain a healthy aquatic ecosystem.

Furthermore, wetlands provide habitat for a diverse range of species, supporting greater biodiversity and contributing to various ecological processes, such as nutrient cycling and flood control. They also play a significant role in groundwater recharge and can store excess water during periods of heavy rain, helping to mitigate flooding.

In contrast to this function, the other options do not accurately represent the valuable contributions of wetlands to ecosystems. Wetlands are essential for maintaining ecological balance, supporting wildlife, and enhancing water quality, making their role much broader than just filtering pollutants.