What is a characteristic of swamps?

A swamp is a specific type of wetland that is characterized by the presence of rich, nutrient-filled environments often dominated by woody plants. The high concentration of trees and shrubs is a defining feature of swamps, making them distinct from other wetland types like marshes, which are dominated by herbaceous (non-woody) plants.

Swamps typically have water-saturated soil, which supports the growth of various tree species like willows, cypress, and others that thrive in these conditions. This lush vegetation not only plays a significant role in providing habitat for numerous species of wildlife but also helps in water filtration, flood control, and maintaining the health of riparian ecosystems.

The other options present characteristics that do not accurately describe swamps. Herbaceous plant dominance is typical of marshes, and being primarily water-free is a contradiction to the very nature of swamps, which require a certain level of water saturation. Additionally, swamps can be found in various geographical regions, including low-lying areas and floodplains, not exclusively in mountainous regions.