What are wetlands and why are they important?

13 February 1998

Wetlands are the link between water and land. They are areas that, whether or not they are covered by surface water, have water-logged soil at least periodically. The amount of water present and the timing of its presence determine the functions of a wetland and its role in the environment. They are among the most biologically productive and diverse ecosystems in the world, supporting the growth of water-loving plants and providing homes to thousands of fish and wildlife communities.

The American Alligator is one of many endangered species that depend on wetlands for survival. In North Carolina, alligators reside primarily in the rivers and wetlands in the southeastern region of the state, but can also be found as far north as the Albemarle Sound.

The American Alligator is one of many endangered species that depend on wetlands for survival. In North Carolina, alligators reside primarily in the rivers and wetlands in the southeastern region of the state, but can also be found as far north as the Albemarle Sound.

Scientists recognize five major wetland systems: marine, estuarine, lacustrine, riverine and palustrine. Marine and estuarine systems include coastal habitats such as bays and sounds, the coastline, salt marshes and coastal brackish waters. The other three systems represent inland freshwater habitats, which account for 90 percent of the nation’s wetlands. Lacustrine systems are found along the low-lying areas and margins surrounding lakes, reservoirs and ponds. Riverine wetlands are comprised of floodplains along freshwater rivers and streams. Palustrine wetlands include marshes, bogs and swamps.

Ranging from the small prairie potholes of the northern plain states to the vast swamplands of the Florida Everglades, wetlands occur in every region and climate of the United States. North Carolina has more than 5 1/2 million acres of wetlands; 95 percent are located in the coastal plain. Several kinds of wetlands can be found in the state – lush bottomland; hardwood forests that grow in the floodplains of our rivers and streams; densely vegetated pocosins (from the Indian word for “swamps on a hill”) found nowhere else in the world except North and South Carolina; Carolina bays, unique, egg-shaped depressions found mostly in the southeastern portion of the state; and rich, fertile salt marshes of the coast, where the land meets the sea.

Wetlands play many important roles in protecting our health, safety, property and economy. They aid in flood control, acting as sponges to absorb excess rainfall and snowmelt and then releasing them slowly. They improve our water quality by filtering out organic wastes and other pollutants. Coastal wetlands prevent erosion and property damage by functioning as natural buffers against damaging storm waves. And, they are critical to the success of the commercial fishing industry, serving as safe spawning grounds and nurseries for fish and shellfish.

Wetlands are also vital to thousands of plant and animal species that depend on this rich habitat for survival. These “biological supermarkets” provide great volumes of food that attract and sustain many animal species. Many other animals, such as migratory waterfowl, use wetlands for breeding grounds, resting sites and shelter from weather and predators. Although wetlands occupy less than 5 percent of the land in the lower 48 states, more than one-third of all federally listed threatened and endangered species live only in wetlands, and nearly half use wetlands at some point in their life.

In the past 200 years, more than half the wetlands in the lower 48 states have been drained, paved, filled or destroyed. Wetlands loss has slowed over recent years, thanks to federal and state protective regulations and efforts by conservation and environmental groups. However, continued efforts are vital to ensure the protection and preservation of these fragile cradles of life.