Wetlands 101

What is a wetland?

A wetland is any place where there is shallow water or very soggy soil for part of the year. The soil could be either permanently or seasonally saturated1, and over time it takes on the characteristics of a distinct ecosystem. Because of the presence of water, the wetland will develop wet (“hydric”) soils and will provide habitat for wetland plants, which are adapted to the wetter environment.

Why should we care about wetlands? Why do they matter?

Wetlands are often described as the “kidneys of the landscape” because of the important natural benefits they provide:

  1. Wetlands act like a sponge, holding water for a variety of services across the landscape.
  2. Wetland protect our communities from flooding.
  3. Wetlands play a major role in protecting our shorelines.
  4. Wetlands provide critical fish, wildlife, bird, and amphibian habitat.
  5. Wetlands clean and filter water for drinking, swimming, boating, and fishing.
  6. Wetlands help regulate stream flow and recharge our groundwater.
  7. Wetlands provide beautiful places for education, recreation, and relaxation. In fact, without wetlands, thousands of animals and plants would become extinct, and floods and pollution would be much worse.

Lakes are wet, are they wetlands too?

No – they are too wet. Remember wetland plants? Lakes are mostly too deep for wetland plants to take hold. But, wetlands can develop along the edges of lakes.

Where do wetlands develop?

Wetlands can show up anywhere that water may sit long enough for a saturated soil to develop hydric soil characteristics associated with prolonged saturation and changing wet and dry cycles. Wetlands are often found by rivers, streams, lakes, and oceans, but they can also develop in upland depressions or at the base of a slope.

How do wetlands get wet?

Besides precipitation, wetlands can receive water that seeps from underground, overland runoff, or water that floods from rivers and streams or ocean tides.

What types of wetlands are there in North and South Carolina and how are they different? How are they defined, or how are they characterized?

There are many different types of wetland communities in the Carolinas; in fact, some wetland communities are almost entirely unique to this part of the country, like Carolina bays and pocosins.

Wetland scientists have developed “classification systems” to organize wetlands with similar characteristics. The “Cowardin” and “Hydrogeomorphic” (HGM) classification systems can be used anywhere in the country while the “North Carolina Wetland Assessment Method” (NCWAM) was developed specifically for North Carolina and is also useable in South Carolina and Virginia. “The Guide to Natural Communities of North Carolina” used by the NC Natural Heritage Program (NHP) and “The Natural Communities of South Carolina” are two other more detailed classification systems developed for use in the Carolinas. These multiple wetland classification systems have resulted in different names for the same wetland community. For example, a “Riverine Swamp Forest” identified by NCWAM could also be called a “Gum Swamp” or “Cypress Gum Swamp” by the NC NHP classification system. NCWAM defines just 16 types of wetlands while “The Guide to Natural Communities of North Carolina” and “The Natural Communities of South Carolina” define over 100 types together!

What wetland characteristics are used by the NCWAM classification system?

Hydrology – Does the water source seep from underground, or does it flow overland from rivers, streams, or ocean tides? Is the wetland flooded for most of the year or is the soil saturated for a few months?

Landscape position – Is the wetland near a lake, river, or stream or is it higher up in the watershed and surrounded by upland?

Soil type – Does the wetland have mineral soil like sand or silt, or is the soil organic like the muck or peat found in a bog?

Vegetation structure – Is the wetland forested, shrub covered, or herbaceous?

Dominant vegetation species – What types of trees, shrubs, or herbaceous plants are most prevalent in the wetland community?

Learn more about wetland communities in the Carolinas, what lives there, and where you can go to visit examples of these beautiful places.

 

 

References:

Brinson. M.M. 1993. A hydrogeomorphic classification for wetlands, Technical Report WRP-DE-4, U.S. Army Corps of Engineers Engineer Waterways Experiment Station, Vicksburg, MS.

Cowardin, L. M., V. Carter, F. C. Golet, and E. T. LaRoe. 1979. Classification of Wetlands and Deep Water Habitats of the United States.

Wisconsin Wetlands Association website: wisconsinwetlands.org, 214 N. Hamilton St. #201 Madison, WI 53703.

Mitsch, W.J. and J.G. Gosselink. Wetlands, 2nd Edition. Van Nostrand Reinhold Publishing. 1995. National Wildlife Federation. 2016.

Nelson, John B. The Natural Communities of South Carolina. 1986. South Carolina Wildlife & Marine Resources Department.

North Carolina Wetland Functional Assessment Team. 2010. North Carolina Wetland Assessment Method (NCWAM) Version 4.1.

Schafale, Michael P. Guide to the Natural Communities of N. C., Fourth Approximation. 2012. North Carolina Natural Heritage Program, NC Department of Environment and Natural Resources.

US Environmental Protection Agency. 2016. National Wetland Condition Assessment 2011: A Collaborative Survey of the Nation’s Wetlands.