1/21/2014. Definitions vary widely Legal vs. functional Not always obvious. Wetlands are legally protected by Clean Water Act (1972)

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1 What is a Wetland? Freshwater Wetlands of Gulf Coast Plains Definitions vary widely Legal vs. functional Not always obvious What is a Wetland? Wetlands are legally protected by Clean Water Act (1972) Corps of Engineers definition: "those areas that are inundated or saturated by surface or groundwater at a frequency and duration sufficient to support, and that under normal circumstances do support, a prevalence of vegetation typically adapted for life in saturated soil conditions." What is a Wetland? Must have water (surface or root zone) Unique soils Hydrophytic vegetation Adapted from Mitsch and Gosselink, 2007 What is a NOT a Wetland? Types of Wetlands Navigable waters Standing or flowing waters that form geographic features (e.g., ocean, creek, lake, river, etc.) EPA categories: Marshes Swamps Bogs Fens Mitsch & Gosselink categories Tidal Salt Marshes Tidal Mangrove Swamps Inland Peatlands Freshwater Swamps Riparian Ecosystems americaslongleaf.org 1

2 Pulsed River Systems Flood Pulse Concept: Riverine flooding is the main driver for many wetland ecosystems Especially true for low elevation floodplains Sea level (long term) and coastal (short term) flooding are also important Boundaries shift based on precipitation and sea level Diversity moderately high Productivity high Hydrology non-tidal, Riverine flooding Groundwater and/or Precipitation Common species Cordgrass Duck potato Pickerelweed Needle rush Wild rice Alluvial Flood Plain Google Earth,

3 Meander Scars (Oxbows) Riverine swamp Formed by channel redirection from flooding Vary in hydrology Eventually fill in with sediments Meander Scars (Oxbows) Diversity moderate to low Productivity moderate Hydrology non-tidal, Riverine flooding Precipitation Google Earth, 2014 Meander Scars (Oxbows) Common species Pond cypress Water tupelo Bottomland Hardwoods Riverine swamp Experience frequent flooding Have hydrophytic vegetation Do not always have hydric soils (thus not always a legal wetland) Bottomland Hardwood Diversity moderate to low Productivity moderate Hydrology non-tidal, Riverine flooding Precipitation Bottomland Hardwood Common species Sweetbay Virginia sweetspire Winterberry Dwarf palmetto Hackberry 3

4 Bottomland Hardwoods Braided Stream Systems Not an official type of wetland Sometimes link other wetland types (oxbows, bottomland hardwoods, etc.) Braided Stream Systems Braided Stream Systems Not an official type of wetland Common species: Swamp titi Southern bayberry Sphagnum Winterberry Virginia sweetspire Fetterbush Sweetbay Cypress Strands Cypress Strands Flatland swamp Forms linear channel Strands not always connected Common species: Pond cypress 4

5 Citronelle Ponds Citronelle Ponds Common species: Myrtle dahoon Water lily Laurel greenbrier Bogs Fens Acidic wetlands with deep peat deposits characterized by large amounts of Sphagnum Unfortunately, none of our bogs fitneatlyintothis into this category. Similar to bogs but are dominated by grasses and sedges. Variable phs Acidic fens are often called poor fens Carnivorous plants are characteristic of poor fens Coastal plain pitcher plant bogs are technically poor fens Pitcher Plant Bogs Pitcher Plant Bogs Acidic, seepage fens Fire dependent Common Species Pitcher plants Sundews Yellow-eyed grass 5

6 Upland Ephemeral Ponds Carolina Bays Shallow upland depressions Perched water table Ecosystem Services Management Issues Primary productivity Water filtration/purification Groundwater replenishment Flood control Shoreline stabilization Recreation Mitigation Development Draining Dredging Revegetation Saltwater Intrusion Suggested Reading T.E. Dahl and S.M. Stedman Status and trends of wetlands in the coastal watersheds of the Conterminous United States 2004 to U.S. Department of the Interior, Fish and Wildlife Service and National Oceanic and Atmospheric Administration, National Marine Fisheries Service. (46 p.) W.J. Mitsch and J.G. Gosselink Wetlands, 4 th edition. Wiley & Sons, N.J., U.S.A. 6