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TYPES OF WETLANDS.ppt Powered By Docstoc

             VERNAL POOLS

Bogs are one of North America's most distinctive kinds of
  wetlands. They are characterized by spongy peat deposits,
  acidic waters, and a floor covered by a thick carpet of
  sphagnum moss. Bogs receive all or most of their water
  from precipitation rather than from runoff, groundwater or
  streams. As a result, bogs are low in the nutrients needed
  for plant growth, a condition that is enhanced by acid
  forming peat mosses.
Bogs serve an important ecological function
 in preventing downstream flooding by
 absorbing precipitation. Bogs support some
 of the most interesting plants in the United
 States (like the carnivorous sundew), and
 provide habitat to animals threatened by
 human encroachment.                   carnivorous sundew

                The northern pitcher plant
                (Sarracenia purpurea) overcomes
                the nutrient deficiencies of bog life
                by capturing insects in pools of
                water in its leaves and digesting
                them with the help of some local
• Bogs in the United States are mostly found in the glaciated
  northeast and Great Lakes regions (northern bogs), but also
  in the southeast (pocosins). Their acreage declined
  historically, as they were drained to be used as cropland,
  and mined for their peat which was used as a fuel and a
  soil conditioner. Recently, bogs have been recognized for
  their role in regulating the global climate by storing large
  amounts of carbon in peat deposits. Bogs are unique
  communities that can be destroyed in a matter of days, but
  require hundreds, if not thousands, of years to form
   The term "pocosin" comes from the Algonquin
   phrase "swamp on a hill". As its name suggests,
   these swamps are usually located in upland areas.
   They can be found from Virginia, to Northern
   Florida and are particularly abundant in North
   Carolina where they were estimated to cover
   approximately 2,300 square miles in 1979
   (Mitsch and Gosselink, 1984).
• Current
• Herbaceous
• Mild
• No floating
Tidal marshes can be found along
    protected coastlines in middle
    and high latitudes worldwide.
Tidal marshes serve many
    important functions. They
    buffer stormy seas, slow
    shoreline erosion, and are able
    to absorb excess nutrients
    before they reach the oceans
    and estuaries. High
    concentrations of nutrients can
    cause oxygen levels low
    enough to harm wildlife, such
    as the "Dead Zone" in the Gulf
    of Mexico. Tidal marshes also
    provide vital food and habitat
    for clams, crabs, and juvenile
    fish, as well as offering shelter
    and nesting sites for several
    species of migratory waterfowl.
•   Non-tidal marshes are the most
    prevalent and widely distributed
    wetlands in North America.
•   It is easy to recognize a non-tidal
    marsh by its characteristic soils,
    vegetation, and wildlife. Highly
    organic, mineral rich soils of sand,
    silt, and clay underlie these
    wetlands, while lily pads, cattails
    (see photo), reeds, and bulrushes
    provide excellent habitat for
    waterfowl and other small
    mammals, such as red-winged
    blackbirds, great blue herons,
    otters, and muskrats.
                       Swamps are forested
                       wetlands. Like marshes, they
                       are often found near rivers
•   Current            or lakes and have mineral
                       soil that drains very slowly.
•   Woody plants       Unlike marshes, they have
•   More acid/base     trees and bushes. They may
•   No floating soil
                       have water in them for the
                       whole year or for only part
                       of the year. Swamps vary in
                       size and type. Some swamps
                       have soil that is nutrient rich,
                       other swamps have nutrient
                       poor soil. Swamps are often
                       classified by the types of
                       trees that grow in them.
     Types of Swamps
• Conifer Swamps
  – Trees like white cedar, northern white cedar, eastern hemlock, eastern white pine,
    pitch pine, loblolly pine and black spruce are common in conifer swamps.

• Hardwood Swamps
  – Hardwood swamps have trees like red maple, black willow, aspen, cottonwood,
    ashes, elms, swamp white oak, pin oak, tupelo and birches.

• Shrub Swamps
  – Shrub swamps have small trees and bushes like buttonwood, willow, alders and

• Cypress Swamps
  – Cypress swamps are found in the southern United States. They are named for the
    bald cypress tree.
Conifer Swamps       Hardwood Swamps
                     Cypress Swamps
Shrub Swamps     p
   Prairie Pothole
• A prairie pothole is a small wetland that can be found in
  the grasslands of central North America. These areas
  were formed from glacial activity that carved out a large
  number of potholes. Snowmelt and rain fill the potholes
  in the spring and many species of plants such as cattail
  and bulrushes begin to grow. Mallards, pintails and
  gadwalls as well as many other species of ducks nest in
  the pothole marshes.
                                 The prairie potholes of
                                 Canada, Minnesota and
                                 North and South Dakota
                                 were formed by glaciers
                                 scraping over the landscape
                                 during the Pleistocene.
    Vernal pools
• Vernal pools are seasonal depressional wetlands that occur under the
  Mediterranean climate conditions of the West Coast. They are covered by
  shallow water for variable periods from winter to spring, but may be
  completely dry for most of the summer and fall. These wetlands range in
  size from small puddles to shallow lakes and are usually found in a gently
  sloping plain of grassland.
• A slough ("sloo") is a shallow      SLOUGH
  depression or low spot on the
  floodplains that contains
  slowly moving water. Many
  animals depend upon these
  areas for food and water
  during dry periods. A slough
  can be found in the
  southeastern United States.
  Plants and trees that could be
  found in a slough include
  pickerelweed, alder, willow
  and bulrushes. Creatures found
  in the water and nearby
  include snails, stickleback fish,
  tiger salamanders, bitterns and
• A fen is a type of wetland fed
  by alkaline, mineral-rich
  groundwater and characterized
  by a distinctive flora. Fens are
  often confused with bogs,
  which are fed primarily by
  rainwater and often inhabited
  by sphagnum moss, making
  them acidic. Like other
  wetlands, fens will ultimately
  fill in and become a terrestrial   Fens, like bogs, are
  community such as a woodland       peatlands, but because
                                     they are fed by
  through the process of
                                     groundwater they are
  ecological succession.
                                     not so acidic as bogs.

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