What are Wetlands?

• Areas where water meets the land
• Has a mixture of  aquatic and wildlife
• Have at least periodically water-logged soil
• Plant life that requires lots of water

WetlandsOverview
The EPA defines a wetland as a area where water covers the soil or where water is at or near the surface of the soil all year round.  There are four major types of wetlands:

Marshes:
Marshes are wetlands that are frequently inundated with water and are characterized by soft stemmed vegetation, plentiful nutrients and neutral pH.  Consequently, animal and plant life is abundant.  Marshes receive surface water and are sometimes fed by groundwater.
Importance of Marshes: Marshes provide water to streams, which recharges groundwater supplies and moderates streamflow.  Marshes in a watershed can reduce flood damage by slowing and storing flood water.  Marshes are also vital in the cleaning of polluted waters.
Swamps:
Swamps are wetlands dominated by woody plants, characterized by saturated soil during the growing season and standing water during other times of the year.  Growth of trees and shrubs happens due to the highly organic soil.  One important species that resides in swamps is the endangered American crocodile.
Importance of Swamps:  Swamps aid in flood protection and nutrient removal.  Lowland swamps provide food that upland creatures eat, and timber found in swamps can be harvested to use as building materials.
Bogs:
Bogs are wetlands that receive most of their water from precipation, and are characterized by acidic waters and moss-covered floors.  Plants and animals in bogs posess special adapatations for the low nutrient levels and acidic waters.  Carnivorous plants can be found in bogs.
Importance of Bogs:  Bogs help prevent downstream flooding by absorbing precipitation.
Fens:
Fens are peat-forming wetlands that receive nutrients from upslope sources like drainage from mineral soils or groundwater movement.  Fens are characterized by low temperatures and short growing seasons.  They support a fairly diverse plant and animal community, and are often covered by grasses, sedges, or wildflowers.
Importance of Fens:  Fens share many functions with bogs.  They aid in flood prevention, and also provide habitat for unique plant and animal species.
 

Benefits of Wetlands

Floods and Runoff

• Wetlands act as sponges, storing snow melt and rainfall and releasing it gradually, this slows flood waters and reduces flood damage

• Filters out organic waste, heavy metals and other pollutants

• Most biologically productive and diverse ecosystems in the world

• Wetlands are the link between our surface water and underground drinking water supplies
• Surface waters and wetlands feed downward to recharge groundwater aquifers

• Coastal wetlands prevent erosion by functioning as a buffer between ocean waves and the land

Toxic Waste Devastates Marshlands in Southern Spain
 

• April 25, 1998 in the southwest region of Spain called Andalucia
• A Dike wall gave way at a reservoir owned by a mining company used for dumping poisonous chemicals
• Five million cubic meters of acidic waste water dumped into Europe's biggest national park in the surrounding area
• Wave moved downstream in the rivers and man made canals to the Gulf of Cadiz
• Nothing could survive this because of the high acidity of the waste
• Waste contained lead, copper, zinc, cadmium, and other metals
• Spillage creates a grave threat to the Coto de Do--ana, which is home to 1/4 million nesting birds
• Coto de Do--ana covers 185,000 acres of warm marshy swamp that provides a home for 250 species of birds
• Long-term threats to the food chain affect not only water birds, but also flora, amphibians and reptiles
• It's also likely that the heavy metals in the waste will eventually make their way into food chains

Toxic Waste Site

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References Used:  U.S. EPA Web Site: www.epa.gov