Wetlands: Wetlands What are they? Why are they important?


What are wetlands?: What are wetlands? The U.S. Fish and Wildlife Service defines wetlands as the “…lands transitional between terrestrial and aquatic systems where the water table is usually at or near the land surface or the land is covered by shallow water.” (Cowardin et al., 1979) Wetlands must have all of the following characteristics: Hydric soil Hydrology Hydrophytic vegetation


Types of wetlands in NE Illinois: Types of wetlands in NE Illinois Marsh


Slide5: Forested wetland


Slide6: Wet Meadow


Slide7: Bog and fen


Historical perspective on wetlands: Historical perspective on wetlands The U.S. total of natural wetlands is estimated at 127 million acres By 1950 45 million acres (35%) had already been drained Wetlands covered 40-61% of Lake County before settlement Presently only 10-19% of the area are wetlands (see figures) Most wetlands were lost to agricultural expansion Some were lost to development due to population growth They were considered wastelands and destroyed until recent scientific research and environmental awareness stressed their importance


Extent of wetlands in Lake County: Extent of wetlands in Lake County


Why are they important?: Why are they important? Hydrologic value—refers to the distribution and movement of water on or below the earth’s surface -wetlands are capable of slowing down and retaining water (especially important during floods or heavy rain) -wetlands play an important role in groundwater recharge -plants along bodies of water slow down sediment deposits in streams and lakes (process called erosion) thus improving water quality


Wetland importance…: Wetland importance… Habitat value—wetlands are some of the most biologically rich ecosystems in the world comparable to tropical rainforests and coral reefs -wetlands provide habitats for amphibians, fish, wildlife, birds and plants -some of the species can only survive in the wetland environment -there are 500 species of plants and animals threatened with extinction in Illinois; 55% of these depend on wetlands or other aquatic habitats for survival (spotted turtle, Illinois chorus frog, four-toed salamander, black- crowned night heron and many more)


Wetland importance…: Wetland importance… Direct use value --ecotourism --fishing --production of saw timber and pulpwood --environmental education


Wetland importance…: Wetland importance… Water quality --wetlands remove pollutants from surface runoff and streams --wetland plants reduce algae bloom and fish kills by transforming nitrogen and phosphorus into available forms


Did you know that…?: Did you know that…? Wetlands are often referred to as “the kidneys of the landscape” because they filter out harmful materials One acre of wetland can store 1-1.5 million gallons of floodwater Wetlands comprise only 5% of the contiguous U.S., although they are home to 31% of all plant species As many as 50% of North American bird species either nest or feed in wetlands Lake County ranks 2nd in Illinois for percentage of natural wetlands (10.2%) and 3rd for all wetlands (11.1%)


Pollution Sources and Prevention: Pollution Sources and Prevention Illustration using a watershed model called the Enviroscape


Slide18: Questions?


Slide19: Thank you!!