Disappearing Wetlands

1. DISAPPEARING WETLANDS
Population Pressures and Global Effects
David Severson

2. What is a wetland?
◊Transitional zones between uplands and aquatic habitat
◊Land is submerged in water most of the year
◊Consist of soils that are low in oxygen
◊Habitat for adapted plant and animal species
© D. Severson, 2013

3. Types of Wetlands
►Marshes
►Bogs
►Swamps
►Fens © D. Severson, 2011

4. Why are Wetlands Important?
►Water Purification
►Flood Control
►Shoreline Stabilization
►Wildlife Habitat
►Atmospheric Maintenance
© D. Severson, 2010

5. Wetlands conservation is very important to me. In my youth I
began hunting waterfowl, snipe and woodcock in our
nation’s respective marshes, bogs and swamps. That
tradition carries on to this day. Wetlands are magical places,
full of wonder and abound with life. I became enlightened in
the marsh grass several decades ago and found a serene
place to reflect. I have personally seen the effects of
population growth, urban sprawl and increased agricultural
output on my old duck hunting haunts. Some of these
wetlands have been filled with sand and gravel for housing
tracts while others have become home to industrial facilities.

6. So where have our wetlands gone? More than half of the wetlands in the
contiguous U.S. have been ravaged since the 1600s. California and Iowa
have lost 99% of their wetlands, other states experiencing similar losses
since the 1970s, including Louisiana, Florida and Mississippi (Turner &
Gannon, 2001). The leading causes of degradation are hydrologic
alteration, nonpoint source pollution and questionable agricultural
practices (USEPA, 2001). Perhaps the most devastating aspect is
pollution input from agricultural runoff. The 2000 National Water
Quality Inventory, states that “Agricultural nonpoint source (NPS)
pollution is the second largest source of impairment to wetlands”
(Agricultural Nonpoint Fact Sheet, 2005, p. 1). Fertilizer, herbicide,
pesticide and sediment all impair these resources and have the potential
to contaminate wetlands. © 2014 Utah State University

7. Best Management Practices
Fortunately a host of best management practices (BMPs)
have been developed to minimize wetland loss and
degradation.
Reduction and management of excess nutrients entering
watersheds is paramount. Livestock waste is high in
nitrogen and phosphorus which can lead to eutrophication
of wetlands, eliminating their natural filtering capabilities.
Maintaining riparian zones where land borders water
absorbs excess nutrients, eliminating burden on wetlands.
Soil erosion also plays a large role in the health of
wetlands. By reducing the frequency of plowing and
tilling farm fields, less sediment will enter the wetland,
improving its filtering capacity. Cover crop techniques are
also useful. Some grains and grasses will absorb excess
nitrogen before it reaches the wetland. (USEPA, 2014)

8. Farming to the river’s edge, Non-BMP. © D. Severson, 2012

9. Riparian buffer (BMP) along a tributary of the Chesapeake Bay.
© Longstaff, 2007

10. Typical northern Maine bog and cow moose.
© Severson, 2010

11. © D. Severson, 2010

12. Conclusion
The future of wetlands is uncertain and I find that
unsettling. Wetlands will remain the kidneys of the
Earth whether they are in peril or not. If these fragile
components of the planet cease to function what will
become of planet Earth and its inhabitants?
© D. Severson, 2005

13. References:
Agricultural Nonpoint Source Fact Sheet. (2005). Retrieved from
http://water.epa.gov/polwaste/nps/agriculture_facts.cfm
Turner, M. H., & Gannon, R. (2001). Information on wetlands. Retrieved from
http://www.water.ncsu.edu/watershedss/info/wetlands/:
United States Environmental Protection Agency. (2014). The sources and solutions: Agriculture (). Washington, DC:
Government Printing Office.
Image 1 : Retrieved from: http://upload.wikimedia.org/wikipedia/commons/0/0f/Wetland_Hong_Kong.jpg
Image 8: Longstaff, B. (2007). Riparian Buffer [Digital image]
Retrieved from: http://ian.umces.edu/imagelibrary/displayimage-2469.html