disappearing wetlands

DISAPPEARING WETLANDS

Population Pressures and Global Effects

David Severson

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

Types of Wetlands

►Marshes

►Bogs

►Swamps

►Fens © D. Severson, 2011

Why are Wetlands Important?

►Water Purification

►Flood Control

►Shoreline Stabilization

►Wildlife Habitat

►Atmospheric Maintenance


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.

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

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)

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

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?


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