Water And Oceanography

The causes of Ocean Dead Zones



Darrin A Yarbrough's image for:
"The causes of Ocean Dead Zones"
Caption: 
Location: 
Image by: 
©  

Dead zones in our oceans are found in areas all over the globe. The majority of these zones are found off the coast of Europe and Eastern North America. Ocean dead zones are causes by pollutants containing high amounts of nitrogen being dumped into major rivers through the continents. These rivers carry the nitrogen rich pollutants down-stream and dump them into the oceans. Once in the ocean concentrated amounts of nitrogen rich nutrients cause algal blooms which deplete the oceans oxygen supply.

The results of this depleted oxygen are a dead zone within the ocean. While fish and other pelagic marine life may be able to escape these toxic regions, slower moving crustaceans and marine life attached to the ocean floor will die out.

There are approximately 150 noted dead zones throughout the oceanic regions. Some items noted that will help reduce the amounts of nitrogen rich pollutants from being concentrated in the ocean areas are,

The reduction in use of fossil fuels and alternative resources for fueling automobiles,

The planting of forests near areas where nitrogen runoff into rivers is significant in order to absorb nutrients before they reach major waterways,

Better sewage treatment plants that would eliminate emission of nitrogen,

Agreements from companies responsible for nitrogen discharge into rivers to reduce the amount of waste and pollutants into rivers.

By creating methods that reduce the discharge of nitrogen into the oceans; these dead zones will begin to diminish, replacing the balance necessary for oxygen to sustain life in oceanic regions. Allowing the nitrogen rich pollutants to continue to be discharged into the ocean could cause the dead zones to increase significantly.

The earliest reported dead zones originated in areas like the Chesapeake Bay, the Baltic Sea, the Black Sea, and the Northern Adriatic Sea. A well known dead zone is in the Gulf of Mexico where the Mississippi River discharges fertilizer from the American Midwest farm industries. Other dead zones have begun to appear off the coast of Asia, Japan, Australia, New Zealand, and South America.

Recently, Scientists have begun to fear that global warming will further aggravate the problem by changing rainfall patterns and significantly increasing runoff into river areas. This combined with an increase in temperature could further contribute to significant decrease in dissolved oxygen levels in ocean regions.

A study conducted in the Gulf of Mexico region suggested that a twenty percent increase in runoff from the Mississippi River coupled with a four degree rise in temperature, could result in a decrease in dissolved oxygen levels by as much as twenty to thirty percent.

This should be a clear and evident warning signal to everyone that the delicate balance of our ecosystems is in severe jeopardy. Without continuing efforts at public awareness as well as adopting new methods in which to use resources, the continuing future of our planet remains in question.




REFERENCE: http://www.msnbc.msn.com/id/4624359/

 

More about this author: Darrin A Yarbrough

ARTICLE SOURCES AND CITATIONS