Dead Zones

Dead zones, or ‘hypoxic’ (low-oxygen) zones, are coastal areas of oceans, seas, and large lakes that no longer have sufficient oxygen to support many forms of life. Scientists first began to note the existence of dead zone in the 1970s, and as of this writing there are approximately 400 dead zones that have been accounted for world wide. The cause of dead zones has been largely attributed to an increase in chemical pollution, (particularly nitrogen and phosphorus) in the water, which causes an algae ‘bloom’ (also known as the process of eutrophication). Water born nitrogen and phosphorous are primarily the result of fertilizer leakage from farming operations that drain into waterways. Run- off from agricultural systems carry these nutrients through the streams and rivers until reaching the coast. The algae then proceeds to consume available oxygen, taking it away from other creatures, such as fish and mollusks, eventually causing massive die offs of aquatic life. Scientists have noted that the current push for Biofuels , specifically corn-based ethanol, will likely dramatically increase the amount of synthetic nitrogen applied to US soils, thereby augment the dead zone in the Gulf of Mexico.

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