Monday, February 16, 2009

Hypoxia

I originally wrote this for water words, but it works with the article Emily provided. So in 200ish words heres what I have to say about the hypoxia issue...

Dayton to Louisiana!

                Flowing from your drain, storm sewers, and farm fields, to the Great Miami River, south to the Ohio River, meandering southwest towards a rendezvous with the Mississippi, flowing down the estuaries through the depleted Louisiana wetlands, water with excessive nutrient levels meets the poorly mixed water of the Gulf to form the second largest human-caused hypoxic zone in the world. Such hypoxic zones result in massive fish kills and the devastation of shellfish beds. The death toll results from low dissolved oxygen content of hypoxic zones, where dissolved oxygen levels below 2 mg/L are insufficient for the survival of many species. The input of unnaturally high levels nitrogen from sources, such as fertilizers, leads to algal blooms. These photosynthetic algae and phytoplankton form the base of the aquatic food chain and fuel greater respiration in the ecosystem resulting in greater rates of oxygen depletion, espcially as the algal blooms decompose.

Ninety percent of the nutrient input to the Gulf comes from the Mississippi River which drains a huge portion of the North American continent, including water from Dayton. The huge area of the watershed is matched by the huge diversity of the constituent land, which ranges from rural and agricultural to highly urbanized. Thus a wide array of opportunities for improving the situation is presented to us, primarily reducing the use of artificial fertilizers.

1 comment:

  1. Tommy, this is a very good and to the point summary. I thought the most important part of this reading was the fact that there is hypoxia happening everywhere, not just in the Gulf of Mexico and that it's everyone's problem and everyone's fault. Everyone knows about the issues with the Gulf but its interesting to think about the similarities between the problems there and in places like Lake Eerie. I thought this was a really good reading, I liked the biological breakdown of issues.

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