Dead Zones - Oceanic Graveyards

WHAT are they?

Dead zones are areas in the ocean that can no longer support life- life that once flourished there. To put it bluntly - virtually everything in that area of the ocean is dead or has fled. (Little rhymes amid research are always fun)

A 2008 study counted 405 dead zones in the world. (A 2004 report counted only 150) Many are still small, but will undoubtably increase in size unless something is done.

One of the most concerning dead zones is in the Gulf of Mexico. It is over 22 000 square kilometers - the size of New Jersey. A main cause of this particular dead zone is the massive amount of agriculture that exists in the midwest, near the Mississippi river.

This satellite image shows the dead zone in the Gulf of Mexico, as well as two in Asia

Source

WHY does it happen?

Dead zones are oxygen depleted areas in the ocean that can no longer support the marine life that usually lives there. The water there can also be toxic to animal and human swimmers.

What's to blame?

• Human Activity, especially the agricultural industry. Excess chemicals like nitrogen and phosphorous that runoff from sewage, cars, factories and industrial farming operations either dumping or letting their waste seep into the water.

• Chemical fertilizers are considered to be the main cause of dead zones. There is simply too much toxic runoff for natural filters, like soil, to purify. Once the chemicals enter the water untreated, they eventually run into the ocean and cause an algal bloom; the bloom causes the oxygen-deprived dead zones. Plants and animals that are not able to escape usually die in the toxic environment, those that can flee go elsewhere.

Can this CHANGE?

Dead zones are reversible when the pesticides, manure, and other toxic chemicals that caused them are greatly reduced or eliminated. We just have to DO something about it! The Black Sea dead zone, which was once the largest dead zone in the world, mostly disappeared between 1991 and 2001 when fertilizers became too costly for farmers to use.

Moral of the story: Stop using pesticides, stop supporting the agricultural industry - go organic and local, eat less meat.