Dead Zone (ecology)
Dead zones are hypoxic (low-oxygen) areas in the world's oceans and large lakes, caused by "excessive nutrient pollution from human activities coupled with other factors that deplete the oxygen required to support most marine life in bottom and near-bottom water. (NOAA)." In the 1970s oceanographers began noting increased instances of dead zones. These occur near inhabited coastlines, where aquatic life is most concentrated. (The vast middle portions of the oceans, which naturally have little life, are not considered "dead zones".)
In March 2004, when the recently established UN Environment Programme published its first Global Environment Outlook Year Book (GEO Year Book 2003), it reported 146 dead zones in the world's oceans where marine life could not be supported due to depleted oxygen levels. Some of these were as small as a square kilometre (0.4 mi²), but the largest dead zone covered 70,000 square kilometres (27,000 mi²). A 2008 study counted 405 dead zones worldwide.
Other articles related to "dead":
... Deadzones are reversible ... The Black Sea deadzone, previously the largest in the world, largely disappeared between 1991 and 2001 after fertilizers became too costly to use following the collapse of the Soviet Union and the demise of ... From 1985 to 2000, the North Sea deadzone had nitrogen reduced by 37% when policy efforts by countries on the Rhine River reduced sewage and industrial emissions of ...
Famous quotes containing the words dead and/or zone:
“she cannot understand
What she wants or why she wanders to that undiscovered land,
For the parties there are not at all the sort of thing she planned,
In the land where the dead dreams go.”
—Alfred Noyes (18801958)
“Light is meaningful only in relation to darkness, and truth presupposes error. It is these mingled opposites which people our life, which make it pungent, intoxicating. We only exist in terms of this conflict, in the zone where black and white clash.”
—Louis Aragon (18971982)