UN report: alarming increase in ocean dead zones

Fertilizers, sewage, fossil fuel burning and other pollutants have led to a doubling in the number of oxygen-deficient coastal areas every decade since the 1960s, resulting in a alarming, rapid increase in "dead zones" in the world's oceans, according to a United Nations Enviroment report issued Thursday in Nairobi.

The full list is expected to be published early next year, but the preliminary findings were released on Thursday at an international marine pollution conference in Beijing that gathered delegates from more than 100 nations.

The study reveals the dead zones may have increased by a third in just two years, threatening fish stock and the people who depend on them. Experts estimate there are 200 dead zones, compared with 149 two years ago.

Ў°Some successes are being scored but in other areas -- like sewage, nutrients from fertilizer run off, animal wastes and atmospheric pollution; sediment mobilization and marine litter -- the problems are intensifying," UNEP Executive Director Achim Steiner said in a statement.

The damage is caused by the rapid growth of tiny plants called phytoplankton. The phytoplankton die and sink to the bottom, and are eaten by bacteria that use up the oxygen in the water. Those phytoplankton blooms are triggered by too many nutrients ЎЄ particularly phosphorous and nitrogen.

The first dead zones were found in northern latitudes like the Chesapeake Bay on the U.S. East Coast and the Scandinavian fjords. Today, the best known is in the Gulf of Mexico, where fertilizers and other algae-multiplying nutrients are dumped by the Mississippi River.

Newly observed dead zones are found in the Archipelago Sea, Finland, Fosu Lagoon, Ghana, Pearl River Estuary and Changjiang River, China, Mersey Estuary, United Kingdom, Elefsis Bay, Greece, Paracas Bay, Peru, Mondego River, Portugal

Montevideo Bay, Uruguay, Western Indian Shelf.

The meeting also received good news from scientists studying the recovery rates of coral reefs damaged by bleaching in the late 1990s by high sea temperatures.

Coral reefs get bleached when warm water forces out tiny algae that live in the coral, providing nutrients and giving reefs their vivid colors. Without the algae, corals whiten and eventually die.

Ў°The new studies indicate healthy ecosystems exposed to minimal contamination are likely to recover and survive better than those stressed by pollution, dredging and other human-made impacts," Steiner said.

Ў°Climate change, and the need to build resilience into habitats and ecosystems so they can cope with the anticipated increase in temperatures likely to come, now represents a further urgent reason to act," Steiner added. Enditem

(Agencies)