The rising emissions of greenhouse gases and the resultant climate change are adding to the threats to the world's dwindling stocks of fish, the UN Environment Programme (UNEP) said in a report made public on Friday.
The main problem is the changes in circulation brought on by the fading and falling of the ocean's natural pumping system, which may "seriously impact" three-fourths of the globe's key fishing grounds.
"These natural pumps, dotted at sites across the world, including the Arctic and the Mediterranean, bring nutrients to fisheries and keep them healthy by flushing out wastes and pollution," UNEP said.
In addition, higher sea surface temperatures "threaten to bleach and kill up to 80 per cent of the globe's coral reefs," which often serve as nurseries for fish.
And there is concern that carbon dioxide emissions will increase the acidity of seawater, which will affect shell-forming marine life and plankton, a key part of the food chain.
The report, titled In Dead Water, is the first to attempt to map the impacts of pollution, alien infestations, overfishing and climate change on the world's seas and oceans.
"The worst concentration of cumulative impacts of climate change with existing pressures of over-harvest, bottom trawling, invasive species infestations, coastal development and pollution appear to be concentrated in 10-15 per cent of the oceans," the report says.
That figure is substantially higher than had been assumed and includes large portions of what are currently considered the world's most valuable fishing grounds.
According to UN Under-Secretary General and UNEP Executive Director Achim Steiner, "Climate change threatens coastal infrastructure, food and water supplies and the health of people across the world.
"Millions of people, including many in developing countries, derive their livelihoods from fishing while around 2.6 billion people get their protein from seafood," he stressed.
The report was issued on the third, and final, day of the UNEP Governing Council/Global Ministerial Environment Forum, held in Monaco under the theme "Mobilizing Finance for the Climate Challenge."
The meeting was attended by some 100 environment ministers as well as senior figures from business, organized labour, science and civil society.
Güncelleme Tarihi: 24 Şubat 2008, 14:59