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Raül Romeva Cap a l'extinció massiva de la vida marina en, només, una generació!
Raül Romeva

La situació dels nostres mars i oceans és molt pitjor del que ens pensàvem (fins i tot els qui érem més realistes). Ens ho confirma un panel d'experts que compara l'actual situació amb les extincions massives que hi ha hagut al llarg de la història i que recull un article a The Independent.

Oceans on brink of catastrophe

Marine life facing mass extinction 'within one human generation' / State of seas 'much worse than we thought', says global panel of scientists

By Michael McCarthy, Environment Editor
Tuesday, 21 June 2011

The world's oceans are faced with an unprecedented loss of species comparable to the great mass extinctions of prehistory, a major report suggests today. The seas are degenerating far faster than anyone has predicted, the report says, because of the cumulative impact of a number of severe individual stresses, ranging from climate warming and sea-water acidification, to widespread chemical pollution and gross overfishing.

The coming together of these factors is now threatening the marine environment with a catastrophe "unprecedented in human history", according to the report, from a panel of leading marine scientists brought together in Oxford earlier this year by the International Programme on the State of the Ocean (IPSO) and the International Union for the Conservation of Nature (IUCN).

The stark suggestion made by the panel is that the potential extinction of species, from large fish at one end of the scale to tiny corals at the other, is directly comparable to the five great mass extinctions in the geological record, during each of which much of the world's life died out. They range from the Ordovician-Silurian "event" of 450 million years ago, to the Cretaceous-Tertiary extinction of 65 million years ago, which is believed to have wiped out the dinosaurs. The worst of them, the event at the end of the Permian period, 251 million years ago, is thought to have eliminated 70 per cent of species on land and 96 per cent of all species in the sea.

The panel of 27 scientists, who considered the latest research from all areas of marine science, concluded that a "combination of stressors is creating the conditions associated with every previous major extinction of species in Earth's history". They also concluded:

* The speed and rate of degeneration of the oceans is far faster than anyone has predicted;

* Many of the negative impacts identified are greater than the worst predictions;

* The first steps to globally significant extinction may have already begun.

(keep reading...)

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Font: Raül Romeva
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