Nature 407, 932 (2000) © Macmillan Publishers Ltd. Global warming identified as main threat to coral reefs PETER POCKLEY [BALI] A report released this week paints a bleak picture of the condition of the world's coral reefs. And it names global warming as the culprit behind much of the damage. Only two years after a survey of the world's coral reefs found 11% had been destroyed before 1998, a more extensive assessment by 80 countries of their own reefs — most for the first time — has raised the total to 27% "effectively lost" by late 2000. The latest measurements come from the Global Coral Reef Monitoring Network, the operational unit of the International Coral Reef Initiative, and they take account of the massive bleaching of corals that took place in 1998. The network identified a further 14% of reefs that are at "critical" risk of being lost within 2–10 years, and 18% more as being "threatened" in 10–30 years. The details were released this week at the ninth International Coral Reef Symposium in Bali, Indonesia, an island that sits at the centre of the archipelago harbouring the greatest diversity of coral species. The coordinator of both surveys, Clive Wilkinson of the Australian Institute of Marine Science (AIMS), says the agenda up to 1998 had primarily been to curb human impacts on reefs. Damage is now documented from over-fishing for subsistence and export, from the live fish trade, from fishing by explosion and poisoning, as well as from sewage, and excessive sediments and nutrients running off urban and agricultural development. Although these influences remain, the new report argues that the main problem has now become global climate change, to which corals are proving acutely sensitive. Terry Done, also of AIMS and president of the conference, joined Wilkinson in stressing the need to curb greenhouse gas emissions. The problems are most severe in the wider Indian Ocean, where there has been 59% loss but "reasonable chances of recovery for remote reefs", according to the report. Next in order are reefs in the Middle East (35% damage and "low chances for short-term recovery"), and Southeast and East Asia (34% loss "with reasonable chances for slow recovery on remote reefs"). The Caribbean/Atlantic reported a loss of 22%, mostly from human impact — but with relatively fast recovery. In contrast, the extensive reefs in the Pacific and off Australia are reported as being "in reasonably good health with a positive outlook unless global climate change events like those of 1998 strike these areas". Wilkinson says it is significant that countries are "no longer in a state of denial and are appealing for help", as exemplified by Indonesian officials at the conference. http://coral.aoml.noaa.gov/gcrmn/ --------------------------------------------------------------------- Mulai langganan: kirim e-mail ke [EMAIL PROTECTED] Stop langganan: kirim e-mail ke [EMAIL PROTECTED] Archive ada di http://www.mail-archive.com/envorum@ypb.or.id
