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Environmental Action: Coral growth and CO2 levels in the Ocean
Bonaire Talk: Environmental Action: Archives 2008-2009: Coral growth and CO2 levels in the Ocean
Top of pagePrevious messageNext messageBottom of page Link to this message  By Daniel J. Zielinski (BonaireTalker - Post #48) on Monday, January 5, 2009 - 1:01 pm:     Edit PostPrint Post

Heard this on the news over the weekend and did a quick search for something on the internet. It's not good news...however, I haven't checked with Fred Singer or the Heartland Institute or ExxonMobil. I'm sure they can find a positive spin to this decline...wait a minute...I've got one! No more worry about fire coral stings or scratches from live coral! Who's with me!?!?!

Slowdown of coral growth extremely worrying, say scientists

Coral growth across the Great Barrier Reef has suffered a "severe and sudden" slowdown since 1990 that is unprecedented in the last four centuries, according to scientists.

The researchers analysed the growth rates of 328 coral colonies on 69 individual reefs that make up the 1,250 mile-long Great Barrier Reef, off north-east Australia. They found that the rate at which the corals were laying down calcium in their skeletons dropped by 14.2% between 1990 and 2005.

Corals around the world are severely threatened by coastal pollution, warming seas and over-exploitation, but the most probable explanation for the drop in the growth rate of the corals' calcium carbonate skeletons is acidification of the water due to rising carbon dioxide levels in the atmosphere. More acid water makes it more difficult for the coral polyps to grab the minerals they need to build their skeletons from the sea water.

"Our data shows that growth and calcification of massive Porites in the GBR [Great Barrier Reef] are already declining and are doing so at a rate unprecedented in coral records reaching back 400 years," wrote Dr Glenn De'ath from the Australian Institute of Marine Science in Townsville, Queensland, and his colleagues in the journal Science. "Verification of the causes of this decline should be made a high priority."

Porites corals can be centuries old and grow into 6m tall mounds. Rather like a tree ring, each year's growth is visible as a band, so by drilling into the corals the scientists could examine the extent of growth in specific years. The team used x-rays and a technique called gamma densitometry to measure annual growth and skeletal density, which then allowed them to calculate the amount of calcification annually. They found that the calcification rate rose 5.4% between 1900 and 1970, but this dropped by 14.2% between 1990 and 2005. The drop was mainly due to a growth slowdown from 1.43cm a year to 1.24cm. The researchers measured the same effect in both nearshore and offshore reefs, suggesting it is not due to pollution from the land.

"This study has provided the first really rigorous snapshot of how calcification might be changing," marine biologist Ove Hoegh-Guldberg of the University of Queensland in Australia told Science. "The results are extremely worrying."

http://www.guardian.co.uk/environment/2009/jan/01/1

 

Top of pagePrevious messageNext messageBottom of page Link to this message  By Carole B. (Supreme BonaireTalker - Post #7024) on Tuesday, January 6, 2009 - 2:17 am:     Edit PostPrint Post

Thanks for posting the article, Daniel. Very disturbing, indeed. Change must occur immediately.

I do believe the first step for Bonaire is now in motion. A "temporary" treatment system is to be transported to the island to operate until the main/permanent waste water treatment plant is build, up and running. It's a start in the right direction. cb

 

Top of pagePrevious messageNext messageBottom of page Link to this message  By Pauline Kayes (Experienced BonaireTalker - Post #150) on Tuesday, January 6, 2009 - 7:33 am:     Edit PostPrint Post

Carole, yes, it is a first step that will not stop the degradation of the reefs unless the seeping landfill at Lagoen is also addressed immediately. All that trash and toxic chemicals, etc. are percolating downward through the rock into the water table and into the sea.

Bonaire has probably about 1 or 2 years to turn this around. Let's hope they do! And let's keep talking it up so the public and tourist pressure mounts.

SOS Campaign To Save Bonaire's Reefs
SOSBonaireReef@gmail.com

 


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