PDA

View Full Version : Salt wrecking Antarctic explorers legacy


Gservo
10th November 2002, 02:14 PM
The huts that Scott and Shackleton used during their Antarctic expeditions almost 100 years ago are in danger of falling into ruin. The walls of the huts are being eaten away by salt and a mysterious fungus, adding to the damage they already suffer from exposure to the elements.

The findings, by an international team, will be crucial in shaping the Antarctic Heritage Trust's restoration project for the huts, launched this year. "The situation has become critical," says the trust. "We can't assume that because these huts have lasted this long they will last forever."

The huts affected include Scott's shelter at Hut Point, built during his Discovery expedition, from 1901 to 1904, and another at Cape Evans from his later Terra Nova expedition which began in 1910. A third hut at Cape Royds is from Shackleton's 1907 to 1909 Nimrod expedition.

The Antarctic climate is thought to be a good preserver, with the cold and dry air stopping unopened cans of food and reindeer sleeping bags, for example, from rotting. But the huts are in notoriously salty areas - so much salt blows in from the sea that it forms crusts on the ground. And it is this salt-laden spray that is making the huts' walls splinter and shred.


Freeze-thaw


"It was originally thought to be a freeze-thaw problem," says study author Benjamin Held, a plant pathologist at the University of Minnesota. But he and his team from Minnesota and the University of Waikato, New Zealand, found that the spray has been seeping into the wood and reacting with hemicellulose and lignin, separating wood cells from each other and causing fibres to fray.

"The levels of salt in the wood are phenomenal," says Held. The process of decay is neither well known nor well understood, although at least one piece of research carried out about 10 years ago describes how salt crystals seriously weakened some wharf pilings in the US
The team also found what they believe to be Phialophora fungus eating away at the wooden foundations. "It's weird," says Held. "There is no wood native to the Antarctic. So why are there fungi there that can cause soft rot?" The researchers are working to identify the fungus more precisely so that it can be dealt with effectively.

The team is testing some silicone-based wood protectants in the lab to see if they can stop the damage. But even if they find a successful treatment there might be objections to its use, since conservators are traditionally nervous about doing anything that cannot be reversed.

Instead they might have to settle for erecting wind barriers to keep the spray off the walls, and ask the thousands of visitors to the huts each year to wear protective covers over their boots to prevent them bringing contamination inside.

Journal reference: Polar Record (vol 38, p 313)

Fireblade
10th November 2002, 04:25 PM
interesting stuff there m8... but what's it got t' do wi' 'CD/DVD Technologies' :D I could suggest they build the new wind barriers outta the millions of freebie AOL CD's to be found of course - that might cover ye :lol:

Gservo
10th November 2002, 05:21 PM
lesson of today, dont post whore unless fully awake