Scientists have built up a comprehensive baseline of microbial life in the Dry Valleys. Photo / Craig Cary
Scientists have built up a comprehensive baseline of microbial life in the Dry Valleys. Photo / Craig Cary
Scientists are completing a sprawling stock-take of one of Antarctica's most famous landmarks: the McMurdo Dry Valleys.
Found within Victoria Land, and to the west of McMurdo Sound which New Zealand's Scott Base overlooks, these rows of largely snow-free valleys form one of the extreme deserts on Earth.
The unique conditions are partly caused by katabatic winds, which are formed when cold, dry, dense air is pulled downhill by the force of gravity.
These ferocious winds can reach speeds of 320km/h, heating as they descend, and evaporating all water, ice and snow.
Temperatures plunge as low as minus 60C over winter – and can rise above 0C for as little as 25 days in the warm season.
And between the seasons, temperatures can swing by 20C in just a day, driving dramatic, rapid-fire cycles of freezing and thawing.
The summer light brings highly damaging levels of UVA and UVB.
It was perhaps this perception of a barren, wind-blasted and seemingly lifeless environment that had long made visitors to the valleys complacent about where they were standing – or what they might be standing on.
Studies have since shown the Dry Valleys are anything but a blank space at the bottom of the world – and are home to such a diversity of bacterial life that scientists themselves have been surprised.
One of those scientists is Professor Craig Cary, a microbiologist whose laboratory at the University of Waikato now contains the most extensive, landscape-scale collection of soil-derived DNA collected in Antarctica.
Cary and his colleagues have spent the past two decades using new genetic tools to learn about life in the valleys – and how it manages to endure, despite the alien odds.
He's also been leading New Zealand's effort in an international programme to effectively map the region's ecosystem, and ability to recover from human impacts.
What was called the Dry Valley Ecosystem Resilience Programme, or DRYver, is set to wrap up at the end of next month, after four seasons of research and thousands of hours spent in the field by more than 20 scientists.
Antarctica's Dry Valleys have been designated a protected area. Photo / Craig Cary
Management of the valleys had become stricter with the region being made an Antarctic Specially Managed Area, or ASMA, and the DRYver project sought to underpin the new protection with more data.
"DRYver was about trying to back our management and policies for operating in the Dry Valleys with better evidence – or give the regulations more teeth," Cary said.
"In the past, much of how we operated in the valleys was derived common sense, but nothing was really underpinned by good science."
The valleys contain soil surfaces made up of a long and rich glacial history – and some were millions of years old.
"Up until recently we operated on all these surfaces in a similar manner," Cary said.
"The results from the DryVer project will identify the very sensitive and resilient surfaces and propose new operating procedures for research teams working in these areas."
The McMurdo Dry Valleys are one of the most extreme desert regions on the planet. Photo / Craig Cary
Cary said research had also revealed that each of the main valleys – the Victoria, Wright and Taylor valleys – had their own localised populations of microbes.
"This was important as it really turned our attention to the importance of biosecurity when moving from one valley to another"
Scientists had only scraped the surface of what there was to learn about the environment and the hardy microbes living within it.
One Kiwi scientist, Waikato University's Adele Williamson, recently began investigating how valley microbes are remarkably able to repair their own damaged DNA.
If she discovers novel modes of action in some of these enzymes, this could provide the basis for developing completely new technologies.
Cary, who is currently in Antarctica to undertake his last baseline survey for DRYver, said the Ministry of Business, Innovation and Employment-supported programme had made a difference.
"It was very ambitious – but it's been very successful and we hope will become the hallmark for other terrestrial system around the continent," he said.
"Our hope is what we end up with is a new set of tools that tell us how we can manage this region better - and point to which areas would be best for visitors to be placed so there's a minimal amount of impact.
"It's an incredibly unique part of the whole continent, and I think we've realised it has the potential to be seriously impacted in our changing world and needs to be preserved."
• Jamie Morton is hosted at Scott Base by Antarctica New Zealand.
