permaculture

[Lawrence London <lfljvenaura@gmail.com>]

BBC News - Centuries-old frozen plants revived
http://www.bbc.co.uk/news/science-environment-22656239

Plants that were frozen during the "Little Ice Age" centuries ago have been
observed sprouting new growth, scientists say.

Samples of 400-year-old plants known as bryophytes have flourished under
laboratory conditions.

Researchers say this back-from-the-dead trick has implications for how
ecosystems recover from the planet's cyclic long periods of ice coverage.

The findings appear in Proceedings of the National Academy of
Sciences<http://www.pnas.org/cgi/doi/10.1073/pnas.1304199110>
.

They come from a group from the University of Alberta, who were exploring
an area around the Teardrop Glacier, high in the Canadian Arctic.

The glaciers in the region have been receding at rates that have sharply
accelerated since 2004, at about 3-4m per year.

That is exposing land that has not seen light of day since the so-called
Little Ice Age, a widespread climatic cooling that ran roughly from AD 1550
to AD 1850.

"We ended up walking along the edge of the glacier margin and we saw these
huge populations coming out from underneath the glacier that seemed to have
a greenish tint," said Catherine La Farge, lead author of the study.

Bryophytes are different from the land plants that we know best, in that
they do not have vascular tissue that helps pump fluids around different
parts of the organism.

They can survive being completely desiccated in long Arctic winters,
returning to growth in warmer times, but Dr La Farge was surprised by an
emergence of bryophytes that had been buried under ice for so long.

"When we looked at them in detail and brought them to the lab, I could see
some of the stems actually had new growth of green lateral branches, and
that said to me that these guys are regenerating in the field, and that
blew my mind," she told BBC News.

"If you think of ice sheets covering the landscape, we've always thought
that plants have to come in from refugia around the margins of an ice
system, never considering land plants as coming out from underneath a
glacier."

But the retreating ice at Sverdrup Pass, where the Teardrop Glacier is
located, is uncovering an array of life, including cyanobacteria and green
terrestrial algae. Many of the species spotted there are entirely new to
science.

"It's a whole world of what's coming out from underneath the glaciers that
really needs to be studied," Dr La Farge said.

"The glaciers are disappearing pretty fast - they're going to expose all
this terrestrial vegetation, and that's going to have a big impact."
More on This Story
Related Stories

   -  Canadian glaciers face 'big
losses'<http://www.bbc.co.uk/news/science-environment-21699115>
   07 MARCH 2013, SCIENCE & ENVIRONMENT
   -  Operation Iceberg diary: Part Four<http://www.bbc.co.uk/nature/19149135>
   17 AUGUST 2012, FEATURES
   -  Ice retreat creates new CO2
store<http://www.bbc.co.uk/2/hi/science/nature/8352469.stm>
   17 NOVEMBER 2009, SCI/TECH

 Related Internet links

   - Regeneration of Little Ice Age bryophytes emerging from a polar
   glacier with implications of totipotency in extreme
environments<http://www.pnas.org/cgi/doi/10.1073/pnas.1304199110>
   - Catherine La Farge at University of
Alberta<http://www.biology.ualberta.ca/faculty/catherine_lafarge/>