Monday, May 20, 2013

Research into carbon storage in arctic tundra reveals unexpected insight into ecosystem resiliency

Science Daily: When UC Santa Barbara doctoral student Seeta Sistla and her adviser, environmental studies professor Josh Schimel, went north not long ago to study how long-term warming in the Arctic affects carbon storage, they had made certain assumptions.

"We expected that because of the long-term warming, we would have lost carbon stored in the soil to the atmosphere," said Schimel. The gradual warming, he explained, would accelerate decomposition on the upper layers of what would have previously been frozen or near-frozen earth, releasing the greenhouse gas into the air. Because high latitudes contain nearly half of all global soil carbon in their ancient permafrost -- permanently frozen soil -- even a few degrees' rise in temperature could be enough to release massive quantities, turning a carbon repository into a carbon emitter.

"The Arctic is the most rapidly warming biome on Earth, so understanding how permafrost soils are reacting to this change is of major concern globally," Sistla said.

To test their hypothesis, the researchers visited the longest-running climate warming study in the tundra, the U.S. Arctic Long-Term Ecological Research site at Toolik Lake in northern Alaska. This ecosystem-warming greenhouse experiment was started in 1989 to observe the effects of sustained warming on the Arctic environment.

What they initially found was typical of Arctic warming: low-lying, shallow-rooted vegetation giving way to taller plants with deeper roots; greater wood shrub dominance; and increased thaw depth. What they weren't expecting was that two decades of slow and steady warming had not changed the amounts of carbon in the soil, despite changes in vegetation and even the soil food web.

The answer to that mystery, according to Sistla, might be found in the finer workings of the ecosystem: Increased plant growth appears to have facilitated stabilizing feedbacks to soil carbon loss. Their research is published in the recent edition of the journal Nature.

"We hypothesize that net soil carbon hasn't changed after 20 years because warming-accelerated decomposition has been offset by increased carbon inputs to the soil due to a combination of increased plant growth and changing soil conditions," Sistla said....

Alaskan tundra, shot by Maisotti, Wikimedia Commons, under the Creative Commons Attribution 3.0 Unported license


Anonymous said...

I'm very pleased to discover this web site. I need to to thank you for your time for this particularly fantastic read!! I definitely liked every part of it and i also have you book-marked to look at new stuff on your web site.

Take a look at my web blog Click Here

Anonymous said...

great put up, very informative. I wonder why the other specialists
of this sector don't notice this. You should continue your writing. I'm sure, you've a great readers' base already!

Here is my page: Visit here

Anonymous said...

Great article. I am going through some of these issues as well.

Also visit my web blog :: visit this site

Anonymous said...

I could not refrain from commenting. Perfectly written!

Here is my web-site: click this Site

Anonymous said...

Generally I do not read article on blogs,
however I would like to say that this write-up very forced me
to take a look at and do so! Your writing style has been amazed me.
Thank you, quite nice article.

Review my site; click the site

Anonymous said...

I all the time used to read paragraph in news papers
but now as I am a user of internet therefore from now I am using net for posts,
thanks to web.

Also visit my blog post; about

Anonymous said...

What's Happening i'm new to this, I stumbled upon this I have discovered
It positively helpful and it has helped me out loads.
I'm hoping to contribute & assist different users like its aided me. Great job.

My website; about