Living under a rock: more hints about global warming

If you're the kind of person that buys fertilizer from the gardening section of the local home improvement store, you can surely agree with one simple fact: plants need nitrogen.

But a new study suggests that soil and plants aren't getting nitrogen from microbes or atmospheric air alone.

Researchers at the University of California, Davis say that forest trees in the Pacific Northwest were found to access nitrogen from sedimentary rocks in the area. The element helps plants grow more quickly -- it's used to construct DNA and proteins -- and absorb more carbon dioxide from the atmosphere.

"To put it in perspective, there is enough nitrogen contained in one inch of the rocks at our study site to completely support the growth of a typical coniferous forest for about 25 years,” biogeochemist and study co-author Randy Dahlgren said in a statement.

Previously, it was thought that nitrogen could only be acquired through rainwater or certain groups of plants and animals ("fixation"), pathways that are limited in impact.

But sedimentary rock covers 75 percent of the Earth's land surface. Now found to play a part in the cycle that affects global climate change, the rocks may force scientists to update their climate projections -- as well as investigate new solutions for capturing and storing carbon on land.

NPR's Richard Harris reports:

This affects how the forests of the world could react to climate change. Trees are gobbling up a fair amount of the carbon dioxide that we pour into the atmosphere, but scientists have been worried that in the next few decades, they'd start to run out of the nitrogen they need to keep fueling this growth spurt. It turns out maybe not.

Nitrogen Study Could 'Rock' A Plant's World [NPR]

Photo: Scott Morford/UC Davis

This post was originally published on Smartplanet.com