Nitrogen found in rocks can boost the growth of forest trees and enable them to pull more carbon dioxide from the atmosphere, reveals study.
Nitrogen, found in such vital molecules as DNA and protein, is necessary for all life and is used worldwide as a fertilizer for food crops. It is the nutrient that most often limits plant growth in natural ecosystems.
If trees can access more nitrogen than previously thought, that could lead to more storage of carbon on land and less carbon remaining in the atmosphere.
It was previously believed that nitrogen could only enter ecosystems from the atmosphere.
"We were really shocked; everything we've ever thought about the nitrogen cycle and all of the textbook theories have been turned on their heads by these data," said Professor Benjamin Houlton, a biogeochemist and one of the study's co-authors.
"Findings from this study suggest that our climate-change models should not only consider the importance of nitrogen from the atmosphere, but now we also have to start thinking about how rocks may affect climate change," he said.
The UC David study also found that rocks enriched in nitrogen have a profound effect on the fertility of forests.
"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," said Professor Randy Dahlgren, a biogeochemist and a study co-author.
The productivity of forests growing on nitrogen-rich rock was approximately 50 percent higher than the productivity of forests growing on nitrogen-poor rocks throughout Northern California and into Oregon, the report said.
The study has been published in the journal Nature.