25 Apr 2014:
Soils Release Far More CO2
Than Previously Thought, Researchers Find
As atmospheric CO2 levels rise, soils will likely store less carbon than scientists and climate models had predicted, according to new research
published in Science
. Scientists have long understood that rising carbon dioxide concentrations in the atmosphere spur photosynthesis and plant growth, adding more carbon to the soil. Scientists had thought this soil carbon was relatively stable and could remain locked away
for centuries. But the new study, from researchers at Northern Arizona University shows that increasing soil carbon actually spurs microbes to produce more CO2. Higher atmospheric CO2 levels added roughly 20 percent more carbon to the soil, through increased photosynthesis, but they also increased carbon turnover by microbes by 16.5 percent. Many climate models had previously assumed that far more of the carbon absorbed by soils stayed there for long periods of time. "Our findings mean that nature is not as efficient in slowing global warming as we previously thought," the lead researcher said. "By overlooking this effect of increased CO2 on soil microbes, models used by the Intergovernmental Panel on Climate Change may have overestimated the potential of soil to store carbon and mitigate the greenhouse effect."
Yale Environment 360 is
a publication of the
Yale School of Forestry
& Environmental Studies
Yale Environment 360
articles are now available in Spanish and Portuguese on Universia
, the online educational network. Visit the site.
Business & Innovation
Policy & Politics
Pollution & Health
Science & Technology
Antarctica and the Arctic
Central & South America
Photographer Robert Wintner documents the exquisite beauty and biodiversity of Cuba’s unspoiled coral reefs. View the gallery.
is now available for mobile devices at e360.yale.edu/mobile
The Warriors of Qiugang
, a Yale Environment 360
video, chronicles a Chinese village’s fight against a polluting chemical plant. It was nominated for a 2011 Academy Award for Best Documentary Short.
Watch the video.
Top Image: aerial view of Iceland
. © Google & TerraMetrics.
A three-part series Tainted Harvest
looks at the soil pollution crisis in China, the threat it poses to the food supply, and the complexity of any cleanup. Read the series.