A new Science study co-authored by YIBS researchers sheds light on the significant role that rivers in the western United States play in absorbing carbon dioxide from the atmosphere. The research team includes former YIBS Hutchinson Postdoctoral Fellow Taylor Maavara (now an aquatic biogeochemist at the Cary Institute for Ecosystem Studies), current YIBS Donnelley Postdoctoral Fellow Craig Brinkerhoff, and YIBS faculty affiliate Peter Raymond.

For years, most river metabolism data have come from forested, temperate regions of the Northeast, where shaded waterways rich in organic matter tend to release more carbon dioxide than they take in. But by applying machine-learning models to extensive U.S. Geological Survey datasets, the research team produced the largest national analysis of river photosynthesis and respiration to datecapturing monthly and annual rates for all river networks across the contiguous United States.

Their results show that arid and semi-arid regions in the western U.S. tell a very different story. With more sunlight and less organic matter flowing into streams, many western river reaches act as net carbon sinks. The study finds that about 25% of western rivers take in more carbon than they emit each year, compared to 11% in the East, suggesting that carbon-absorbing rivers may be far more common than previously recognized.

These findings indicate that U.S. rivers may be a much smaller source of greenhouse gas emissions than once believed - and that arid regions worldwide could play a surprising role in the global carbon cycle.

For more information, click here for an article published by the Cary Institute of Ecosystem Studies or here for the full study in Science.