Sink or source? A new model to measure organic carbon in surface waters
A new carbon model allows scientists to estimate sources and losses of organic carbon in surface waters in the United States. Study results indicate that streams act as both sources and sinks for organic carbon. "Model estimates help managers and researchers track carbon transport in streams, which is information that is ultimately needed to improve our understanding of the fate of rising carbon dioxide levels in the atmosphere," said Dr. Richard Smith, a USGS hydrologist and coauthor of the study. "The study contributes new information on the role of rivers as sources and sinks for organic carbon at regional and continental scales, for which scientific knowledge is rather limited."
Findings show that in-stream photosynthesis by algae is a major contributor of organic carbon in large rivers of the United States. It is the largest source of organic carbon delivered to coastal waters from the Mississippi-Atchafalaya River Basin and the Pacific Northwest.
Terrestrial sources of carbon, such as from forests and wetlands, are dominant in all other coastal waters, including waters of the North Atlantic, the South Atlantic Gulf, California, the Texas Gulf, and the Great Lakes.
The results also provide estimates of how much of the organic carbon transported in streams is then permanently removed from the water column. The removed carbon is either sequestered in sediments over long time periods or oxidized and returned to the atmosphere as carbon dioxide. The specific fate of the carbon is not quantified in the current model.
Study findings are estimated using a hydrological mass-balance model based on long-term monitoring at 1,125 stream locations and national geospatial information, including a river network of approximately 62,000 reaches and their connecting drainages, land cover, climate, soils, and estimates of the supply of carbon to streams from primary production.
Source: United States Geological Survey
- Sink or source? A new model to measure organic carbon in surface watersfrom Science CentricSat, 5 Mar 2011, 9:40:13 EST
- Sink or source? A new model to measure organic carbon in surface watersfrom Science BlogFri, 4 Mar 2011, 9:01:26 EST
- Sink or source? A new model to measure organic carbon in surface watersfrom PhysorgFri, 4 Mar 2011, 8:31:35 EST
Latest Science NewsletterGet the latest and most popular science news articles of the week in your Inbox! It's free!
Learn more about
Check out our next project, Biology.Net
From other science news sites
Popular science news articles
- Pigments, organelles persist in fossil feathers
- Scientists identify possible key in virus, cancer research
- Caltech chemists solve major piece of cellular mystery
- Future climate models greatly affected by fungi and bacteria
- Moffitt makes important steps toward developing a blood test to catch pancreatic cancer early
- Rare nautilus sighted for the first time in 3 decades
- Want a better relationship and a better sex life?
- Impact of sleep disturbance on recovery in veterans with PTSD and TBI
- Study examines breast cancer mortality after ductal carcinoma in situ diagnosis
- Unlike boys, girls lose friends for having sex, gain friends for making out
- Gravitational constant appears universally constant, pulsar study suggests
- California 'rain debt' equal to average full year of precipitation
- Robotic insect mimics Nature's extreme moves
- Special issue: Philae results shed light on the nature of comets
- Researchers find that Earth's magnetic shield is much older than previously thought