Navigation Links
Studying rivers for clues to global carbon cycle
Date:2/8/2008

EVANSTON, Ill. --- In the science world, in the media, and recently, in our daily lives, the debate continues over how carbon in the atmosphere is affecting global climate change. Studying just how carbon cycles throughout the Earth is an enormous challenge, but one Northwestern University professor is doing his part by studying one important segment -- rivers.

Aaron Packman, associate professor of civil and environmental engineering in the McCormick School of Engineering and Applied Science, is collaborating with ecologists and microbiologists from around the world to study how organic carbon is processed in rivers.

Packman, who specializes in studying how particles and sediment move around in rivers, is co-author of a paper on the topic published online in the journal Nature Geoscience.

The paper evaluates our current understanding of carbon dynamics in rivers and reaches two important conclusions: it argues that carbon processing in rivers is a bigger component of global carbon cycling than people previously thought, and it lays out a framework for how scientists should go about assessing those processes.

Much more is known about carbon cycling in the atmosphere and oceans than in rivers. Evaluating large-scale material cycling in a river provides a challenge -- everything is constantly moving, and a lot of it moves in floods. As a result, much of what we know about carbon processing in rivers is based on what flows into the ocean.

But thats not really enough, Packman said. You miss all this internal cycling.

In order to understand how carbon cycles around the globe -- through the land, freshwater, oceans and atmosphere -- scientists need to understand how it moves around, how its produced, how its retained in different places and how long it stays there.

In rivers, carbon is both transformed and consumed. Microorganisms like algae take carbon out of the atmosphere and incorporate it into their own cells, while bacteria eat dead organic matter and then release CO2 back into the atmosphere.

Its been known for a long time that global carbon models dont really account for all the carbon, Packman said. Theres a loss of carbon, and one place that could be occurring is in river systems. Even though river waters contain a small fraction of the total water on earth, they are such dynamic environments because microorganisms consume and transform carbon at rapid rates.

Were evaluating how the structure and transport conditions and the dynamics of rivers create a greater opportunity for microbial processing, Packman said.

Packman is the first to admit that studying microorganisms, carbon and rivers sounds more like ecology than engineering. But such problems require work from all different areas, he said.

Were dealing with such interdisciplinary problems, tough problems, so we have to put fluid mechanics, transport, ecology and microbiology together to find this overall cycling of carbon, he said. People might say its a natural science paper, but to me its a modern engineering paper. To understand whats going on with these large-scale processes, we have to analyze them quantitatively, and the tools for getting good estimates have been developed in engineering.

Packman was introduced to the co-authors of the paper -- ecologists who study how dead leaves and soil drive stream ecology and who come from as far away as Spain and Austria -- about 10 years ago through the activity of the Stroud Water Research Center in Pennsylvania.

Since then, they have collaborated on many similar projects around river structure and transport dynamics. They are currently working on a project funded by the National Science Foundation on the dynamics of organic carbon in rivers and trying to understand how carbon delivered from upstream areas influence the ecology of downstream locations.

The broadest idea is really part of global change efforts to understand carbon cycling over the whole Earth, which is an enormous challenge, Packman said.


'/>"/>

Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology news :

1. MIT applies engineering approach to studying biological pathways
2. Jefferson scientists studying the effects of high-dose vitamin C on non-Hodgkin lymphoma patients
3. Childrens Hospital studying drug with the potential to prevent/delay onset of type 1 diabetes
4. Researchers studying how singing bats communicate
5. Jefferson urologists studying regenerated neo-bladder to help spinal cord injury patients
6. Studying component parts of living cells with carbon nanotube cellular probes
7. Chemicals used as fire retardants could be harmful, UC-Riverside researchers say
8. Scientists from the UGR prove that rivers do not act as barriers for groundwater flow
9. UC-Riverside partners with Chinese university to address Chinas environmental problems
10. UC Riverside biologist receives prestigious MacArthur Fellowship
11. Tomato pathogen genome may offer clues about bacterial evolution at dawn of agriculture
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/9/2016)... leader in attendance control systems is proud to announce the introduction of fingerprint attendance ... the right employees are actually signing in, and to even control the opening of ... ... ... Photo - ...
(Date:6/3/2016)... , June 3, 2016 ... von Nepal hat ... Lieferung hochsicherer geprägter Kennzeichen, einschließlich Personalisierung, Registrierung ... in der Produktion und Implementierung von Identitätsmanagementlösungen. ... Ausschreibung im Januar teilgenommen, aber Decatur wurde ...
(Date:6/2/2016)... -- Perimeter Surveillance & Detection Systems, Biometrics ... Support & Other Service  The latest report ... analysis of the global Border Security market . ... $17.98 billion in 2016. Now: In November ... software and hardware technologies for advanced video surveillance. ...
Breaking Biology News(10 mins):
(Date:6/27/2016)... , June 27, 2016  Liquid Biotech ... announced the funding of a Sponsored Research Agreement ... circulating tumor cells (CTCs) from cancer patients.  The ... in CTC levels correlate with clinical outcomes in ... These data will then be employed to support ...
(Date:6/24/2016)... ... ... While the majority of commercial spectrophotometers and fluorometers use the z-dimension of 8.5 ... end machines that use the more unconventional z-dimension of 20mm. Z-dimension or ... the cuvette holder. , FireflySci has developed several Agilent flow cell product lines ...
(Date:6/23/2016)...   Boston Biomedical , an industry leader ... target cancer stemness pathways, announced that its lead ... Designation from the U.S. Food and Drug Administration ... gastroesophageal junction (GEJ) cancer. Napabucasin is an orally ... stemness pathways by targeting STAT3, and is currently ...
(Date:6/23/2016)... ... June 23, 2016 , ... Charm ... Mold) microbial test has received AOAC Research Institute approval 061601. , “This is ... last year,” stated Bob Salter, Vice President of Regulatory and Industrial Affairs. “The ...
Breaking Biology Technology: