Navigation Links
Amazon powers tropical ocean's carbon sink
Date:7/21/2008

Nutrients from the Amazon River spread well beyond the continental shelf and drive carbon capture in the deep ocean, according to the authors of a multi-year study.

The finding does not change estimates of the oceans' total carbon uptake, but it reveals the surprisingly large role of tropical oceans and major rivers.

The tropical North Atlantic had been considered a net emitter of carbon from the respiration of ocean life. A 2007 study estimated that ocean's contribution to the atmosphere at 30 million tons of carbon annually.

The new study, appearing in PNAS Early Edition the week of July 21, finds that almost all the respiration is offset by organisms called diazotrophs, which pull nitrogen and carbon from the air and use them to make organic solids that sink to the ocean floor.

Diazotrophs "fix" nitrogen from the air, enabling them to thrive in nutrient-poor waters. They also require small amounts of phosphorus and iron, which the Amazon River delivers far offshore.

That is all the diazotrophs need to pull carbon from the air and sink it in the ocean.

The other great tropical rivers of the world also may contribute to carbon capture, said senior author Doug Capone, professor in the USC Wrigley Institute for Environmental Studies at the University of Southern California, adding that studies on such rivers are in progress.

The study's results present new options for the controversial practice of iron fertilization. Some biologists believe that seeding the oceans with iron could increase production of carbon-fixing organisms and help mitigate climate change.

Upwelling circulation in cooler waters makes them unlikely candidates for long-term carbon capture, said Capone, who explained that a permanent carbon sink instead may be more feasible in the warm oceans.

Capone said that iron fertilization would increase diazotroph activity and that the stratified tropical waters should be able to keep captured carbon solids from returning to the surface in the short term.

"The most appropriate places are probably not the high latitudes but rather the low-latitude areas where nitrogen fixation is a predominant process," Capone said.

But Capone also noted the risks of iron fertilization, including increased production of other greenhouse gases and unpredictable effects on the food web.

Nevertheless, he said, "if we choose as a human society to fertilize areas of the oceans, these are the places that probably would get a lot more bang for the buck in terms of iron fertilization than we would at high latitudes."


'/>"/>

Contact: Carl Marziali
marziali@usc.edu
213-740-4751
University of Southern California
Source:Eurekalert

Related biology news :

1. Amazon forest shows unexpected resiliency during drought
2. Univ. of Arizona receives $2.5 million to study Amazon forests and climate change
3. Present-day species of piranha result from a marine incursion into the Amazon Basin
4. Amazon corridors far too narrow, warn scientists
5. Workshop assesses interactions between climate, forests and land use in the Amazon Basin
6. Crystal (eye) ball: Study says visual system equipped with future seeing powers
7. Tropical insects go the distance to inform rainforest conservation
8. New study warns limited carbon market puts 20 percent of tropical forest at risk
9. Tropical crab invades Georgia oyster reefs -- but the long-term impact cant be predicted
10. Spatial patterns in tropical forests can help to understand their high biodiversity
11. Researchers discover forests of endangered tropical kelp
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:8/23/2017)... -- The general public,s help is being enlisted in what,s thought to be ... on the human body –and are believed to affect health.  ... The Microbiome Immunity Project is the largest study ... gut. The project's goal is to help advance scientific knowledge of the ... ...
(Date:6/30/2017)... ARLINGTON, Va. , June 30, 2017 /PRNewswire-USNewswire/ ... a leading developer and supplier of face and ... the ATA Featured Product provider program. ... created an innovative way to monitor a driver,s ... benefit greatly from being able to detect fatigue ...
(Date:5/23/2017)... 23, 2017  Hunova, the first robotic gym for the rehabilitation and ... launched in Genoa, Italy . The first 30 robots ... the USA . The technology was developed and patented ... the IIT spin-off Movendo Technology thanks to a 10 million euro investment ... please click: ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... 11, 2017 , ... ComplianceOnline’s Medical Device Summit is back for its 4th ... in San Francisco, CA. The Summit brings together current and former FDA office bearers, ... and government officials from around the world to address key issues in device compliance, ...
(Date:10/11/2017)... INDIANAPOLIS , Oct. 11, 2017  VMS BioMarketing, a ... of a nationwide oncology Clinical Nurse Educator (CNE) network, which ... growing need for communication among health care professionals to enhance ... physicians, nurses, office staff, and other health care professionals to ... for breast cancer. ...
(Date:10/11/2017)... ... , ... Disappearing forests and increased emissions are the main causes of the ... Especially those living in larger cities are affected by air pollution related diseases. , ... pollution-affected countries globally - decided to take action. , “I knew I had to ...
(Date:10/11/2017)... ... October 11, 2017 , ... Singh Biotechnology today ... designation to SBT-100, its novel anti-STAT3 (Signal Transducer and Activator of Transcription 3) ... able to cross the cell membrane and bind intracellular STAT3 and inhibit its ...
Breaking Biology Technology: