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:5/3/2016)... , May 3, 2016  Neurotechnology, a ... the MegaMatcher Automated Biometric Identification System (ABIS) ... large-scale multi-biometric projects. MegaMatcher ABIS can process multiple ... using any combination of fingerprint, face or iris ... MegaMatcher SDK and MegaMatcher Accelerator , ...
(Date:4/28/2016)... BANGALORE, India , April 28, 2016 ... subsidiary of Infosys (NYSE: INFY ), and Samsung ... global partnership that will provide end customers with a ... and payment services.      (Logo: http://photos.prnewswire.com/prnh/20130122/589162 ... for financial services, but it also plays a fundamental part ...
(Date:4/28/2016)... -- First quarter 2016:   , Revenues ... first quarter of 2015 The gross margin was 49% ... and the operating margin was 40% (-13) Earnings per ... from operations was SEK 249.9 M (21.2) , Outlook ... 7,000-8,500 M. The operating margin for 2016 is estimated ...
Breaking Biology News(10 mins):
(Date:5/4/2016)... ... May 04, 2016 , ... The Children’s Tumor Foundation announced its ... tumors to grow on nerves throughout the body. It affects 1 in 3,000 people ... events held during the month of May, as well as online activities, Neurofibromatosis Awareness ...
(Date:5/4/2016)... 2016 According to a new ... - Global Industry Analysis, Size, Share, Growth, Trends, and ... to expand at a CAGR of 17.1% from 2016 ... Metabolomics is the extensive study of small ... or organisms. Together, these small molecules and their interactions ...
(Date:5/4/2016)... ... ... PBI-Gordon Corporation is pleased to announce Doug Obermann has been promoted to ... PBI-Gordon in February 1988, after finishing his masters in agronomy from Iowa State University. ... to national product manager, to helping develop, name and launch many of the most ...
(Date:5/4/2016)... York, NY (PRWEB) , ... May 04, 2016 ... ... has leveraged recent innovations in biotechnology to help treat hormonal and stress related ... loss, Nutrafol® has captured the hearts of key opinion leaders in the medical ...
Breaking Biology Technology: