Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New findings blow a decade of assumptions out of the water

12.01.2007
The Atlantic Ocean doesn't receive the mother lode of fixed nitrogen, the building block of life, after all. Instead, comparing fathom for fathom, the Pacific and Indian oceans experience twice the amount of nitrogen fixing as the Atlantic, say researchers in the Jan. 11 issue of Nature.

The title of an accompanying News and Views piece says it all, "Looking for N2 Fixation in all the Wrong Places."

It's important to have a global picture of where nitrogen fixation is occurring – that is where nitrogen gas is being converted into substances like nitrate that are usable by life – in order to understand the environmental controls on nitrogen fixation and its likely response to climate change in the past and in the future, says Curtis Deutsch, a University of Washington research assistant and lead author of a paper in the Jan. 11 issue of Nature. The new research, for example, indicates that the inventory of nitrogen in the oceans is likely to be less subject to major fluctuations than had been assumed.

Because it has been thought that nitrogen fixation is limited without enough iron, the conventional wisdom for the past decade dictated that the Atlantic Ocean would be the prime site for fixing nitrogen. That's because compared to the other low-latitude oceans, the Atlantic is peppered with iron-laden dust blowing off the African continent.

Winds can't carry such dust all the way across the Pacific Ocean because it is so vast. Iron may still be a limiting factor in nitrogen fixation, but if it is, then the Pacific and Indian oceans are getting iron from some source other than atmospheric dust, Deutsch says.

The new research also means places where nitrogen is being fixed by certain microorganisms are in close proximity to where it is being pulled back apart into its gaseous state by a different kind of micoorganism, he says.

Nitrogen gas, N2, is unusable by life. It has to be fixed, that is, latched onto other chemicals to form compounds such as nitrate, NO3. Only then can it be used to build amino acids and proteins essential to all life.

Eventually the fixed nitrogen is returned to its gaseous state, a process called denitrification. Scientists have known for several decades that denitrification occurs in the deep, low-oxygen waters of the Pacific and Indian oceans.

If the Atlantic was the site of a lot of nitrogen fixation, that would have put the two processes half a world away from each other. Scientists had estimated that, at those distances, it could take 1,000 years to re-balance the ocean's nitrogen cycle if large-scale changes were to occur in either nitrogen fixation or denitrification – if climate change altered ocean temperatures and the rates of the two processes, for instance.

The new findings show the processes are happening within a few hundred miles of each other so the balance could be reached within a decade, the authors estimate. Deutsch compares the old assumption to a house where the thermostat is many rooms away from a window that has swung open, letting in cold air. The house could get quite chilly before the draft reaches the thermostat and the furnace turns on. But if the thermostat is in the same room as the window, the furnace will turn on and even out the temperature much faster.

In his research Deutsch used a novel analysis of surface nutrients in the world's oceans that relied on several decades of existing large-scale data on nitrogen-to-phosphorous ratios, phosphorous also playing a major role in primary production. His work has been supported by a NASA Earth System Science Fellowship and the UW Program on Climate Change.

"There has been a great deal of controversy in the literature as to whether fixed nitrogen in the ocean remains constant with time or fluctuates widely," says Jorge Sarmiento, professor of geosciences at Princeton University and one of the co-authors. "This study is a major advance for those of us who have been arguing that it is relatively stable."

Sandra Hines | EurekAlert!
Further information:
http://www.washington.edu

More articles from Studies and Analyses:

nachricht Smart Data Transformation – Surfing the Big Wave
02.12.2016 | Fraunhofer-Institut für Angewandte Informationstechnik FIT

nachricht Climate change could outpace EPA Lake Champlain protections
18.11.2016 | University of Vermont

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Electron highway inside crystal

Physicists of the University of Würzburg have made an astonishing discovery in a specific type of topological insulators. The effect is due to the structure of the materials used. The researchers have now published their work in the journal Science.

Topological insulators are currently the hot topic in physics according to the newspaper Neue Zürcher Zeitung. Only a few weeks ago, their importance was...

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

Researchers identify potentially druggable mutant p53 proteins that promote cancer growth

09.12.2016 | Life Sciences

Scientists produce a new roadmap for guiding development & conservation in the Amazon

09.12.2016 | Ecology, The Environment and Conservation

Satellites, airport visibility readings shed light on troops' exposure to air pollution

09.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>