Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Alaska scientists find Arctic tundra yields surprising carbon loss

27.09.2004


Carbon loss from soils exceeds storage by plants

Institute of Arctic Biology (IAB) ecologists Donie Bret-Harte and Terry Chapin and colleagues working in northern Alaska discovered that tundra plants and soils respond in surprisingly opposite ways to conditions that simulate long-term climate warming.
Their findings are published in the September 23, 2004 edition of the leading science journal Nature and are featured in the journal’s News and Views section.


Bret-Harte, Chapin, lead author Michelle Mack of the University of Florida, Gainesville, and colleagues set out to investigate whether the commonly held assumption that a warming climate will lead to bigger plants that can store more carbon and thereby reduce atmospheric carbon dioxide was indeed a silver lining in the global warming cloud that some people had hoped for.

Apparently not.

"The broadest implication of this research is that climate warming could lead to a much greater release of carbon dioxide to the atmosphere and a greater positive feedback to further warming than we originally thought," Bret-Harte said.

In the experiment, conducted at IAB’s Toolik Field Station, researchers measured the amount of carbon and nitrogen in plants and soils from plots of tundra that have been continually fertilized since 1980 – a condition thought to simulate the increased nutrient availability expected as a result of a warmer climate. The plots are part of a 20-plus-year project by Terry Chapin of IAB, and Gus Shaver of The Ecosystems Center at the Marine Biological Laboratory in Massachusetts. "One of the greatest values of IAB’s Toolik Field Station is that it provides opportunities for long-term uninterrupted research in a pristine environment. We could never have gotten the results we did without such a long-term experiment," said Bret-Harte.

"The connection between fertilization and warming is that warmer temperatures should stimulate decomposition of dead plant material, releasing carbon to the atmosphere and nitrogen to plants. Nitrogen limits plant growth in most terrestrial ecosystems, said Bret-Harte" "What’s really surprising about this result is that we didn’t expect that this big loss of carbon from the soils would be stimulated by nitrogen alone. Everyone had assumed increased decomposition would be caused by increased temperatures, and the main effect of increased nitrogen would be to stimulate plant growth and store more carbon. We expected that fertilization by itself would lead to increased carbon storage." "Instead, nitrogen seems to stimulate decomposition and promote carbon dioxide release to the atmosphere from the soils," Bret-Harte said.

The researchers found that although the aboveground portion of tundra plants doubled their productivity under fertilization and, as expected, stored more carbon, the losses of carbon and nitrogen from the deep-soil layers was substantial and more than offset the increased carbon stored in the aboveground plants and plant litter.

Because more than one-third of the world’s soil carbon is stored in northern ecosystems – boreal forest and Arctic tundra – and is equivalent to two-thirds of the carbon found in the atmosphere, the loss of deep-soil carbon could mean an even greater increase in atmospheric carbon dioxide concentrations than is caused by fossil fuel burning. "The paradigm is that decomposers (microbes) are always limited by carbon availability and almost never limited by nitrogen availability, but this project suggests that we don’t understand decomposition as well as we thought we did. Better understanding of decomposition is necessary to be able to predict what will happen with climate warming in northern ecosystems."

Marie Gilbert | EurekAlert!
Further information:
http://www.uaf.edu

More articles from Ecology, The Environment and Conservation:

nachricht A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde

nachricht Value from wastewater
16.08.2017 | Hochschule Landshut

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

What the world's tiniest 'monster truck' reveals

23.08.2017 | Life Sciences

Treating arthritis with algae

23.08.2017 | Life Sciences

Witnessing turbulent motion in the atmosphere of a distant star

23.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>