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 Dune ecosystem modelling
23.06.2017 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Understanding animal social networks can aid wildlife conservation
23.06.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

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: Can we see monkeys from space? Emerging technologies to map biodiversity

An international team of scientists has proposed a new multi-disciplinary approach in which an array of new technologies will allow us to map biodiversity and the risks that wildlife is facing at the scale of whole landscapes. The findings are published in Nature Ecology and Evolution. This international research is led by the Kunming Institute of Zoology from China, University of East Anglia, University of Leicester and the Leibniz Institute for Zoo and Wildlife Research.

Using a combination of satellite and ground data, the team proposes that it is now possible to map biodiversity with an accuracy that has not been previously...

Im Focus: Climate satellite: Tracking methane with robust laser technology

Heatwaves in the Arctic, longer periods of vegetation in Europe, severe floods in West Africa – starting in 2021, scientists want to explore the emissions of the greenhouse gas methane with the German-French satellite MERLIN. This is made possible by a new robust laser system of the Fraunhofer Institute for Laser Technology ILT in Aachen, which achieves unprecedented measurement accuracy.

Methane is primarily the result of the decomposition of organic matter. The gas has a 25 times greater warming potential than carbon dioxide, but is not as...

Im Focus: How protons move through a fuel cell

Hydrogen is regarded as the energy source of the future: It is produced with solar power and can be used to generate heat and electricity in fuel cells. Empa researchers have now succeeded in decoding the movement of hydrogen ions in crystals – a key step towards more efficient energy conversion in the hydrogen industry of tomorrow.

As charge carriers, electrons and ions play the leading role in electrochemical energy storage devices and converters such as batteries and fuel cells. Proton...

Im Focus: A unique data centre for cosmological simulations

Scientists from the Excellence Cluster Universe at the Ludwig-Maximilians-Universität Munich have establised "Cosmowebportal", a unique data centre for cosmological simulations located at the Leibniz Supercomputing Centre (LRZ) of the Bavarian Academy of Sciences. The complete results of a series of large hydrodynamical cosmological simulations are available, with data volumes typically exceeding several hundred terabytes. Scientists worldwide can interactively explore these complex simulations via a web interface and directly access the results.

With current telescopes, scientists can observe our Universe’s galaxies and galaxy clusters and their distribution along an invisible cosmic web. From the...

Im Focus: Scientists develop molecular thermometer for contactless measurement using infrared light

Temperature measurements possible even on the smallest scale / Molecular ruby for use in material sciences, biology, and medicine

Chemists at Johannes Gutenberg University Mainz (JGU) in cooperation with researchers of the German Federal Institute for Materials Research and Testing (BAM)...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Plants are networkers

19.06.2017 | Event News

Digital Survival Training for Executives

13.06.2017 | Event News

Global Learning Council Summit 2017

13.06.2017 | Event News

 
Latest News

Quantum thermometer or optical refrigerator?

23.06.2017 | Physics and Astronomy

A 100-year-old physics problem has been solved at EPFL

23.06.2017 | Physics and Astronomy

Equipping form with function

23.06.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>