Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Russian Boreal Forests Undergoing Vegetation Change

29.03.2011
Russia's boreal forest – the largest continuous expanse of forest in the world, found in the country's cold northern regions – is undergoing an accelerating large-scale shift in vegetation types as a result of globally and regionally warming climate. That in turn is creating an even warmer climate in the region, according to a new study published in the journal Global Change Biology and highlighted in the April issue of Nature Climate Change.
The Great Russian forest, which includes much of Siberia, is the size of the contiguous United States. It has experienced significant documented warming over the last several decades. As a result, tree species that are more tolerant of warmer weather are advancing northward at an increasing rate as species that are less tolerant to a warmer climate are declining in number.

"We've identified that the boreal forest, particularly in Siberia, is converting from predominantly needle-shedding larch trees to evergreen conifers in response to warming climate," said the study's lead author, Jacquelyn Shuman, a post-doctoral research associate in environmental sciences in U.Va.'s Graduate School of Arts & Sciences. "This will promote additional warming and vegetation change, particularly in areas with low species diversity."

Larch trees drop their needles in the fall, allowing the vast snow-covered ground surface of winter to reflect sunlight and heat back into space. This helps keep the climate in the region very cold. But evergreen conifers, such as spruce and fur, retain their needles year round. These trees absorb sunlight, which causes ground-level heat retention. This creates ideal conditions for the proliferation of evergreens, to the detriment of the leaf-dropping larches. The result is a northward progression of evergreens and a farther-northward retreat by the larch forests.

"What we're seeing is a system kicking into overdrive," said co-author Hank Shugart, a U.Va. professor of environmental sciences. "Warming creates more warming."

The researchers used a climate model to assess what would happen if evergreens continued to expand their range farther north and larch species declined. The "positive feedback" cycle of warming promoting warming showed an increase of absorbed surface warming. The model takes into account detailed information about tree growth rates, and the results agree with actual field studies documenting changes in cone production and movement of evergreen treelines northward.

"Such changes in that vast region have the potential to affect areas outside of the region," Shuman noted.

The Russian boreal forest sits over a tremendous repository of carbon-rich soil frozen in the permafrost. As the forest changes in species distribution from larch to evergreens, warming of the ground surface would cause decomposition of the soil, releasing huge quantities of carbon dioxide into the atmosphere – possibly as much as 15 percent of the carbon dioxide currently in the atmosphere.
"This is not the scenario one would want to see," Shugart said. "It potentially would increase warming on a global scale."

The study is derived from Shuman's Ph.D. dissertation. Shugart served as her adviser. Their paper is co-authored by Thomas Liam O'Halloran, previously a doctoral student in environmental sciences at U.Va. and now a post-doctoral research associate at Oregon State University.

Shuman and Shugart recently received a $987,000, three-year grant from NASA to continue their studies.

Fariss Samarrai | EurekAlert!
Further information:
http://www.virginia.edu
http://www.virginia.edu/uvatoday/newsRelease.php?id=14554

Further reports about: SIBERIA Vegetation boreal forest carbon dioxide environmental science forests

More articles from Agricultural and Forestry Science:

nachricht Cascading use is also beneficial for wood
11.12.2017 | Technische Universität München

nachricht The future of crop engineering
08.12.2017 | Max-Planck-Institut für Biochemie

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

Im Focus: Successful Mechanical Testing of Nanowires

With innovative experiments, researchers at the Helmholtz-Zentrums Geesthacht and the Technical University Hamburg unravel why tiny metallic structures are extremely strong

Light-weight and simultaneously strong – porous metallic nanomaterials promise interesting applications as, for instance, for future aeroplanes with enhanced...

Im Focus: Virtual Reality for Bacteria

An interdisciplinary group of researchers interfaced individual bacteria with a computer to build a hybrid bio-digital circuit - Study published in Nature Communications

Scientists at the Institute of Science and Technology Austria (IST Austria) have managed to control the behavior of individual bacteria by connecting them to a...

Im Focus: A space-time sensor for light-matter interactions

Physicists in the Laboratory for Attosecond Physics (run jointly by LMU Munich and the Max Planck Institute for Quantum Optics) have developed an attosecond electron microscope that allows them to visualize the dispersion of light in time and space, and observe the motions of electrons in atoms.

The most basic of all physical interactions in nature is that between light and matter. This interaction takes place in attosecond times (i.e. billionths of a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Midwife and signpost for photons

11.12.2017 | Physics and Astronomy

How do megacities impact coastal seas? Searching for evidence in Chinese marginal seas

11.12.2017 | Earth Sciences

PhoxTroT: Optical Interconnect Technologies Revolutionized Data Centers and HPC Systems

11.12.2017 | Information Technology

VideoLinks
B2B-VideoLinks
More VideoLinks >>>