Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Trees appear to respond slower to climate change than previously thought

03.08.2006
Genetic analysis of living spruce trees provides strong evidence for the presence of a tree refuge in Alaska during the height of the last glacial period (17,000 to 25,000 years ago), and suggests that trees cannot migrate in response to climate change as quickly as some scientists thought.

The DNA survey and analysis, led by researchers at the University of Illinois at Urbana-Champaign, will be posted online this week ahead of regular publication by the Proceedings of the National Academy of Sciences.

"White spruce (Picea glauca) is a dominant species in the boreal forests of North America," said Lynn L. Anderson, lead author and doctoral student. "In the face of global warming, we need to study how plant and animal populations have responded to climate change in the past, to better predict what will happen in the future."

In their study, the researchers analyzed chloroplast DNA from 24 spruce forests in Alaska and Canada. Because chloroplast DNA contains genes inherited from only one parent, there is no confusing genetic recombination to take into account.

"We found a significant pattern in the geographic distribution of the chloroplast DNA haplotypes (groups of individuals with similar sequences of base pairs of genetic material) that differentiates into two regions," Anderson said.

The chloroplast DNA, the researchers write, "offers compelling evidence that white spruce survived the last glacial maximum and probably some of the previous glacial episodes in Alaska. This survival must have been facilitated by the existence of favorable microhabitats … and by adaptations of these trees to harsh climate."

The DNA data help resolve an old controversy over the manner in which trees had migrated in response to past climate change, said Feng Sheng Hu, an ecologist at Illinois and corresponding author of the paper.

"One view is that trees were restricted to areas south of the continental ice sheets covering North America, and then migrated extremely rapidly as the climate grew warmer," Hu said. "The other view is that there was a refuge in the ice-free areas north of the ice sheets, and spruce trees expanded within those areas as the climate warmed. It now seems clear that a glacial refuge existed, and the trees advanced from at least two directions."

Based on the data, it also appears likely that the migration rate was lower than previously thought.

"Our results suggest that estimated rates of tree migration from fossil pollen records are too high and that the ability of trees to keep pace with global warming is more limited than previously thought," said Hu, who has studied plant responses to climate change for 15 years. "Additional analysis of fossil pollen in sediments, as well as DNA data from living trees, could help pin down the actual rate of tree movement over time."

The researchers' findings also illustrate the great resilience of white spruce – and perhaps other tree species – to climate change, and have important implications for the future.

For example, isolated populations of trees might persist in locally suitable habitats for long periods after regional climatic conditions have become unfavorable as a result of rapid global warming. This resilience might reduce the probability of species extinction and allow time for efforts at biodiversity conservation.

Or maybe not.

"Our study looked at the past, before humans had made any significant impact on climate," said Hu. "In the future, both human and natural disturbances will likely interact with climate change to reduce resilience and trigger larger ecological shifts."

The study "illustrates the power of using genetic techniques to answer paleoecological questions relevant to global change," said co-author Ken N. Paige, who has studied the genetic structure and dynamics of plant and animal populations for more than 20 years. "It's likely that more new insights can be gained by studying other plant and animal species with this approach."

James E. Kloeppel | EurekAlert!
Further information:
http://www.uiuc.edu

More articles from Ecology, The Environment and Conservation:

nachricht Bioinvasion on the rise
15.02.2017 | Universität Konstanz

nachricht Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

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: Breakthrough with a chain of gold atoms

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport

Im Focus: DNA repair: a new letter in the cell alphabet

Results reveal how discoveries may be hidden in scientific “blind spots”

Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...

Im Focus: Dresdner scientists print tomorrow’s world

The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.

The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...

Im Focus: Mimicking nature's cellular architectures via 3-D printing

Research offers new level of control over the structure of 3-D printed materials

Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...

Im Focus: Three Magnetic States for Each Hole

Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".

Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Booth and panel discussion – The Lindau Nobel Laureate Meetings at the AAAS 2017 Annual Meeting

13.02.2017 | Event News

Complex Loading versus Hidden Reserves

10.02.2017 | Event News

International Conference on Crystal Growth in Freiburg

09.02.2017 | Event News

 
Latest News

From rocks in Colorado, evidence of a 'chaotic solar system'

23.02.2017 | Physics and Astronomy

'Quartz' crystals at the Earth's core power its magnetic field

23.02.2017 | Earth Sciences

Antimicrobial substances identified in Komodo dragon blood

23.02.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>