Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

More carbon dioxide may help some trees weather ice storms

17.08.2006
The increased levels of carbon dioxide in the atmosphere predicted for later this century may reduce the damage that future ice storms will cause to commercially important loblolly pine trees, according to a new study.

Researchers working at a Duke University outdoor test facility found that loblolly pines growing under carbon-dioxide levels mimicking those predicted for the year 2050 -- roughly one and a half times today's levels -- fared somewhat better during and after a major ice storm that hit the area than did loblollies growing under current concentrations of the gas.

The results came as a surprise, the researchers said.

"Before the storm, I was absolutely certain the pines would be more susceptible to ice damage under elevated concentrations of carbon dioxide," said Ram Oren, an ecology professor at Duke's Nicholas School of the Environment and Earth Sciences who directs the test site and participated in the study.

"My impressions were absolutely wrong," he said. "Instead of increasing the sensitivity to ice-storm damage, carbon dioxide decreased the sensitivity."

The researchers reported the findings August 8, 2006, in the Journal of Geophysical Research. The first author of the report is Heather McCarthy, a Nicholas School graduate student. The study was funded by the U.S. Department of Energy and the Forest Service.

Scientists predict that concentrations of carbon dioxide in the air will continue to rise as people continue to burn fossil fuels and clear land for agriculture, and that this rise will help drive global warming. Carbon dioxide is widely thought to play a major role in global warming because it traps solar heat in the atmosphere, much as the glass in a greenhouse traps heat.

At the Free-Air Carbon Dioxide Enrichment (FACE) experiment, located in the Duke Forest research reserve, researchers since 1994 have been studying how this predicted extra gas would affect a typical Southeastern forest ecosystem. At the site, a computer-controlled network of pipes and valves feeds carbon dioxide from elevated towers to trees growing in three different open-air plots. Three other identical "control" plots receive no additional carbon dioxide.

Following the ice storm, which hit in December 2002, the researchers collected and measured ice-felled tree parts in the study area. They found "fewer damaged trees" and "less damage per tree" in plots with elevated carbon-dioxide concentrations, according to their journal report.

"These results suggest that forests may suffer less damage during each ice storm event of similar severity in a future with higher atmospheric carbon dioxide," the researchers said.

Overall, the researchers found that about 20 percent of the trees in plots "treated" with carbon dioxide were damaged, compared with 29 percent of the trees in control plots. Tree tops broken off by the ice in the treated plots also tended to be shorter in length.

In the growing season following the storm, trees in the treated plots recovered better since they had suffered less damage, the scientists found.

The scientists cautioned, however, that they were not able to identify the actual mechanisms that helped to protect the trees grown under elevated carbon-dioxide conditions. "We just couldn't tease out anything obvious," McCarthy said.

They were able to rule out one potentially obvious explanation.

Previous studies at FACE had suggested that new wood grown under elevated carbon-dioxide levels is less dense than normal, so it might be expected that the tops of trees grown under these conditions would be more fragile, Oren and McCarthy said.

But broken-off tree tops collected after the storm from under damaged trees in the treated plots turned out to have normal wood densities, they said. That finding counters the notion that structural weaknesses where tops had broken off are tied to density differences.

As one open possibility, Oren suggested that higher carbon-dioxide levels may have induced the trees to reshape their tops, making them thicker and thus better able to withstand the ice load without breaking.

Whether or not this is the answer will be revealed only when all of the trees are harvested and their individual structures studied in detail, he added.

The test results may hold meaning for the future of commercial pine forests in the Southeast, Oren said. If future studies confirm that loblolly pines growing under higher carbon-dioxide concentrations are better able to resist ice damage, then this might "generate future scenarios in which loblollies could actually migrate farther north," he said.

Ice storms now are major barriers to the northward migration of loblollies, which are susceptible to cold temperatures and ice damage. But according to the results of this study, Oren said, climate changes under global warming would tend to favor the spread of such fast-growing trees.

Monte Basgall | EurekAlert!
Further information:
http://www.duke.edu

More articles from Earth Sciences:

nachricht A promising target in the quest for a 1-million-year-old Antarctic ice core
24.05.2018 | University of Washington

nachricht Tropical Peat Swamps: Restoration of Endangered Carbon Reservoirs
24.05.2018 | Leibniz-Zentrum für Marine Tropenforschung (ZMT)

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

 
Latest News

In focus: Climate adapted plants

25.05.2018 | Event News

Flow probes from the 3D printer

25.05.2018 | Machine Engineering

Less is more? Gene switch for healthy aging found

25.05.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>