Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Standing trees better than burning ones for carbon neutrality

01.06.2012
The search for alternatives to fossil fuels has prompted growing interest in the use of wood, harvested directly from forests, as a carbon-neutral energy source.
But a new study by researchers at Duke and Oregon State universities finds that leaving forests intact so they can continue to store carbon dioxide and keep it from re-entering the atmosphere will do more to curb climate change over the next century than cutting and burning their wood as fuel.

"Substituting woody bioenergy for fossil fuels isn't an effective method for climate change mitigation," said Stephen R. Mitchell, a research scientist at Duke's Nicholas School of the Environment. Wood stores only about half the amount of carbon-created energy as an equivalent amount of fossil fuels, he explained, so you have to burn more of it to produce as much energy.

"In most cases, it would take more than 100 years for the amount of energy substituted to equal the amount of carbon storage achieved if we just let the forests grow and not harvest them at all," he said.

Mitchell is lead author of the study published in the peer-reviewed journal Global Change Biology Bioenergy. Mark E. Harmon and Kari E. O'Connell of Oregon State University co-authored the study.

Using an ecosystem simulation model developed at Oregon State, the team calculated how long it would take to repay the carbon debt – the net reduction in carbon storage – incurred by harvesting forests for wood energy under a variety of different scenarios.

Their model accounted for a broad range of harvesting practices, ecosystem characteristics and land-use histories. It also took into account varying bioenergy conversion efficiencies, which measure the amount of energy that woody biomass gives off using different energy-generating technologies.

"Few of our combinations achieved carbon sequestration parity in less than 100 years, even when we set the bioenergy conversion factor at near-maximal levels," Harmon said. Because wood stores less carbon-created energy than fossil fuels, you have to harvest, transport and burn more of it to produce as much energy. This extra activity produces additional carbon emissions.

"These emissions must be offset if forest bioenergy is to be used without adding to atmospheric carbon dioxide concentrations in the near-term," he said.

Performing partial harvests at a medium to low frequency – every 50 to 100 years or so – could be an effective strategy, O'Connell noted, but would generate less bioenergy.

"It's a Catch-22," she said. "Less intensive methods of harvesting release fewer emissions but yield less energy. The most intensive methods, such as clear-cutting, produce more energy but also release more carbon back into the atmosphere, prolonging the time required to achieve carbon sequestration parity."

Given current economic realities and the increasing worldwide demand for forest products and land for agriculture, it's unlikely that many forests will be managed in coming years solely for carbon storage, Mitchell said, but that makes it all the more critical that scientists, resource managers and policymakers work together to maximize the carbon storage potential of the remaining stands.

"The take-home message of our study is that managing forests for maximal carbon storage can yield appreciable, and highly predictable, carbon mitigation benefits within the coming century," Mitchell said. "Harvesting forests for bioenergy production would require such a long time scale to yield net benefits that it is unlikely to be an effective avenue for climate-change mitigation."

The research was funded by a NASA New Investigator Program grant to Kari O'Connell, by the H.J. Andrews Long-term Ecological Research Program, and by the Kay and Ward Richardson Endowment.

Tim Lucas | EurekAlert!
Further information:
http://www.duke.edu

More articles from Ecology, The Environment and Conservation:

nachricht Upcycling 'fast fashion' to reduce waste and pollution
03.04.2017 | American Chemical Society

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | 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: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

Bare bones: Making bones transparent

27.04.2017 | Life Sciences

Study offers new theoretical approach to describing non-equilibrium phase transitions

27.04.2017 | Physics and Astronomy

From volcano's slope, NASA instrument looks sky high and to the future

27.04.2017 | Earth Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>