There may be valid reasons to thin forests – such as restoration of forest structure or health, wildlife enhancement or public safety – but increased carbon sequestration is not one of them, scientists say.
In research just published in Frontiers in Ecology and the Environment, Oregon State University scientists conclude that even in fire-prone forests, it’s necessary to treat about 10 locations to influence fire behavior in one. There are high carbon losses associated with fuel treatment and only modest savings in reducing the severity of fire, they found.
“Some researchers have suggested that various levels of tree removal are consistent with efforts to sequester carbon in forest biomass, and reduce atmospheric carbon dioxide levels,” said John Campbell, an OSU research associate in the Department of Forest Ecosystems and Society. “That may make common sense, but it’s based on unrealistic assumptions and not supported by the science.”
A century of fire suppression in many forests across the West has created a wide range of problems, including over-crowded forests, increased problems with insect and pathogen attack, greater risk of catastrophic fire and declining forest health.
Forest thinning and fuel reduction may help address some of those issues, and some believe that it would also help prevent more carbon release to the atmosphere if it successfully reduced wildfire.
“There is no doubt you can change fire behavior by managing fuels and there may be other reasons to do it,” said Mark Harmon, holder of the Richardson Chair in Forest Science at OSU. “But the carbon does not just disappear, even if it’s used for wood products or other purposes. We have to be honest about the carbon cost and consider it along with the other reasons for this type of forest management.”
Even if wood removed by thinning is used for biofuels it will not eliminate the concern. Previous studies at OSU have indicated that, in most of western Oregon, use of wood for biofuels will result in a net loss of carbon sequestration for at least 100 years, and probably much longer.
In the new analysis, researchers analyzed the effect of fuel treatments on wildfire and carbon stocks in several scenarios, including a single forest patch or disturbance, an entire forest landscape and multiple disturbances.
One key finding was that even a low-severity fire released 70 percent as much carbon as did a high-severity fire that killed most trees. The majority of carbon emissions result from combustion of surface fuels, which occur in any type of fire.
The researchers also said that the basic principles in these evaluations would apply to a wide range of forest types and conditions, and are not specific to just a few locations.
“People want to believe that every situation is different, but in fact the basic relationships are consistent,” Campbell said. “We may want to do fuel reduction across much of the West, these are real concerns. But if so we’ll have to accept that it will likely increase carbon emissions.”
About the OSU College of Forestry: For a century, the College of Forestry has been a world class center of teaching, learning and research. It offers graduate and undergraduate degree programs in sustaining ecosystems, managing forests and manufacturing wood products; conducts basic and applied research on the nature and use of forests; and operates 14,000 acres of college forests.
Mark Harmon | EurekAlert!
Road access for all would be costly, but not so much for the climate
10.07.2020 | Potsdam-Institut für Klimafolgenforschung
Innovative grilling technique improves air quality
01.07.2020 | Fraunhofer Institute for Building Physics IBP
New insight into the spin behavior in an exotic state of matter puts us closer to next-generation spintronic devices
Aside from the deep understanding of the natural world that quantum physics theory offers, scientists worldwide are working tirelessly to bring forth a...
Kiel physics team observed extremely fast electronic changes in real time in a special material class
In physics, they are currently the subject of intensive research; in electronics, they could enable completely new functions. So-called topological materials...
Solar cells based on perovskite compounds could soon make electricity generation from sunlight even more efficient and cheaper. The laboratory efficiency of these perovskite solar cells already exceeds that of the well-known silicon solar cells. An international team led by Stefan Weber from the Max Planck Institute for Polymer Research (MPI-P) in Mainz has found microscopic structures in perovskite crystals that can guide the charge transport in the solar cell. Clever alignment of these "electron highways" could make perovskite solar cells even more powerful.
Solar cells convert sunlight into electricity. During this process, the electrons of the material inside the cell absorb the energy of the light....
Empa researchers have succeeded in applying aerogels to microelectronics: Aerogels based on cellulose nanofibers can effectively shield electromagnetic radiation over a wide frequency range – and they are unrivalled in terms of weight.
Electric motors and electronic devices generate electromagnetic fields that sometimes have to be shielded in order not to affect neighboring electronic...
A promising operating mode for the plasma of a future power plant has been developed at the ASDEX Upgrade fusion device at Max Planck Institute for Plasma...
07.07.2020 | Event News
02.07.2020 | Event News
19.05.2020 | Event News
10.07.2020 | Life Sciences
10.07.2020 | Materials Sciences
10.07.2020 | Life Sciences