Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


ORNL-led study shows forests thrive with increased CO2 levels


Forest productivity may be significantly greater in an atmosphere enriched with carbon dioxide, according to findings released today that challenge recent reports that question the importance of carbon dioxide fertilization.

The study, performed by researchers at the Department of Energy’s Oak Ridge National Laboratory and 10 other institutions in the United States and Europe, revealed a strong relationship between productivity of forest plots in the current atmosphere and productivity in plots experimentally enriched with carbon dioxide.

"The median response indicated a 23 percent increase in productivity in the future atmosphere," said ORNL’s Rich Norby, lead author of the paper to be published Dec. 13 in the Proceedings of the National Academy of Sciences. "What was especially surprising to the research team was the consistency of the response across a wide range of productivity."

Researchers analyzed data from four experiments in which young forest stands were exposed for multiple years to an atmosphere with a carbon dioxide concentration predicted to occur in the middle of this century. The experiments were conducted in a deciduous forest in Tennessee, a pine forest in North Carolina, a young hardwood stand in Wisconsin and a high-productivity poplar plantation in Italy.

The team calculated net primary productivity - the annual fixation of carbon by green plants into organic matter - for each of the sites from data on wood, leaf and fine-root production. The results proved surprising.

"When we got together to analyze these data, we expected to spend our time explaining the differences between sites," said Norby, a member of ORNL’s Environmental Sciences Division. "We were really surprised and excited when all of the data fell neatly onto a single line."

More detailed analysis of the data revealed the mechanisms of the forest productivity response. In forest stands with a relatively low amount of leaf area, the response to elevated carbon dioxide levels was explained by increased absorption of light. With greater leaf area, however, the response was an increased efficiency of conversion of light energy to organic matter. In separating the overall response into leaf area and light-use efficiency, the analysis meshes well with broader scale analyses based on satellite imagery, Norby said.

Norby notes that this analysis will be especially valuable as a benchmark to evaluate predictions of ecosystem and global models.

"Climate change predictions are dependent on assumptions about the interaction between the biosphere and atmosphere," Norby said. "However, the contribution of carbon dioxide fertilization to the future carbon global carbon cycle has been uncertain and the models are poorly constrained by experimental data. The close agreement of the productivity predictions of models with the new experimental data should add confidence to overall model results."

Norby cautioned against viewing these results as a reason to ignore the steadily increasing amount of carbon dioxide in the atmosphere.

"Although carbon dioxide fertilization of forests might slow the rate of increase of atmospheric carbon dioxide, a 23 percent increase in productivity is insufficient to stabilize the concentration in the atmosphere," he said. "The increase in productivity demonstrated in these experiments will most likely be tempered by the stresses of climate warming, ozone pollution or insufficient nitrogen supply. In addition, some of the increased organic matter entering the forest is not sequestered in wood but is rapidly returned to the atmosphere. Understanding the controls on carbon processing by ecosystems remains a priority research challenge."

This study, funded primarily the DOE’s Office of Science, Biological and Environmental Research and the National Science Foundation, reinforces earlier findings and challenges reports that question the importance of carbon dioxide fertilization based on observations of a few trees.

UT-Battelle manages Oak Ridge National Laboratory for the Department of Energy.

Ron Walli | EurekAlert!
Further information:

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

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

Im Focus: Locomotion control with photopigments

Researchers from Göttingen University discover additional function of opsins

Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...

Im Focus: Surveying the Arctic: Tracking down carbon particles

Researchers embark on aerial campaign over Northeast Greenland

On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...

Im Focus: Unique Insights into the Antarctic Ice Shelf System

Data collected on ocean-ice interactions in the little-researched regions of the far south

The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...

Im Focus: ILA 2018: Laser alternative to hexavalent chromium coating

At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.

When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...

Im Focus: Radar for navigation support from autonomous flying drones

At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.

Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...

All Focus news of the innovation-report >>>



Industry & Economy
Event News

Ultrafast Wireless and Chip Design at the DATE Conference in Dresden

16.03.2018 | Event News

International Tinnitus Conference of the Tinnitus Research Initiative in Regensburg

13.03.2018 | Event News

International Virtual Reality Conference “IEEE VR 2018” comes to Reutlingen, Germany

08.03.2018 | Event News

Latest News

Wandering greenhouse gas

16.03.2018 | Earth Sciences

'Frequency combs' ID chemicals within the mid-infrared spectral region

16.03.2018 | Physics and Astronomy

Biologists unravel another mystery of what makes DNA go 'loopy'

16.03.2018 | Life Sciences

Science & Research
Overview of more VideoLinks >>>