Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Decomposing logs show local factors undervalued in climate change predictions

03.06.2014

A new Yale-led study challenges the long-held assumption that climate is the primary driver of how quickly organic matter decomposes in different regions, a key piece of information used in formulating climate models.

In a long-term analysis conducted across several sites in the eastern United States, a team of researchers found that local factors — from levels of fungal colonization to the specific physical locations of the wood — play a far greater role than climate in wood decomposition rates and the subsequent impacts on regional carbon cycling.


Researchers distributed 160 blocks of pine tree wood across five sub-regions of temperate forest in the eastern United States to determine the affect of local factors on carbon cycling.

Because decomposition of organic matter strongly influences the storage of carbon, or its release into the atmosphere, it is a major factor in potential changes to the climate.

The findings underscore a key limitation of using aggregated data across wide geographic areas to predict future climate change, said Mark A. Bradford, an assistant professor of terrestrial ecosystem ecology at the Yale School of Forestry & Environmental Studies (F&ES) and lead author of the study published in the journal Nature Climate Change.

They also suggest that better identifying and measuring such hyper-local ecological factors could significantly improve the effectiveness of climate change projections, he adds.

“We’re reaching the wrong conclusion about the major controls on decomposition because of the way we’ve traditionally collected and looked at our data,” Bradford said. “That in turn will weaken the effectiveness of climate prediction.”

It has long been thought that climate is the predominant factor controlling decomposition, mainly because warmer temperatures increase the activity levels of the “decomposer” organisms, such as microbes, that break down dead organic matter.

While scientific studies have revealed the critical importance of climate and temperature in determining decomposition rates across regional and global scales, the findings are often based on the mean response of decomposition across large areas.

According to Bradford, the use of mean responses can mask the local-scale information, such as the abundance of soil fungi and animals, which may be more important in governing the release of terrestrial carbon.

To better assess the importance of those local effects, the researchers distributed 160 blocks of pine tree wood across five sub-regions of temperate forest in the eastern United States — from Connecticut to northern Florida — and then monitored the decay that occurred over 13 months.

They selected similar forest types in order to focus on major differences in the effect of climate across the regional gradient. (The average annual temperature in southern New England is about 11 degrees Celsius cooler than Florida.) But within each of the five sub-regions they placed the wood blocks in different types of terrain to evaluate the effects of local versus regional factors on decomposition and capture the variability found in forest environments.

“Most people would try to make sure everything was as standard as possible,” Bradford said. “We said, ‘Well, let’s generate as much variation as possible.’ So we put some blocks on south-facing slopes, where they would be warmer in the summer, and others on north-facing slopes where it’s colder. We put some on top of ridges and others next to streams where it was wetter.”

After 13 months, they measured how much carbon had been lost, whether absorbed by the microbes growing on the wood or directly into the atmosphere as carbon dioxide.

According to their analysis, local-scale factors explained about three-quarters of the variation in wood decomposition, while climate explained only about one-quarter, contrary to the expectation that climate should be the predominant control.

Since those local factors likely are the primary drivers of decomposition rates, Bradford said, they should be better documented and integrated into climate models.

“The [climate] modelers know that they can only produce models based on the data sets that we give them,” he said. “So the message for field ecologists like me is to go out and get much richer data sets with much more information. We shouldn’t aggregate away information. We should make measurements at those local scales to capture all of the importance processes that affect ecosystem functioning.

“Then the modelers will have far richer data sets to test their models against and see if they work,” he adds.

The study was a collaboration among researchers from Yale; State University of New York-Buffalo; the Institute of Microbiology, Academy of Sciences of the Czech Republic; the U.S. National Center for Atmospheric Research; Columbia University; and the University of Central Florida.

Co-authors of the study, “Climate fails to predict wood decomposition at regional scales,” include Thomas W. Crowther, Daniel S. Maynard, and Emily E. Oldfield of the Yale School of Forestry & Environmental Studies.

The research was funded by the National Science Foundation’s Division of Environmental Biology and the Yale Climate & Energy Institute.

To read the complete article, visit: http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate2251.html

Kevin Dennehy | Eurek Alert!
Further information:
http://www.yale.edu

Further reports about: Environmental Forestry blocks decomposition ecosystem effects microbes terrestrial

More articles from Earth Sciences:

nachricht Errant Galileo satellites will be used for research on Einstein’s general theory of relativity
31.08.2015 | Zentrum für angewandte Raumfahrttechnologie und Mikrogravitation (ZARM)

nachricht Time travel into the past of marginal seas: IOW expedition explores Canadian coastal waters
31.08.2015 | Leibniz-Institut für Ostseeforschung Warnemünde

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Increasingly severe disturbances weaken world's temperate forests

Longer, more severe, and hotter droughts and a myriad of other threats, including diseases and more extensive and severe wildfires, are threatening to transform some of the world's temperate forests, a new study published in Science has found. Without informed management, some forests could convert to shrublands or grasslands within the coming decades.

"While we have been trying to manage for resilience of 20th century conditions, we realize now that we must prepare for transformations and attempt to ease...

Im Focus: OU astrophysicist and collaborators find supermassive black holes in quasar nearest Earth

A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.

The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...

Im Focus: What would a tsunami in the Mediterranean look like?

A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).

Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...

Im Focus: Self-healing landscape: landslides after earthquake

In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.

These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...

Im Focus: FIC Proteins Send Bacteria Into Hibernation

Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.

For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Networking conference in Heidelberg for outstanding mathematicians and computer scientists

20.08.2015 | Event News

Scientists meet in Münster for the world’s largest Chitin und Chitosan Conference

20.08.2015 | Event News

Large agribusiness management strategies

19.08.2015 | Event News

 
Latest News

Production research by Fraunhofer IAO honored with three awards at the ICPR 2015

31.08.2015 | Awards Funding

Single-Crystal Phosphors Suitable for Ultra-Bright, High-Power White Light Sources

31.08.2015 | Materials Sciences

Manchester Team Reveal New, Stable 2D Materials

31.08.2015 | Materials Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>