In dark, rich soils on every continent, microbes dealing with the effects of climate change aren't accelerating global warming the way scientists had predicted, a study by researchers at the University of California at Irvine, Colorado State University and Yale University shows.
Results of the study appear in a paper published on-line this week in the journal Nature Geoscience. The work was supported by the National Science Foundation (NSF) and U.S. Department of Energy.
"Microbes continually surprise us in the diverse ways they respond to environmental conditions," said Saran Twombly, program director in NSF's Division of Environmental Biology, which funded the research along with NSF's Advancing Theory in Biology program, part of the Directorate for Biological Sciences Office of Emerging Frontiers.
"Microbes play a central role in ecological processes," said Twombly, "and their responses change our understanding of natural communities in fundamental ways."
Conventional scientific wisdom holds that even a few degrees of human-caused climate warming will shift fungi and bacteria that consume soil-based carbon into overdrive, and that their growth will accelerate the release of carbon dioxide into the atmosphere.
But a research team led by ecologist Steve Allison of UC Irvine took a closer look, and found something different.
While microbial soil decomposition, and resulting carbon dioxide emissions, increase initially, microbes eventually overheat and grow more slowly.
As their numbers decline, they release decreasing amounts of climate-warming greenhouse gases.
"Microbes are the engines that drive carbon cycling in soils," said Allison.
"In a balanced environment, plants store carbon in the soil and microbes use that carbon to grow. Enzymes produced by microbes convert soil carbon into atmospheric carbon dioxide."
A previous study by Mark Bradford of Yale and Matthew Wallenstein of Colorado State found that microbes became less efficient at decomposing soil carbon after several years of experimental warming.
They asked Allison to develop a computer model to test how adaptation of microbes to climate change might affect the carbon cycle.
"The issue we have in predicting whether soil carbon loss will accelerate climate warming is that the microbial processes causing this loss are poorly understood," said Bradford. "More research in this area will help reduce uncertainties in climate prediction."
In the resulting computer model, microbes became less efficient at converting their carbon food source into biomass as climate warmed.
In short, the microbes were not well adapted to a warmer climate. As their growth slowed, so did enzyme production.
"When we developed a model based on the actual biology of soil microbes, we found that soil carbon may not be lost to the atmosphere as the climate warms," Allison said. "Conventional ecosystem models that didn't include enzymes did not make the same predictions."
The next steps include studying more microbes and more ecosystems.
Microbes from a Massachusetts forest inspired this study, then Allison began collecting soil samples from California, Alaska, Maine and Costa Rica.
"Nearly one-third of all soil-based carbon is sequestered in permafrost or Arctic regions, which might respond differently to warming," said Wallenstein, who is researching sites in Greenland and Alaska.
"We need to develop more models to include microbe diversity," Allison said. "But the general principle that's important in our model is the decline of carbon dioxide production after an initial increase."
Cheryl Dybas | EurekAlert!
Novel method for investigating pore geometry in rocks
18.06.2018 | Kyushu University, I2CNER
Decades of satellite monitoring reveal Antarctic ice loss
14.06.2018 | University of Maryland
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
19.06.2018 | Physics and Astronomy
19.06.2018 | Life Sciences
19.06.2018 | Physics and Astronomy