Researchers at the University of Illinois at Urbana-Champaign and the University of Bristol Cabot Institute published their findings in the journal Global Change Biology. The findings will be a part of the upcoming Fifth Assessment Report from the Intergovernmental Panel on Climate Change.
“One nutrient can make a huge impact on the carbon cycle and net emissions of the greenhouse gas carbon dioxide,” said study leader Atul Jain, a professor of atmospheric sciences at the U. of I. “We know that climate is changing, but the question is how much? To understand that, we have to understand interactive feedback processes – the interactions of climate with the land, but also interactions between nutrients within the land.”
The carbon cycle is a balance of carbon emissions into the atmosphere and absorption by oceans and terrestrial ecosystems. Carbon is absorbed by plants during photosynthesis and by the oceans through sea-air gas exchange. On the other side of the cycle, carbon is released by burning fossil fuels and by changes in land use – deforestation to expand croplands, for example. While fossil fuel emissions are well-known, there are large uncertainties in estimated emissions from land use change.
“When humans disturb the land, the carbon stored in the plants and the soil goes back into the atmosphere,” Jain said. “But when plants regrow, they absorb carbon through photosynthesis. Absorption or release of carbon can be enhanced or dampened depending on environmental conditions, such as climate and nutrient availability.”
Nitrogen is an essential mineral nutrient for plants, which means that plants need it to grow and thrive. In nontropical regions especially, plant regrowth – and therefore carbon assimilation by plants – is limited by nitrogen availability.
“Most models used to estimate global land use change emissions to date do not have the capability to model this nitrogen limitation on plant regrowth following land use change,” said Prasanth Meiyappan, a graduate student who is a co-author of the study. “This means, for example, they overestimate regrowth and they underestimate net emissions from the harvest-regrowth cycle in temperate forest plantations.”
Jain’s team, in collaboration with Joanna House, a researcher at the University of Bristol’s Cabot Institute, concluded that by not accounting for nitrogen as a limiting nutrient for plant growth, other models might have underestimated the 1990s carbon emissions from land use change by 70 percent in nontropical regions and by 40 percent globally.“This gross underestimation has great implications for international policy,” House said. “If emissions from land-use change are higher than we thought, or the land sink (regrowth) is more limited, then future emissions cuts would have to be deeper to meet the same mitigation targets.”
Next, the researchers are investigating the impacts of other nutrients, such as phosphorus, on the carbon cycle. They also are estimating the carbon stored in the soil, and how much is released or absorbed when the soil is perturbed.
“Soil has great potential to sequester carbon,” Jain said. “The question is, how much that’s being released is being sequestered in the soil? We have to understand how human behavior is changing our environment and interacting with our ecosystems.”
The National Aeronautics and Space Administration, the U.S. Department of Energy and the UK Leverhulme Trust supported this work.
Liz Ahlberg | EurekAlert!
Conservationists are sounding the alarm: parrots much more threatened than assumed
15.09.2017 | Justus-Liebig-Universität Gießen
A new indicator for marine ecosystem changes: the diatom/dinoflagellate index
21.08.2017 | Leibniz-Institut für Ostseeforschung Warnemünde
Whispering gallery mode (WGM) resonators are used to make tiny micro-lasers, sensors, switches, routers and other devices. These tiny structures rely on a...
Using ultrafast flashes of laser and x-ray radiation, scientists at the Max Planck Institute of Quantum Optics (Garching, Germany) took snapshots of the briefest electron motion inside a solid material to date. The electron motion lasted only 750 billionths of the billionth of a second before it fainted, setting a new record of human capability to capture ultrafast processes inside solids!
When x-rays shine onto solid materials or large molecules, an electron is pushed away from its original place near the nucleus of the atom, leaving a hole...
For the first time, physicists have successfully imaged spiral magnetic ordering in a multiferroic material. These materials are considered highly promising candidates for future data storage media. The researchers were able to prove their findings using unique quantum sensors that were developed at Basel University and that can analyze electromagnetic fields on the nanometer scale. The results – obtained by scientists from the University of Basel’s Department of Physics, the Swiss Nanoscience Institute, the University of Montpellier and several laboratories from University Paris-Saclay – were recently published in the journal Nature.
Multiferroics are materials that simultaneously react to electric and magnetic fields. These two properties are rarely found together, and their combined...
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems Holding GmbH about commercial use of a multi-well tissue plate for automated and reliable tissue engineering & drug testing.
MBM ScienceBridge GmbH successfully negotiated a license agreement between University Medical Center Göttingen (UMG) and the biotech company Tissue Systems...
Pathogenic bacteria are becoming resistant to common antibiotics to an ever increasing degree. One of the most difficult germs is Pseudomonas aeruginosa, a...
19.09.2017 | Event News
12.09.2017 | Event News
06.09.2017 | Event News
20.09.2017 | Life Sciences
20.09.2017 | Power and Electrical Engineering
20.09.2017 | Physics and Astronomy