Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


New model revises estimates of terrestrial carbon dioxide uptake

Researchers at the University of Illinois have developed a new model of global carbon and nitrogen cycling that will fundamentally transform the understanding of how plants and soils interact with a changing atmosphere and climate.

The new model takes into account the role of nitrogen dynamics in influencing the response of terrestrial ecosystems to climate change and rising atmospheric carbon dioxide.

Current models used in the assessment reports of the Intergovernmental Panel on Climate Change do not account for nitrogen processing, and probably exaggerate the terrestrial ecosystem’s potential to slow atmospheric carbon dioxide rise, the researchers say. They will present their findings this week at the annual meeting of the American Geophysical Union in San Francisco.

In the face of global climate change, world leaders are in need of models that can reliably predict how land use and other human activities affect atmospheric carbon dioxide levels. Deforestation and the burning of coal and oil increase atmospheric carbon dioxide and contribute to global warming.

Growing plants take carbon dioxide from the air and store it as carbon in their tissues. This means that plant growth – especially that of trees – can help reduce the effects of rising carbon dioxide levels, which contribute to global warming.

Scientists have struggled for decades to build computer models that accurately predict how plants and soils will respond to rising carbon dioxide levels in the atmosphere.

In the 1990s, researchers reported that crop plants such as cotton or wheat are more productive when exposed to higher carbon dioxide levels. This “fertilization effect” increases CO2 uptake and was hailed by some as evidence that Earth’s forests also would take up more carbon dioxide as atmospheric levels increased.

But models of the carbon cycle have failed to take into account how nitrogen availability influences this equation on the global scale, said Atul Jain, a U. of I. professor of atmospheric sciences and principal investigator on the development of the new model.

Nitrogen is vital to carbon dioxide uptake in plants, and if the available nitrogen runs out, the plants won’t be able to make use of the added CO2, Jain said. In an agricultural landscape, nitrogen may be added as needed, he said, but forests have limited amounts of nitrogen in their soils.

The integrated science assessment model, originally developed by Jain, now has been expanded to take into account the net carbon impact of human activities and the role of rising atmospheric temperatures on the process of carbon uptake.

“Everything is integrated, not only the nitrogen, carbon and climate, but also we looked at land cover and land use changes,” Jain said. “A lot of deforestation and also aforestation and reforestation are going on, and that has a direct effect on the carbon dioxide release or absorption.”

The model accounts for different soil and vegetation types, the impact of climate and the inadvertent nitrogen deposition that results from fossil fuel and biomass burning.

Interestingly, warming temperatures in response to rising carbon dioxide levels could make more nitrogen available, said Xiaojuan Yang, a doctoral student in Jain’s lab. This factor must also be weighed in any calculation of net carbon dioxide load, she said.

“Previous modeling studies show that due to warming, the soil releases more carbon dioxide through increased decomposition,” she said. “But they are not considering the nitrogen effect. When the soil is releasing more CO2, at the same time more nitrogen is mineralized. This means that more nitrogen becomes available for plants to use.”

Increased nitrogen availability allows plants to uptake more carbon dioxide, a factor that mitigates, somewhat, the added burden of carbon dioxide in the atmosphere.

Even so, Jain said, the failure to look at the role of nitrogen in the terrestrial landscape means that countries may be overestimating the amount of carbon dioxide-uptake their forests provide.

Oak Ridge National Laboratory scientist Wilfred Post contributed to the research.

Diana Yates | University of Illinois
Further information:

More articles from Ecology, The Environment and Conservation:

nachricht Invasive Insects Cost the World Billions Per Year
04.10.2016 | University of Adelaide

nachricht Malaysia's unique freshwater mussels in danger
27.09.2016 | The University of Nottingham Malaysia Campus

All articles from Ecology, The Environment and Conservation >>>

The most recent press releases about innovation >>>

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

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

Greater Range and Longer Lifetime

26.10.2016 | Power and Electrical Engineering

VDI presents International Bionic Award of the Schauenburg Foundation

26.10.2016 | Awards Funding

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

More VideoLinks >>>