Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

For the sake of land and climate, coaxing soil to soak up carbon

02.04.2004


Promising results of soil treatments to sequester carbon lead to field tests



In a novel approach to stalling global warming while reinvigorating nutrient-depleted farmland, chemists have found they can promote soil’s natural ability to soak up greenhouse-gas carbon dioxide from the surrounding air.

Experiments led by Jim Amonette at the Department of Energy’s Pacific Northwest National Laboratory in Richland, Wash., and reported today at the American Chemical Society national meeting, show that maintaining a proper alkalinity plus frequent wetting and drying cycles can coax soil to retain more carbon.


"Globally, soils contain four times as much carbon as the atmosphere, and half of the soil carbon is in the form of organic matter," said Amonette, a PNNL senior research scientist. Until about 30 years ago, soil tillage released more carbon dioxide to the atmosphere than burning of fossil fuels. Some agricultural soils have lost a third of their carbon from tillage.

"These carbon-depleted soils are a tremendous potential reservoir for carbon that can help slow the increase in atmospheric carbon dioxide," Amonette said. "The amount of carbon added to soil in a year is incredible. Today, 99 percent of it comes out the top as carbon dioxide. If we can increase the fraction that is retained in soil by even a small amount, it will make a huge difference."

Amonette’s experiments promoted the activity of tyrosinase, a common enzyme that catalyzes soil’s natural "humification" process. This process involves the gradual incorporation of carbon from dead plants and microbes into stable organic matter called humus, which is responsible for the dark color in many soils. Tyrosinase increases the reaction rate between oxygen and humus precursors, such as phenols and hydroxybenzoic acids, to form quinones. The quinones react with amino acids released by soil microbes to form complex, durable molecules called humic polymers.

"Because humic polymers are less easily degraded by microbes than the precursor molecules, they survive to diffuse into small pores in soil aggregates where they are stabilized for decades, if not centuries," Amonette said.

The humification rate depends on many factors: enzyme stability, moisture, alkalinity, oxygen availability, microbial population and the physical properties of different soils. Amonette’s experiments were designed to weigh the importance of these many factors and to learn ways they might be manipulated to increase humification.

In the lab, Amonette assembled 72 elaborate plastic-tube configurations he likens to "those Russian nesting dolls," matrioshkas. The tubes allowed Amonette to control individual moisture levels and oxygen availability. Each soil sample was placed between the inner and outer walls of water-tight but gas-porous concentric cylinders. These were placed inside yet a larger "chimney" tube to control the humidity as well as the type of gas and its flow rate.

Amonette was particularly interested in identifying soil components and soil additives that might improve tyrosinase’s natural ability to promote humification. He found that an alkaline, porous material called "fly ash," a byproduct of coal combustion, "speeds up the normal humification process by promoting the reaction of the quinones with the amino acids and providing small pores to protect humic polymers," he said. "Frequent cycles of wetting and drying appear to be important, too, for fostering a rich microbial community that supplies many of the humic precursors and for aiding the formation of soil aggregates."

Amonette is eager to put his results to the test where it matters most--in the field. He will get his wish in May, when he travels to a field outside of Charleston, S.C. There, he and collaborators from the U.S. Forest Service and Oak Ridge National Laboratory will plant 72 pots containing various controlled mixtures of soil and catalysts.


###
PNNL is a DOE Office of Science laboratory that solves complex problems in energy, national security, the environment and life sciences by advancing the understanding of physics, chemistry, biology and computation. PNNL employs 3,800, has a $600 million annual budget, and has been managed by Ohio-based Battelle since the lab’s inception in 1965.

Bill Cannon | PNNL
Further information:
http://www.pnl.gov/news/2004/04-25.htm

More articles from Ecology, The Environment and Conservation:

nachricht Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung

nachricht International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)

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: A Challenging European Research Project to Develop New Tiny Microscopes

The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.

To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...

Im Focus: Giant Magnetic Fields in the Universe

Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.

The results will be published on March 22 in the journal „Astronomy & Astrophysics“.

Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...

Im Focus: Tracing down linear ubiquitination

Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.

Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...

Im Focus: Perovskite edges can be tuned for optoelectronic performance

Layered 2D material improves efficiency for solar cells and LEDs

In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...

Im Focus: Polymer-coated silicon nanosheets as alternative to graphene: A perfect team for nanoelectronics

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.

Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

International Land Use Symposium ILUS 2017: Call for Abstracts and Registration open

20.03.2017 | Event News

CONNECT 2017: International congress on connective tissue

14.03.2017 | Event News

ICTM Conference: Turbine Construction between Big Data and Additive Manufacturing

07.03.2017 | Event News

 
Latest News

NASA laser communications to provide Orion faster connections

30.03.2017 | Physics and Astronomy

Reusable carbon nanotubes could be the water filter of the future, says RIT study

30.03.2017 | Studies and Analyses

Unique genome architectures after fertilisation in single-cell embryos

30.03.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>