Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

USDA Scientists Study Effects of Rising Carbon Dioxide on Rangelands

04.08.2011
Rising carbon dioxide (CO2) levels can reverse the drying effects of predicted higher temperatures on semi-arid rangelands, according to a study published today in the scientific journal Nature by a team of U.S. Department of Agriculture (USDA) and university scientists.

Warmer temperatures increase water loss to the atmosphere, leading to drier soils. In contrast, higher CO2 levels cause leaf stomatal pores to partly close, lessening the amount of water vapor that escapes and the amount of water plants draw from soil.

This new study finds that CO2 does more to counterbalance warming-induced water loss than previously expected. In fact, simulations of levels of warming and CO2 predicted for later this century demonstrated no net change in soil water, and actually increased levels of plant growth for warm-season grasses.

"By combining higher temperatures with elevated CO2 levels in an experiment on actual rangeland, these researchers are developing the scientific knowledge base to help prepare managers of the world's rangelands for what is likely to happen as climate changes in the future," said Edward B. Knipling, administrator of the Agricultural Research Service (ARS), USDA's principal intramural scientific research agency.

The results cover the first four years of the eight-year Prairie Heating and CO2 Enrichment (PHACE) experiment on native northern mixed grass rangeland. The study is being conducted by the ARS Rangeland Resources Research Unit (RRRU) at the High Plains Grasslands Research Station near Cheyenne, Wyo.

ARS plant physiologist Jack Morgan leads the study, which uses both CO2 pipelines and thermal infrared heaters to simulate global warming conditions predicted for the end of the century: 600 parts per million (ppm) of CO2—compared to today's average 390 ppm—and day/night temperatures raised by 3 and 5 degrees Fahrenheit, respectively.

Based on these findings, warmer temperatures would likely play a role in changing the relative success of various grass types. "Only the warm-season grasses had their growth boosted higher by CO2 and warmer temperatures," Morgan said. "If this leads to a competitive advantage for warm-season grasses, it may increase the challenges faced by ranchers who desire cool-season grasses for early-season forage."

Elise Pendall and David Williams at the University of Wyoming at Laramie and Matthew Wallenstein at Colorado State University at Fort Collins also are participating in the study, which will be completed in 2013. Retired ARS soil scientist Bruce Kimball, designer of the infrared heater system, is helping conduct the study. Kimball serves as a research collaborator at the ARS U.S. Arid-Land Agricultural Research Center in Maricopa, Ariz.

Grass-dominated, dry rangelands account for approximately a third of the Earth's land surface, providing most of the forage eaten by livestock. This research, the first of its kind on this scale for rangelands, supports the USDA priority of helping farmers and ranchers throughout the United States and the rest of the world best adapt production practices to variable climate patterns.

Morgan said more research is needed to determine how the water-savings effect applies over the long run and in other types of semi-arid rangelands as well as to croplands in semi-arid areas. "It is important to understand that CO2 only offset the direct effects of warming on soil water in this experiment, and that it is unlikely to offset more severe drought due to combined warming and reduced precipitation projected for many regions of the world," he said.

In addition to ARS funding, the research is supported by grants from the National Science Foundation, the U.S. Department of Energy, and USDA's National Institute of Food and Agriculture.

Don Comis | EurekAlert!
Further information:
http://www.ars.usda.gov

Further reports about: ARS Agricultural Research CO2 CO2 levels Carbon agriculture dioxide warmer temperatures

More articles from Agricultural and Forestry Science:

nachricht Energy crop production on conservation lands may not boost greenhouse gases
13.03.2017 | Penn State

nachricht How nature creates forest diversity
07.03.2017 | International Institute for Applied Systems Analysis (IIASA)

All articles from Agricultural and Forestry Science >>>

The most recent press releases about innovation >>>

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

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...

Im Focus: Researchers Imitate Molecular Crowding in Cells

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.

Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...

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

Argon is not the 'dope' for metallic hydrogen

24.03.2017 | Materials Sciences

Astronomers find unexpected, dust-obscured star formation in distant galaxy

24.03.2017 | Physics and Astronomy

Gravitational wave kicks monster black hole out of galactic core

24.03.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>