Featured Research

from universities, journals, and other organizations

Rising carbon dioxide could reverse drying effects of higher temperatures on rangelands

Date:
August 4, 2011
Source:
USDA/Agricultural Research Service
Summary:
Rising carbon dioxide levels can reverse the drying effects of predicted higher temperatures on semi-arid rangelands, according to a new study by a team of US Department of Agriculture and university scientists.

ARS plant physiologist Jack Morgan is leader of a group replicating anticipated higher carbon dioxide and temperature levels to study their impact on semi-arid rangeland grasses.
Credit: Image courtesy of USDA/Agricultural Research Service

Rising carbon dioxide (CO2) levels can reverse the drying effects of predicted higher temperatures on semi-arid rangelands, according to a study published in the 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 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.


Story Source:

The above story is based on materials provided by USDA/Agricultural Research Service. The original article was written by Don Comis. Note: Materials may be edited for content and length.


Journal Reference:

  1. Jack A. Morgan, Daniel R. LeCain, Elise Pendall, Dana M. Blumenthal, Bruce A. Kimball, Yolima Carrillo, David G. Williams, Jana Heisler-White, Feike A. Dijkstra, Mark West. C4 grasses prosper as carbon dioxide eliminates desiccation in warmed semi-arid grassland. Nature, 2011; DOI: 10.1038/nature10274

Cite This Page:

USDA/Agricultural Research Service. "Rising carbon dioxide could reverse drying effects of higher temperatures on rangelands." ScienceDaily. ScienceDaily, 4 August 2011. <www.sciencedaily.com/releases/2011/08/110803143140.htm>.
USDA/Agricultural Research Service. (2011, August 4). Rising carbon dioxide could reverse drying effects of higher temperatures on rangelands. ScienceDaily. Retrieved July 25, 2014 from www.sciencedaily.com/releases/2011/08/110803143140.htm
USDA/Agricultural Research Service. "Rising carbon dioxide could reverse drying effects of higher temperatures on rangelands." ScienceDaily. www.sciencedaily.com/releases/2011/08/110803143140.htm (accessed July 25, 2014).

Share This




More Earth & Climate News

Friday, July 25, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Goma Cheese Brings Whiff of New Hope to DRC

Goma Cheese Brings Whiff of New Hope to DRC

Reuters - Business Video Online (July 24, 2014) The eastern region of the Democratic Republic of Congo, mainly known for conflict and instability, is an unlikely place for the production of fine cheese. But a farm in the village of Masisi, in North Kivu is slowly transforming perceptions of the area. Known simply as Goma cheese, the Congolese version of Dutch gouda has gained popularity through out the region. Ciara Sutton reports. Video provided by Reuters
Powered by NewsLook.com
Bill Gates: Health, Agriculture Key to Africa's Development

Bill Gates: Health, Agriculture Key to Africa's Development

AFP (July 24, 2014) Health and agriculture development are key if African countries are to overcome poverty and grow, US software billionaire Bill Gates said Thursday, as he received an honourary degree in Ethiopia. Duration: 00:36 Video provided by AFP
Powered by NewsLook.com
Higgins Breaks Record at Mt. Washington

Higgins Breaks Record at Mt. Washington

Driving Sports (July 24, 2014) Subaru Rally Team USA drivers David Higgins and Travis Pastrana face off against a global contingent of racers at the annual Mt. Washington Hillclimb in New Hampshire. Includes exclusive in-car footage from Higgins' record attempt. Video provided by Driving Sports
Powered by NewsLook.com
Storm Kills Three, Injures 20 at Virginia Campground

Storm Kills Three, Injures 20 at Virginia Campground

Reuters - US Online Video (July 24, 2014) A likely tornado tears through an eastern Virginia campground, killing three and injuring at least 20. Linda So reports. Video provided by Reuters
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

    Health News

      Environment News

        Technology News



          Save/Print:
          Share:

          Free Subscriptions


          Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

          Get Social & Mobile


          Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

          Have Feedback?


          Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
          Mobile: iPhone Android Web
          Follow: Facebook Twitter Google+
          Subscribe: RSS Feeds Email Newsletters
          Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins