Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Urban 'green' spaces may contribute to global warming

19.02.2010
This press release has been updated to reflect the correction of a spreadsheet error in the scientific paper regarding carbon dioxide emissions during lawn maintenance. The correction, published 27 March, is available as stated in "Notes for Journalists" at the end of this release.

Challenging the notion that urban “green” spaces help counteract greenhouse gas emissions, new research has found — in Southern California at least — that mowing and other lawn maintenance emit almost as much or more greenhouse gases than the well-tended grass extracts from the air.

Turfgrass lawns remove carbon dioxide from the atmosphere through photosynthesis and store it as organic carbon in soil, making them important “carbon sinks.” However, greenhouse gas emissions from fertilizer production, mowing, leaf blowing and other lawn management practices are similar to or greater than the amount of carbon stored by ornamental grass in parks, a new study shows. These emissions include nitrous oxide released from soil after fertilization. Nitrous oxide is a greenhouse gas that's 300 times more powerful than carbon dioxide, the Earth’s most problematic climate warmer.

Previous studies have documented lawns storing carbon, but this research was the first to compare carbon sequestration to nitrous oxide and carbon dioxide emissions from lawn grooming practices.

“Lawns look great — they're nice and green and healthy, and they're photosynthesizing a lot of organic carbon. But the carbon-storing benefits of lawns can be counteracted by greenhouse gas emissions,” says Amy Townsend-Small, Earth system science postdoctoral researcher at University of California, Irvine. Townsend-Small is the lead author of the study, which has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union (AGU).

The research results are important to greenhouse gas legislation being negotiated, Townsend-Small says. “We need this kind of carbon accounting to help reduce global warming,” the lead author says. “The current trend is to count the carbon sinks and forget about the greenhouse gas emissions, but it clearly isn't enough.”

Turfgrass is increasingly widespread in urban areas and covers 1.9 percent of land in the continental U.S., making it the most common irrigated crop.

In the study, Townsend-Small and colleague Claudia Czimczik analyze grass in four parks near Irvine, Calif. Each park contains two types of turf: ornamental lawns (picnic areas) that are largely undisturbed, and athletic fields (soccer and baseball) that are trampled a lot and replanted and aerated frequently.

The researchers took and evaluated soil samples over time to ascertain carbon storage, or sequestration, and they determined nitrous oxide emissions by sampling air above the turf. Then they calculated carbon dioxide emissions resulting from fuel consumption, irrigation and fertilizer production using information about lawn upkeep from park officials and contractors.

The study shows that nitrous oxide emissions from lawns are comparable to those found in agricultural farms, which are among the largest emitters of nitrous oxide globally.

In ornamental lawns, nitrous oxide emissions from fertilization offset just 10 percent to 30 percent of carbon sequestration. But fossil fuel consumption for management, the researchers calculate, releases about almost as much or more carbon dioxide than the plots can take up, depending on management intensity. Athletic fields fare even worse, because — due to soil disruption by tilling and resodding — they don't trap nearly as much carbon as ornamental grass but require the same emissions-producing care.

“It's unlikely for these lawns to act as net greenhouse gas sinks because too much energy is used to maintain them,” Townsend-Small concludes.

The UCI study was supported by the Kearney Foundation of Soil Science and the U.S. Department of Agriculture.

Notes for Journalists
Journalists and public information officers (PIOs) of educational and scientific institutions who have registered with AGU can download a PDF copy of this correction.

The 22 January paper altered by the Correction can be downloaded.

Or, you may order copies of the Correction and/or the original paper by emailing your request to Peter Weiss at pweiss@agu.org, or Cathy Lawhon at clawhon@uci.edu. Please provide your name, the name of your publication, and your phone number.

Neither the Correction nor the original paper are under embargo.

News radio
UCI maintains on campus an ISDN line for conducting interviews with its faculty and experts. Use of this line is available for a fee to radio news programs/stations that wish to interview UCI faculty and experts. Use of the ISDN line is subject to availability and approval by the university.
Title
“Carbon sequestration and greenhouse gas emissions in urban turf”
Authors
Amy Townsend-Small and Claudia I. Czimczik: Department of Earth System Science, University of California, Irvine, Calif., USA.
Contact information for the author
Amy Townsend-Small, UC Irvine scientist. Tel: +1 (949) 824-2935, email: atownsen@uci.edu

Jennifer Fitzenberger | EurekAlert!
Further information:
http://www.uci.edu
http://www.today.uci.edu

More articles from Earth Sciences:

nachricht Six-decade-old space mystery solved with shoebox-sized satellite called a CubeSat
15.12.2017 | National Science Foundation

nachricht NSF-funded researchers find that ice sheet is dynamic and has repeatedly grown and shrunk
15.12.2017 | National Science Foundation

All articles from Earth Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: First-of-its-kind chemical oscillator offers new level of molecular control

DNA molecules that follow specific instructions could offer more precise molecular control of synthetic chemical systems, a discovery that opens the door for engineers to create molecular machines with new and complex behaviors.

Researchers have created chemical amplifiers and a chemical oscillator using a systematic method that has the potential to embed sophisticated circuit...

Im Focus: Long-lived storage of a photonic qubit for worldwide teleportation

MPQ scientists achieve long storage times for photonic quantum bits which break the lower bound for direct teleportation in a global quantum network.

Concerning the development of quantum memories for the realization of global quantum networks, scientists of the Quantum Dynamics Division led by Professor...

Im Focus: Electromagnetic water cloak eliminates drag and wake

Detailed calculations show water cloaks are feasible with today's technology

Researchers have developed a water cloaking concept based on electromagnetic forces that could eliminate an object's wake, greatly reducing its drag while...

Im Focus: Scientists channel graphene to understand filtration and ion transport into cells

Tiny pores at a cell's entryway act as miniature bouncers, letting in some electrically charged atoms--ions--but blocking others. Operating as exquisitely sensitive filters, these "ion channels" play a critical role in biological functions such as muscle contraction and the firing of brain cells.

To rapidly transport the right ions through the cell membrane, the tiny channels rely on a complex interplay between the ions and surrounding molecules,...

Im Focus: Towards data storage at the single molecule level

The miniaturization of the current technology of storage media is hindered by fundamental limits of quantum mechanics. A new approach consists in using so-called spin-crossover molecules as the smallest possible storage unit. Similar to normal hard drives, these special molecules can save information via their magnetic state. A research team from Kiel University has now managed to successfully place a new class of spin-crossover molecules onto a surface and to improve the molecule’s storage capacity. The storage density of conventional hard drives could therefore theoretically be increased by more than one hundred fold. The study has been published in the scientific journal Nano Letters.

Over the past few years, the building blocks of storage media have gotten ever smaller. But further miniaturization of the current technology is hindered by...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

See, understand and experience the work of the future

11.12.2017 | Event News

Innovative strategies to tackle parasitic worms

08.12.2017 | Event News

AKL’18: The opportunities and challenges of digitalization in the laser industry

07.12.2017 | Event News

 
Latest News

Engineers program tiny robots to move, think like insects

15.12.2017 | Power and Electrical Engineering

One in 5 materials chemistry papers may be wrong, study suggests

15.12.2017 | Materials Sciences

New antbird species discovered in Peru by LSU ornithologists

15.12.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>