RxPG News XML Feed for RxPG News   Add RxPG News Headlines to My Yahoo!  

Medical Research Health Special Topics World
 
  Home
 
 Careers 
 Dental
 Medical
 Nursing
 
 Latest Research 
 Aging
 Anaethesia
 Biochemistry
 Biotechnology
 Cancer
 Cardiology
 Clinical Trials
 Cytology
 Dental
 Dermatology
 Embryology
 Endocrinology
 ENT
 Environment
 Gastroenterology
 Genetics
 Gynaecology
 Haematology
 Immunology
 Infectious Diseases
 Metabolism
 Microbiology
 Musculoskeletal
 Nephrology
 Neurosciences
 Obstetrics
 Ophthalmology
 Orthopedics
 Paediatrics
 Pathology
 Pharmacology
 Physiology
 Psychiatry
 Public Health
 Radiology
 Rheumatology
 Surgery
 Urology
 Alternative Medicine
 Medicine
 Epidemiology
 Sports Medicine
 Toxicology
 
 Medical News 
 Awards & Prizes
 Epidemics
 Health
 Healthcare
 Launch
 Opinion
 Professionals
 
 Special Topics 
 Ethics
 Euthanasia
 Evolution
 Feature
 Odd Medical News
 Climate
 
 DocIndia 
 Reservation Issue
 Overseas Indian Doctor

Last Updated: May 20, 2007 - 10:48:48 AM
News Report
Europe Channel

subscribe to Europe newsletter
Europe

   EMAIL   |   PRINT
Scientist says trees worsen greenhouse effect, stirs debate
May 15, 2007 - 8:00:48 AM
But Keppler rejects this, saying that this sort of methane desorption could only be partially responsible for the amounts of gas he found.

Article options
 Email to a Friend
 Printer friendly version
 Europe channel RSS
 More Europe news
[RxPG] Hamburg, May 15 - A leading expert in Germany has spawned a major scientific debate by claiming that trees put millions of tonnes of methane into the atmosphere every year exacerbating the greenhouse effect.

Amid controversy, Frank Keppler of the Max Planck Institute for Chemistry has reaffirmed findings by his team in Mainz, Germany, in January 2006 that they had detected methane exhaled from living plants.

'I am 100 percent confident that plants emit methane,' he told Chemistry World magazine, insisting that as yet unpublished research would confirm his findings once and for all.

Keppler's unexpected discovery has caused heated debate among biologists and atmospheric chemists. Though bacteria in soil or decaying matter produce methane in anaerobic conditions, there seems to be no reason or mechanism for living plants to emit the gas in an oxygen-rich environment.

The implications of the findings are worrying: on a global scale, Keppler estimated, methane emissions from plants and trees could amount to hundreds of millions of tonnes a year, throwing scientists' understanding of the greenhouse gas's sources and sinks way off kilter.

But many researchers have queried the global impact, suggesting that Keppler's scale-up calculations, based on methane emission per unit of metabolically active mass of plant, were a gross overestimate.

Yet until recently, no published research has questioned Keppler's central discovery that plants can emit methane in the first place.

Recently, however, rival researchers reported that plants emit virtually no methane whatsoever.

Tom Dueck, of Wageningen University in the Netherlands, says his team's independent investigations are the first published results to show that plants' methane emissions are negligible or zero. That means their contribution to the global methane budget, and potentially to climate change, simply isn't worth worrying about.

The Dutch group did not repeat Keppler's experiment exactly, Dueck said, 'because it was not methodologically sound.' Instead, his team boosted the sensitivity of their methane measurements by growing plants in an atmosphere saturated with a heavy carbon isotope, 13C.

If the plants subsequently emitted methane -, it would be easy to spot above the background of light - methane in the air. Photo-acoustic spectroscopy - was used to detect the gas.

Dueck said it showed that even a large mass of plants produced negligible methane emissions - at most 0.3 percent of Keppler's values.

So if Dueck's team is correct, where did Keppler go wrong? Dueck suggests that Keppler's team might have forgotten that gas trapped in plants' intercellular spaces, and in air pockets in the soil, could diffuse out and be counted as 'emitted' by the plant in their experiment.

But Keppler rejects this, saying that this sort of methane desorption could only be partially responsible for the amounts of gas he found.

Indeed, he suggests that Dueck's use of heavy isotopes may have actually changed the plants' metabolic preferences, killing off their methane emissions. Dueck counters that no literature reports suggest this might be a problem.





Related Europe News
Moore returns to Cannes with scathing look at healthcare
India section kicks off at Cannes
Nesta extends contract with AC Milan until 2011
Federer, Nadal roll on into Hamburg semis
Fingerprint could identify smoker, drinker
Devil or wily lawyer - Cannes film looks at Jacques Verges
French president unveils new cabinet
'Blair could be in run for World Bank top job'
India's growing economic clout high on Brown's agenda
Roma snatch Italian Cup from Inter

Subscribe to Europe Newsletter
E-mail Address:

 Feedback
For any corrections of factual information, to contact the editors or to send any medical news or health news press releases, use feedback form

Top of Page

 
© All rights reserved 2004 onwards by RxPG Medical Solutions Private Limited
Contact Us