Do Plants Contribute to Methane Emissions?

[Mk]

http://www.nature.com/nature/journal/v439/n7073/abs/nature04420.html
http://www.nature-science.info/news/07042702.htm[/URL]
[quote]Plants were grown in a facility containing atmospheric carbon dioxide almost exclusively with a heavy form of carbon (13C). This makes the carbon released from the plants relatively easy to detect. Thus, if plants are able to emit methane, it will contain the heavy carbon isotope and can be detected against the background of lighter carbon molecules in the air.

Six plant species were grown in a 13C-carbon dioxide atmosphere, saturating the plants with heavy carbon. 13C-Methane emission was measured under controlled, but natural conditions with a photo-acoustic laser technique. This technique is so sensitive that the scientists are able to measure the carbon dioxide in the breath of small insects like ants. Even with this state-of-the-art technique, the measured emission rates were so close to the detection limit that they did not statistically differ from zero. To our knowledge this is the first independent test which has been published since the controversy last year.

Conscious of the fact that a small amount of plant material might only result in small amounts of methane, the researchers sampled the ‘heavy’ methane in the air in which a large amount of plants were growing. Again, the measured methane emissions were neglible. Thus these plant specialists conclude that there is no reason to reassess the mitigation potential of plants. The researchers stress that questions still remain and that the gap in the global methane budget needs to be properly addressed.[/quote]

 

[Greg Bernhardt]

I would like to address the findings presented in the forum post regarding the potential emission of methane from plants. The study mentioned in the post is a significant contribution to the ongoing discussion on the role of plants in the global methane budget.

The use of a 13C-carbon dioxide atmosphere to saturate the plants and the sensitive photo-acoustic laser technique used to measure methane emissions are both robust methods. The fact that the measured emissions were close to the detection limit and did not statistically differ from zero is a strong indication that plants do not emit significant amounts of methane under controlled, natural conditions.

Furthermore, the researchers also sampled the air in which a large amount of plants were growing and found that the methane emissions were negligible. This provides additional evidence that plants do not contribute significantly to the global methane budget.

However, it is important to note that further research is needed to fully understand the role of plants in the global methane budget. While this study provides valuable insights, it is just one piece of the puzzle and there may be other factors that need to be considered.

In conclusion, based on the findings presented in the forum post, it can be confidently stated that there is no reason to reassess the mitigation potential of plants in regards to methane emissions. This study serves as a reminder that the scientific community must continue to investigate and address gaps in our understanding of the global methane budget in order to effectively mitigate its impact on our environment.