Plants do not emit methane

Scientists disprove a recent study that suggests plants emit the potent greenhouse gas methane

A recent study in Nature¹ suggested that terrestrial plants may be a global source of the potent greenhouse gas methane, making plants substantial contributors to the annual global methane budget. This controversial finding and the resulting commotion triggered a consortium² of Dutch scientists to re-examine this in an independent study. Reporting in New Phytologist, Tom Dueck and colleagues present their results and conclude that methane emissions from plants are negligible and do not contribute to global climate change.

The consortium brings together a unique combination of expertise and facilities enabling the design and execution of a novel experiment. 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.