19 January 2006
Researchers Slam Media Over Wrong-Headed Plant-Methane Hype
by Kate Melville
The researchers who found that plants emit significant quantities of the greenhouse gas methane have come out swinging at what they believe is widespread "misinterpretation of the findings" by worldwide media.
The original study in Nature, conducted by scientists from the Max Planck Institute for Nuclear Physics and the Department of Agriculture and Rural Development for Northern Ireland, revealed that plants produce the greenhouse gas methane.
The scientists say that while there has been extended media coverage of this work, in many instances, it is based on a misinterpretation of the findings. They are concerned that that this misinterpretation may undermine reforestation programs in the framework of the Kyoto protocol and have issued a clarification explaining the findings in detail.
According to the researchers, the most frequent misinterpretation was that the emission of methane from plants was responsible for global warming. They explain that these emissions have existed since long before man arrived on the scene and that plant emissions are part of what they call "the natural greenhouse effect." These emissions should not be confused with the anthropogenic (man-made) emissions which are responsible for the well-documented increasing atmospheric concentrations of methane since pre-industrial times. The researchers added that even if land use practices have altered plant methane emissions (which the study did not examine), this would also be regarded as an anthropogenic source.
The original study also fueled intense speculation that methane emissions by plants could diminish, or even outweigh, the carbon storage effect of reforestation programs, with important implications for the Kyoto protocol, where such programs are to be used in carbon dioxide reduction strategies.
The researchers say that while these estimates show that methane emissions by plants may slightly diminish the effect of reforestation programs, the climatic benefits gained through carbon sequestration by reforestation far exceed the relatively small negative effect, which may reduce the beneficial carbon uptake effect by around 4 percent. They add that, "the potential for reduction of global warming by planting trees is most definitely positive. The fundamental problem still remaining is the global large-scale anthropogenic burning of fossil fuels."
Source: Max Planck Institute