Wednesday, February 14, 2007

Global warming: plants are not to blame - SciDev.Net

Global warming: plants are not to blame - SciDev.Net: "

Plants are not to blame for climate change, according to a statement issued this week (18 January) by the researchers who reported eight days ago that plants emit up to a third of the methane — a potent greenhouse gas — in the atmosphere.

Speaking to SciDev.Net, Keppler said he wanted to make three points clear to the public.

First, their findings do not mean that reforestation programmes should be condemned. Trees absorb carbon dioxide, the most important greenhouse gas, so planting them is still beneficial.

When the methane emitted by trees is taken into account, says Keppler, the benefits of planting trees to absorb atmospheric carbon dioxide diminish by just one to four per cent — a negligible effect.

Secondly, changes in the overall amount of methane emitted by plants — including changes that could worsen global warming — are likely to be caused by human activities such as deforestation.

Finally, they say that much more research is needed to discover how methane emissions from plants vary according to species, temperature, humidity, sunlight and other factors, as well as how these emissions might change as the environment does.