Bad news for Bush over his 'plans' to buy off CO2 emissions with tree planting (never mind existing forests). Apparently, apart perhaps from the first 2-3 years of growth, trees and forests aren't such good carbon sinks as some assume... nor is the soil:
Researchers in the US are shedding doubt on how effective trees are in absorbing carbon dioxide (CO2) and then releasing oxygen back into the atmosphere. And they say they have identified factors that limit the ability of these natural "sinks" to soak up CO2.
...
The total amount of litter did increase in a carbon-enriched atmosphere, but the rate at which it broke down also increased. And the carbon then went back into the atmosphere rather than into the soil.
They say: "We report a significant accumulation of carbon in the litter layer of experimental forest plots after three years of growth at increased CO2 concentrations. But fast turnover times of organic carbon in the litter layer (of about three years) appear to constrain the potential size of this carbon sink.
"Given the observation that carbon accumulation in the deeper mineral soil layers was absent, we suggest that significant, long-term net carbon sequestration in forest soils is unlikely."
news.bbc.co.uk
Oh, and 17 National Academies of Science have endorsed the Kyoto aims; the US is only missing because Bush required his own review from them, which should be released in June.
Sir Robert May is president of the UK's Royal Society, one of the academies to sign the statement.
He said: "Some people have unjustifiably sought to undermine the work of the IPCC, but governments should be left in no doubt that it offers the best source of expertise in climate change.
"The developed countries have been responsible for more than two-thirds of emissions over the last 200 years, and it is morally right that they should lead the way."
The statement in Science has been signed by the academies of Australia, Belgium, Brazil, Canada, the Caribbean, China, France, Germany, India, Indonesia, Ireland, Italy, Malaysia, New Zealand, Sweden, Turkey and the UK.
news.bbc.co.uk
Not that I expect this to convince anyone now, but one day... |
