BLOG PAGES

Sep 26, 2010

Biochar: is it any good?

Last March, George Monbiot has an attack on biochar. It has just been circulated to me by email to an influential list. George Monbiot is using the old journalistic trick of totalising the discussion, setting up an Aunt Sally. He says it has been advanced as a "Miracle" and the "universal answer to our climate and energy problems". Biochar is not a miracle, it is an interesting agricultural technique with carbon-storage spinoffs. Biochar is not, suddenly or otherwise, the "universal answer to our climate and energy problems" - it is an interesting pathway of remediation that should be investigated and evaluated by gardeners and agriculturalists, alongside other changes in the way we do things. The fact is that every day, solar energy acting on chlorophyll causes carbon dioxide and water to form sugars in leaves, some of which turn into xylem, are a store of energy and carbon. Left to itself, this store falls and rots, creating methane, thirty times more effective as a greenhouse gas than CO2. If we can pollibly divert some of this process into a long-term carbon store, while at the same time increasing food production, then it is entirely reasonable to experiment to see how this can be done in a way that helps biodiversity, helps local economies and local communities, and makes a contribution to stabilising our environment and society, alongside the radical decarbonisation of our energy Sure, there may be un-green industrial scale plans for biochar that are ill-thought through, have adverse consequences, and should be opposed. This does not mean that I as a gardener should not experiment with adding charcoal to my soil. To be fair, George does admit of this possibility, so our disagreement is one of emphasis and approach, rather than of total difference. We must always remember that even if it were possible by magic to stop all CO2 emissions tomorrow, we would still need to find a way to draw sequester the excess CO2 that we have already put in the atmosphere. There is no merit in the argument "We must not try to sequester CO2 before we have fully decarbonised the economy". We should also remember that it is possible to walk and chew gum at one and the same time.

No comments:

Post a Comment