Bamboo "hailed as the 21st century timber" - they must be joking

tarafından: Rupert Oliver in Environment

According to the April issue of the BBC magazine bamboo is being "hailed as the 21st century timber" (http://www.bbc.co.uk/news/magazine-17568088) Bamboo may be a relatively benign product environmentally, but wood’s environmental profile will often be better.

It should be said that the BBC's tag line is a bit misleading - the article's author - the BBC's World Affairs Correspondent Mike Wooldridge - is mainly concerned about a project in Nicaragua and appears sceptical of the more far-reaching claims of the bamboo industry. There is, for example, mention of the potential downside of encouraging use of products from intensive monocultures and lack of any international standards for sustainable production of bamboo.

But the article seriously short-changes the wood sector. The report acknowledges that bamboo in Nicaragua is grown on land previously under tropical forest, but it doesn't then raise the obvious question of whether rising demand for bamboo might threaten the remaining remnants of forest. A simplistic single issue comparison is made between timber production ("trees require a long time to grow") and bamboo (which has the single merit of being quick to grow) without any attempt to put this into the wider environmental context. So no mention is made of the fact that sustainable selection harvesting of semi-natural forest (typical in the hardwood industry) allows income generation while also maintaining biodiversity. Nor of the fact that such forest management requires relatively little energy (no fertiliser, replanting or weeding required) and also helps protect watersheds. Contrast this with bamboo plantations which require regular and intensive management, must be given ample water, actively protected from competitive weeds and, in many areas, require application of fertiliser.

The article's introduction suggests that bamboo has potential to "absorb large amounts of carbon dioxide", but doesn't then elaborate on this. While growing bamboo (like wood) certainly sequesters CO2, there's no guarantee that the overall carbon footprint will be negative (i.e. more carbon ends up in stored in the finished product than is emitted in getting that product to market). Not only does bamboo require a relatively large amount of energy to grow, but also to process. To produce bamboo flooring, for example, the outer skin of the bamboo stem must be removed, and then the stem is cut into strips which are treated against mould and insects. The strips may then be boiled (steamed) to turn the material a caramel brown colour. The strips are then kiln dried, pressed and glued together under high pressure. All of this requires energy and leads to carbon emissions.

That's not to say that bamboo is necessarily better or worse for the environment than hardwood or any other material. Some bamboo products may well contribute to carbon sequestration and in some circumstances - such as those in Nicaragua described in the BBC article - bamboo production might be a sound environmental and social option. Elsewhere, sustainable management of forests for hardwoods will be the better option. The only way to make valid judgements of environmental impact is by comparing each product on a full cradle to grave basis.