Bill, Indeed. I should also point out that logging increases C respiration from decay woody debris and increased sol temperature...
IMHO: he only form of biofuel production that is sustainable, and C neutral, is waste conversion. I.e biodiesel from waste oil, ethanol from waste cellulose and methane from manure. While all do include some energy inputs, so does waste disposal and it does not provide any energy benefits. I doubt however if a corporate infrastructure of biofuel production can avoid being seduced by the lure of sustainable profits from unsustainable biomass to energy from primary agricultural sources . David On Jan 15, 2008, at 5:38 AM, William Silvert wrote: > Although David is correct about long-term carbon budgets, this too > is an > oversimplification. Biomass is a form of carbon sequestration, and > when > forests are cut down to develop biofuel plantations, as is > happening in > Indonesia and elsewhere, a lot of carbon is removed and ultimately > gets into > atmospheric CO2. Furthermore much biofuel production is energy- > intensive, > perhaps the worst example being the growth of corn in the US where > much > energy goes into the production of fertilizers and pesticides, as > well as > irrigation. And of course there are other environmental costs in > addition to > energy. > > So far as I am aware, the only significant forms of carbon > sequestration are > biomass and carbonates -- am I wrong about this? Maintenance of > high forest > biomass can help, and as for carbonates, I think the main mechanism is > through creation of calcium carbonate by marine organisms, which we > can't do > much about. Perhaps someone has better information, but it seems to > me that > it is highly desirable both to reduce the consumption of fossil > fuels and to > promote conservation of high plant biomass. > > Bill Silvert > > > ----- Original Message ----- > From: "David Bryant" <[EMAIL PROTECTED]> > To: <[email protected]> > Sent: Monday, January 14, 2008 10:24 PM > Subject: Re: ESA Press Release: Nation's Ecological Scientists > weigh in on > biofuels > > >> This statement that biofuels are combustables, and therefore give off >> CO2, is a commonly promoted oversimplification, oft stated by less- >> than-knowledgeable reporters. The carbon in biofuels WAS in the >> atmosphere last winter/growing season (depending on your latitude) >> and therefore biofuels are technically C neutral from the perspective >> of the C Cycle. Just like the rain/snow that falls on us today was >> in the ocean days/weeks before and does not contribute to the sea >> surface level rise.
