[Terrapreta] Durability of charcoal as carbon sink?

[AJH]

On Sat, 2 Jun 2007 11:29:06 -0500, Sean K. Barry wrote:

> As for the resilience or durability of charcoal in soil?  I need to believe that someone can devise an experiment around the hypothesis that it is quite durable.
>
>Here is my attempt at designing such an experiment (any comments are welcome?)

No comment about the experiment but I don't think the results will
affect the practical side much, the simple fact is, using
"agricultural" type devices you have few options. At the extremes you
can make 99% fixed carbon char with ~15% yield or 78% fixed carbon at
45% yield.

As no one seems to disagree that the fixed carbon will be sequestrated
almost permanently and there is only debate about the other carbon
then plainly we get most "agreed" carbon sequestrated by burying the
high volatile char as per unit of dry wood input this sequestrates
235% as much fixed carbon as the higher carbon char.

Two other small points as I have been trying to catch up with your
writings you have pointed out other gases have a CO2 equivalent effect
which is measured as a multiple of the same mass of CO2. You said your
charcoal making method did not flare smokelessly yet we know the
pyrolysis offgas contains a number of greenhouse gases with CO2
equivalents of more than one. So how can one reconcile attempting to
solve one problem by creating another?

Similarly it amuses me how people can be expected to be taken
seriously in their attempts to save the world when they are unwilling
to offer the simple courtesy of conserving bandwidth by removing
irrelevant text.

Andrew Heggie