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Re: [SANET-MG] Putting the carbon back: Black is the new green


> Charcoal addition, WITHOUT ANY organisms, nutrient, or water
> addition with it, was what was being discussed.  If you wish to
> add in other factors, along with the charcoal,  then the 
> discussion will be very different.

Part of the discussion is the indeterminacy of the term "charcoal." 
This subject is already "very different" because things other than pure
thermogenic carbon are present in "char."

> If you want to add all the other things besides charcoal that
> are in Terra Preta, i.e., if you want to add bacteria, fungi,
> protozoa, nematodes, microarthropods, humus, fulvics, proteins,
> sugars. etc then we aren't talking  about just charcoal anymore.

That is part of the point of this discussion.  The "char" being
discussed is a complex material.
> How long has it been since "black earth" was anaerobic?  It
> does not has a sickening, stinky smell to it as it has been
> described to me.  It is not low in oxygen.  It is not hot.
> Terra Preta is not charcoal.

"Because of their elevated charcoal content, it is now widely accepted
that these soils are a product of indigenous soil management involving
a labor intensive technique termed slash-and-char. The technique is
differentiated from slash and burn by a lower temperature burn and in
being a tool for soil improvement. Amending soil with low temperature
charcoal produced from a mix of wood and leafy biomass (termed
bio-char) has been observed to increase the activity of arbuscular
mycorrhizal fungi."

> Recalcitrance of any organic matter is relative, and I'll agree
> with Lutzow et all absolutely on that statement.  If you have no
> fungi in the "mix", the wider C:N materials are going to have a
> hard time breaking down.  If the fungi that can use that wide
> C:N material are present, those "recalcitrant" materials can
> disappear pretty quickly.

The other part of this discussion, is the possibility that by thermally
processing organic matter in the right way, it might be possible to
very greatly increase the recalcitrance of the organic matter, while
retaining soil-building value (beyond the value of ordinary charcoal). 
This seems to be what happened to these Terra Preta soils.  Thermal
processing might be a valuable way to make microbiologically stable OM
> If organic matter has been sterilized, or does not contain the
> organisms capable of breaking down the bonds in the material,
> then that material will appear "recalcitrant".

We are not talking about sterile systems.  Sure, the biomass being
thermally processed would be rendered sterile, but after you put it in
the soil it will be colonized by the native flora and fauna.
> Restrict the information being considered to just what I was
> talking about, and do NOT add in all sorts of other things.
> Please don't muddy the conversation that was being held.

Elaine, it it too late!  This was a murky, confusing, impure thread
from it's inception.  I would urge you to keep an open mind.  I don't
think this is mainly about "charcoal" in the usual sense of the word.


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