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

Perhaps there was a thread was about Terre Pieta, but my specific comment was about charcoal.  I believe I clearly indicated my response as being about charcoal. 
Charcoal by definition is wood held at high temperature (175 to 180 C) with low oxygen (doesn't burn but essentially crystallizes).  This can be done mechanically, or can be done by biology. 
If someone wants to develop a new term, for example "char", then a clear definition is required.  Conditions for production of that material need to be defined.  
When people compost using woody materials, such as oak, pine, cedar, eucalyptus, or other wide C:N bark, heartwood or sapwood, with other materials (green plant material and high N containing material) on which the bacteria and fungi grow rapidly, use up oxygen, and generate high heat (above 170 C), then conditions are correct to produce charcoal. 
Compost is NOT sterile at 175 C.  Just because none of the organisms growing at those temperatures will grow on any lab culture plate, does not mean those organisms do not exist. 
But many conventional microbiology-based people make that mistake.  There are a huge number of species and high numbers of individuals at high temperatures.  Take a look at deep sea vents.  Check out the number of species in a ml of seawater, regardless of whether that water is from deep ocean vents or from near-shore, or mid-depth. 
The reason that compost piles heat is through the heat released at the organisms grow.  No organisms, no heat in a compost pile.  If you have heat, you have growing organisms. 
In Terre Pieta, there are a huge number of organisms.  Which is more likely to be more important to the production of the fertility of this soil?  Charcoal, the charred organic matter, or the organisms?
If you have a material that is compacted, it often lacks oxygen.  Mycorrhizal fungi are strict aerobes, and cannot grow when oxygen is lacking.  If material that structurally helps oxygen move more easily into the material is added, the mycorrhizal fungi will be seen to grow more readily as the conditions restricting their growth are alleviated. 
Did the structural material supply carbon?  mineral nutrients?  or allow oxygen to move into the material? 
What is the real explanation for the benefit of charcoal for mycorrhizal growth?
Elaine Ingham
In a message dated 9/13/2006 3:59:48 P.M. Pacific Daylight Time, nosliwelad@YAHOO.COM writes:

> 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.

Elaine R. Ingham
Soil Foodweb Inc., Corvallis, Oregon
Soil Foodweb Inc., Port Jefferson, New York
Soil Foodweb Institute, Lismore Australia
Soil Foodweb Institute Cambridge, New Zealand
Laboratorios de Soil Foodweb, Culiacan, Mexico
Soil Foodweb South Africa, Polokwane, SA
Soil Foodweb Canada, Vulcan, Alberta, Canada
Soil Foodweb United Kingdom, Laverstoke Park, UK
Coming soon -a second lab in Canada, one in Kenya, and in Japan!



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