[Terrapreta] some thoughts about Terra Preta

[Christoph Steiner]

I am not convinced if not everything was burned. I frequently had barbecue
with friends when I was living in Manaus and I burned all residues. My
compost was only for plant material with low protein, fat or sugar
content. These materials attract all kind of animals in the tropics. The
animals can be harmful to your crops or to your health. I assume this was
the same for the creators of Terra Preta. After a burn bones easily break
into powder (ash) and pieces. Together with the compost I applied this Ca
and P rich ash together with charcoal in my garden. I assume that this was
creating Terra Preta.
It is right that wood charcoal contains only little amounts of nutrients
(maybe some potassium). But not every charcoal is the same. Peanut husk or
rice husk charcoal is rich in nutrients. The charcoal produced in Japan
from urban wastes is rich in nutrients. This type of charcoal is a real
fertilizer, whereas wood charcoal can be considered rather as soil
conditioner and extra nutrients need to be added.

Best,
Christoph




> Hi Randy,
>
>
> I do not think the carbon in charcoal that is put into soil provides any
> kind of nutrient for plants above the ground or soil microorganisms.
> Charcoal is a lattice for soil microorganisms.  There may be some
> decomposable hydrocarbon strings (volatile matter) left in fresh charcoal
> which microbes can get energy from by decomposing (into CO2 and H2O), but
> char is not a nutrient to plants.  Plants get the carbon they use,
> strictly from the inspiration of CO2 from the atmosphere.  Carbon does not
> form soluble ions in water.  Plants cannot take carbon in through their
> roots.
>
> Also, Terra Preta soils do contain other organic nutrient bearing stuff,
> like fish bones (which contain phosphorus and calcium) and plant wastes
> (the inedible parts of food crops), but it was not charred (not burned
> either).  It was just added into the soil along with charcoal.  Cation
> Exchange Capacity is enhanced in Terra Preta soils.  Some think it has
> more to do with more neutral soil pH and pH buffer capability in TP soils.
> I don't know enough to say why or how it is increased.  Maybe
> Christoph Steiner, Johannes Lehman, or Janice Thies (<- soil scientists)
> could shed more light on that issue.
>
> SKB
> ----- Original Message -----
> From: Randy Black<mailto:rblack at hillcity.k12.sd.us>
> To:
> terrapreta at bioenergylists.org<mailto:terrapreta at bioenergylists.org>
> Sent: Friday, April 20, 2007 10:13 AM
> Subject: Re: [Terrapreta] Charcoal mix continued
>
>
>
>