[Terrapreta] Locations of TP soils sites in the Amazon.

[Sean K. Barry]

Hi Kevin,

Yes, there is a map actually.  I'm sure there is a URL for this map available on the 'terrapretalist' site.  Tom Miles can probably show you the link to it.  Or, Lou Gold could, I think, too.  The map may not be entirely inclusive of all sites, either.  But it does show a large total area in many scattered sites.  Many of the sites identified as Terra Preta soils sites include copious amounts of fired clay chunks.  The existence of these chunks of fired clay (what some "pottery shards") in the soil with charcoal are one of the principle elements in the TP soils (along with fish bones and other extraordinary artifacts in the soil) which served to make the theory of anthropogenic development of these soils.

With charcoal, the fired clay chunks and other artifacts are found in some places to depths of up to two meters.  I do not know that all TP soils had fired clay.  There are also some sites containing lighter soils called Terra Mullata (or Terra Mulata, or Mulatta), which have less charcoal and also do not contain fired clay (I don't think so, anyways).  I thought that these sites, too, were determined to be man made in origin, because of their shape and proximity to other known TP sites.

I do not think Black Earth soils occur naturally in the Amazon River basin.  It rains far too much for that.  Any remaining soil organic matter is rapidly decomposed in the heat and moisture.  Almost all of the organic matter there in the Amazon is in the stands of plants on top of the soil.  The root systems of the plants are very shallow. The soils are almost sterile and they tend to be acidic and tight.  Doing any agriculture requires amendments into the soil.  Most soils are washed nearly daily by the rains and the nutrients and SOM are washed away into streams and the river, and/or the soils are heavily leached (nutrients drain down with water below the rhizosphere).   The soils are mostly clays; Aluminum oxides, Acrisols, Oxisols, Ferrasols, and Aridisols (<-Lord protect me from my critics, if I got any of those soil topological names wrong).

Typos are my damned fault ... and not my damned fault, Kurt!  

Regards,

SKB
  ----- Original Message ----- 
  From: Kevin Chisholm<mailto:kchisholm at ca.inter.net> 
  To: Sean K. Barry<mailto:sean.barry at juno.com> 
  Cc: 'Kurt Treutlein'<mailto:rukurt at westnet.com.au> ; 'terra pretta group'<mailto:terrapreta at bioenergylists.org> ; MFH<mailto:mfh01 at bigpond.net.au> 
  Sent: Wednesday, May 28, 2008 10:17 PM
  Subject: Re: [Terrapreta] Old native earth ovens.


  Dear Sean

  Sean K. Barry wrote:
  > ...del...
  >  
  > The Terra Preta found in the Amazon River basin was on a very large 
  > scale.  They had to actively and continuously be producing charcoal 
  > for many many years, perhaps centuries to have covered the area and 
  > the depths they covered with TP soils there, I think. 

  Has anyone ever counted up teh number of known Terra Preta Sites and 
  determined their average area, to be able to estimate the actual area of 
  Brazil that is covered by man-made Terra Preta?

  Black Earth Soils occur naturally in nature. I have heard figures like 
  "The area of Terra Preta in Brazil is about the same area as France." 
  What percentage of teh Black Earth Soils in Brazil are naturally made 
  and what percentage of tehm are actually man-made?


  > What these Tolais people may have been similar, but I suspect making 
  > Amazon style TP soils would take quite a long time.  Its just a 
  > thought though.  Maybe the effect could be made to happen overnight or 
  > in a single growing season with one application of the "right stuff", 
  > too.  Who knows?

  What would be the necessary features of a Black Earth Soil that would 
  differentiate it from a man-made Terra Preta Soil?
  >  
  > One time some one mentioned that the only hard stone like anything 
  > that can be found in the Amazon River basin is fired clay.  And, fired 
  > clay does not wash way like the clay mud does.  I'm thinking that 
  > keeping precious charcoal and garden soil from washing away in the 
  > almost daily rains of the Amazon rainforest was pretty important.  
  > They built dike and swales, too, it seems.  So, I kind of thought that 
  > the fired clay in the TP soils was there just to keep it from washing 
  > away.

  Is the presence of fired clay a necessary feature of a soil, for it to 
  be termed a "Terra Preta Soil?"

  Thanks.

  Kevin
  >  
  > Regards,
  >  
  > SKB
  >  



____________________________________________________________
Take a perfect family vacation to Orlando. Click Here.
http://thirdpartyoffers.juno.com/TGL2141/fc/Ioyw6i3nK7ufykM1ywQesPdIurcLJ7HYFn0ecI25UkxH2uc3dz1YtL/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: /attachments/20080528/b9b0d2ad/attachment.html 
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: image/gif
Size: 257 bytes
Desc: not available
Url : /attachments/20080528/b9b0d2ad/attachment.gif