Loosecanon wrote:
> "Terryc" <newsthreespam-spam@[EMAIL PROTECTED]
> wrote in message
> news:47fecd4d$0$18353$c30e37c6@[EMAIL PROTECTED]
>
>>Charlie wrote:
>>....Snip....
>
>
> I concur with the idea that char or charcoal probably have no real
effect at
> all on nutrient supply and if any only a minor part. Charcoal is a good
> substance to grab nasties hence why it is used in water filters but have
to
> be changed regularly too work correctly.
Nope, there is a distinction. Charcoal is basically just carbon with
minerals trapped in it, whereas Char isn't completely energy depleted
and thus has something to add overtime. AFAIUI, you can burn wood char
again, but not charcoal.
> The idea that floodplains were extremely rich and that charcoal or char
was
> found would not be the reason for the fertility. A true floodplain is
> enriched by flooding, nutrient and silt movement along a watercourse.
The problem in the Amazon basin was that it is basically rainforest,
which is extremely good at nutrient scavenging, so much so that the
soils are relatively poor.
I think that there is also the factor that the area for supply of
nutrients, the Andes is comparatively very minor compared to the area of
the basin.
> Here in Australia farmers were encouraged to clear the
> land before claiming it as their own.
I think the word was "required" to clear and it was so much per year if
they wanted to keep it.
> The indigenous folk being hunters and gathers burnt vast tracks of land.
Umm, AFAIK, they didn't burn vast tracts, but rather small plots. Cooler
fires, less nutrient loss.
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