[Terrapreta] Interesting article

[folke Günther]

Now, I have made a short recapitulation of this in my
blog<http://folkegunther.blogspot.com/>
FG

2008/5/5 folke Günther <folkeg at gmail.com>:

> Now, I have received the full article and a supplement describing the
> investigation method (attached). Actually, nothing changes my conclusions
> from yesterday; The inevitable decomposition of litter is hastened by the
> addition of charcoal, but since this would happen anyway, *the conclusion
> that the addition of char to soil could be offset by the increased
> decomposition of litter, is wrong.*
> FG
> 2008/5/4 folke Günther <folkeg at gmail.com>:
>
> > I haven't received the pdf yet, but since there as been quite a
> > discussion,I will go through the background. When I have got the pdf, I will
> > go through it and give some more details.
> > The basic is this:
> >
> >    1. *Burying charcoal in the soil always sequesters carbon (carbon
> >    dioxide) from the atmosphere*
> >       - This is true disregarding the route this charcoal may have
> >       taken to the soil. I.e. even if the 'footprint' of this special  charcoal is
> >       larger than its actual content of coal (say that it is flown around the
> >       world), burying the charcoal mean that this certain amount is eliminated fro
> >       the atmosphere.
> >       -  I.e. If you burn it, it will return to the atmosphere, If
> >       you bury it, it will stay in the soil for thousands of years
> >       *
> >       *
> >    2. *Charcoal increase soil metabolism.*
> >    - This may not come as a surprise to any of the members of this
> >       list.The reasons for that, and its effects, have been discussed, and easily
> >       observed, for a long time.
> >    3. *If you mix litter and charcoal, the litter will decompose
> >    faster than if it is not mixed with charcoal.*
> >       - This was confirmed by the study. A large part (25% i the
> >       first two years) of the litter was metabolised by the microorganisms. I do
> >       not know if a simultaneous increase of the plants living in, on or near the
> >       bags was observed. One could expect  that.
> >       4. *In bags with only litter, some metabolism would be
> >    observed, although smaller than in the litter mixed with charcoal.
> >    *
> >       - This is perfectly normal.
> >    5. *Thus, the presence of charcoal increase the rate of litter
> >    decomposition.*
> >       - Why am I not surprised?
> >    - Jumping to the conclusion, however, that the presence of
> >       charcoal in the soil would be offset by the increased metabolism of litter,
> >       is wrong. After a century or two, *all the litter would be
> >       expected to be metabolised,* *charcoal or not*.
> >    6. Therefore, the sequestration effect of charcoal is *not *counteracted
> >    by increased soil metabolism, since the SOM (Soil Organic Matter) is
> >    ephemeral in comparison to the charcoal, and will decompose anyhow. However,
> >    the in increased metabolism is reflected in a change in litter decomposition
> >    rate.
> >
> > It would be very interesting to have the real figures, since that might
> > allow a calculation of the metabolism increase. A friend observed a
> > surprisingly high increase in the decomposition of a small compost heap when
> > charcoal was added
> >
> >
> > 2008/5/2 folke Günther <folkeg at gmail.com>:
> >
> > > In the latest number of Sciene, (2 May), David Wardle, Marie-Charlotte
> > > Nilsson och Olle Zackrisson delivers an article: "Fire-Derived Charcoal
> > > Causes Loss of Forest Humus", where they claim that charcoal particles
> > > remaining after fire increase the microbial activity so they break down
> > > humic particles at a rate that counteracts the carbon sequestration effect
> > > of the carbon.
> > >
> > >
> > ----------------------------------------
> > Folke Günther
> > Kollegievägen 19
> > 224 73 Lund
> > Sweden
> > Phone: +46 (0)46 141429
> > Cell: +46 (0)709 710306
> > URL: http://www.holon.se/folke
> > BLOG: http://folkegunther.blogspot.com/
> >
>
>
>


-- 
NB :Send your mails to folkeg at gmail.com, not to holon.se
----------------------------------------
Folke Günther
Kollegievägen 19
224 73 Lund
Sweden
Phone: +46 (0)46 141429
Cell: +46 (0)709 710306
URL: http://www.holon.se/folke
BLOG: http://folkegunther.blogspot.com/
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