List with ccs
Inserted response comments below.
> On Jan 20, 2016, at 7:38 PM, aryt alasti <[email protected]> wrote:
>
> I do very much so believe that there is huge potential for enhancing
> soil-sequestration capacities globally. Prof. Smith indicates that ultimately
> capacity is maxed out, so that measure to increase would be transitional in
> nature.
>
[RWL1: We can probably all agree that there is an upper limit to how
much biochar can be placed in soil (and the char-caused above ground carbon
out-year increments as well). But some of us think that there is plenty of
room to increase today’s (in-soil total) 2000-2500 Gt C by the 15-20% we need
to remove from the atmosphere.
And there is a guaranteed long-term slow release of that biochar-carbon
- so I can agree with your term “transitional”. But I don’t believe either the
total C or the loss rate are serious limitations for CDR via biochar - nor that
Prof. Smith has indicated so.
> Allan Savory believes otherwise, but I don’t support his master plan as being
> feasible or ethical, which is a long story.
>
[RWL2: This observation relates to my previous point #3 (not repeated
here) - related to Prof. Smith’s most recent article on SCS - Soil Carbon
Sequestration. I’m not sure what Aryt’s concern is with Mr. Savory’s Holistic
Management (HM) advocacy calling for more cattle. My concern is with enteric
methane release - but that is too big a topic to enter here.
> There are a lot of potential factors which don't receive attention when the
> topic of soil carbon is covered. For instance, invasive or migrating plants
> bring new fungal symbionts to soil, which process carbon.
>
[RWL3: The problem of new fungal symbionts is something I haven’t
heard anything about re biochar. But invasive species are a global problem -
and biochar production is one way to justify the expense of clearing them out
(as in several past bills in the US Congress and being practiced already in at
least Nepal).
> And check this out:
>
> http://
> <http://www.serc.si.edu/labs/molecular_ecology/earthworms.aspx>www.serc.si.edu
>
> <http://www.serc.si.edu/labs/molecular_ecology/earthworms.aspx>/labs/molecular_ecology/
>
> <http://www.serc.si.edu/labs/molecular_ecology/earthworms.aspx>earthworms.aspx
> <http://www.serc.si.edu/labs/molecular_ecology/earthworms.aspx>
>
RWL4: There are plenty of articles on the earthworm-biochar
relationship; both favorable and unfavorable. The pre-planning should include
this issue. Biochar can have a wide range of pH and water-holding
characteristics - that can impact how worms respond. An issue - but not a show
stopper I believe.
> The Food and Agriculture Organization claims that:
>
> Soils can sequester around 20 PgC (petagrams of carbon) in 25 years, more
> than 10 percent of the greenhouse gas emissions caused by humans.
>
> Aryt
[RWL5: I found this last statement to be an exact quote (#2) at
http://www.fao.org/zhc/detail-events/en/c/345543/
<http://www.fao.org/zhc/detail-events/en/c/345543/> . The FAO value of 10% at
first sounded low to me - but in fact may be more aggressive than most - when
tied to the term “25 years”. To show this - consider wedges as developed by
Pacala and Socolow
https://www.princeton.edu/mae/people/faculty/socolow/Science-2004-SW-1100103-PAPER-AND-SOM.pdf
<https://www.princeton.edu/mae/people/faculty/socolow/Science-2004-SW-1100103-PAPER-AND-SOM.pdf>
Assuming a continuation for the 50 year period recommended by Pacala
and Socolow and one wedge sequestering 25 Gt C, my computations show that this
FAO soil contribution would be 3.2 wedges with an annual rate in year 50 of 3.2
Gt C/yr by which time 80 Gt C would have been removed. If the majority of this
soil sequestration is via biochar, all these numerical values can be augmented
due to out-year benefits. I doubt that the FAO considered ocean biomass, so
the number could be well on its way to handling all our heritage carbon - not
just 20 or 80 Gt C. The growth problem of course is much more complicated
than the linearity expressed by a wedge - but not impossible.
In following this “Socolow” part of this thread, I saw much of CDR
value at and near this site (http://cmi.princeton.edu/wedges/forestation.php)
also associated with Prof. Socolow. Of his four types of wedges, only the
biomass versions are shown as (CDR-type) sinks.
[RWL6: I am not claiming that the FAO was thinking in wedge terms; I
could find nothing on how the FAO International-Year team came to the above 20
Pg C in 25 years. There is plenty on biochar at FAO sites, but their very
recent handling of the year 2015 as an International Soil Year certainly was
not tied in well with COP21 and wedges.
The acronym “zhc” at this above FAO site (which handled the
international soil year) stands for “Zero Hunger Challenge”. The claim is made
there that we need about $160 per poor person per year to alleviate hunger. I
believe a small portion of that toward biochar would go a long way on the
hunger side - and would then (at no extra cost) do a lot for sequestration.
Here is an example of one of the 600+ biochar cites I today found in
the FAO library:
http://www.fao.org/fileadmin/templates/rap/files/meetings/2011/110602_potential.pdf
<http://www.fao.org/fileadmin/templates/rap/files/meetings/2011/110602_potential.pdf>
. It is not widely known that the Japanese were the world leaders in biochar
until the last decade or so.
So congratulations to FAO for the good soil-CDR work they do. And
thanks to Aryt for his second follow-up comments.
Ron
ps The following kept by Aryt from my message of 18 Jan- with an
exchange under this thread that started on 11 Jan, with a response by Prof.
Smith the next day - along with his attachment of his very recent SCS-biochar
paper.
>
>
> Aryt and list: one added cc; also changing thread title back to the one
> where Prof. Smith has already contributed.
>
> 1. Thanks for your lead yesterday to an important related biomass-soil
> paper (chapter title: “Soaking up the Carbon”) by Professor Smith (courtesy
> cc). I
<snip>
> Again - thanks for the additional Smith paper.
>
> Ron
>
>
>
>> On Jan 17, 2016, at 1:23 AM, aryt alasti <[email protected]
>> <mailto:[email protected]>> wrote:
>>
>> Here's an interesting summarization on the subject by Smith, from a few
>> years ago:
>>
>> https://scholar.google.com/citations?view_op=view_citation&hl=en&user=7P9W6pYAAAAJ&cstart=360&citation_for_view=7P9W6pYAAAAJ:N5tVd3kTz84C
>>
>> <https://scholar.google.com/citations?view_op=view_citation&hl=en&user=7P9W6pYAAAAJ&cstart=360&citation_for_view=7P9W6pYAAAAJ:N5tVd3kTz84C>
>> Aryt
>>
>> On Jan 16, 2016 5:36 PM, "Ronal W. Larson" <[email protected]
>> <mailto:[email protected]>> wrote:
>> Andrew and list:
<snip - rest not needed >
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