permaculture

[Lawrence London <lfljvenaura@gmail.com>]

---------- Forwarded message ----------
From: Karl S North <knorth@binghamton.edu>
Date: Mon, Feb 8, 2016 at 6:00 PM
Subject: Re: [SANET-MG] Carbon Sequestration?
To: sanet-mg@googlegroups.com


On Mon, Feb 8, 2016 at 9:24 AM, Elizabeth Henderson <
elizabethhenderson13@gmail.com> wrote:

> This white paper from Jack Kittredge of NOFA-Mass has references.
>
> On Mon, Feb 8, 2016 at 8:24 AM, Dieter <brand.dieter2015@gmail.com> wrote:
>
>> Hi,
>>
>> For the last 10 to 20 years, we have heard about *Carbon Farming* for
>> sequestering carbon in soil. I have heard about *Allan Savory's *claim
>> that his grazing techniques could prevent climate change.
>>
>> Are there any data showing which farming techniques has succeeded in
>> increasing carbon levels in the soil in a permanent way?  For example, for
>> 1) organic farming, 2) grazing and 3) forestry?
>>
>> I realize that any general statement regarding these types of land
>> management is impossible, but are there any data whatsoever?
>>
>> Regards,
>> Dieter
>>
>
​Dieter's question is an excellent one, not just in regard to climate
change but more generally in regard to the quest for more sustainable
agroecosystems. The general thrust of the Kittredge paper is fine, but I
don't see that it goes far to answer Dieter's question, which I would
rephrase as follows: what data are available of how to build soil carbon in
ways that affords the most sustainable agroecosystem design​?

The paper makes good recommendations,  mostly already well known at least
to their practitioners, but it contains little data on long term soil
carbon levels, which would require comparisons of results in long-term
trials of different whole farming systems designed specifically as
maximally healthy agroecosystems. The paper contains a lot of information
about the complexities of soil biochemistry. Eventually that data can be
useful, but that is not what is needed at this point. All we need right now
is outcomes of trials of different system designs as to carbon levels.
These can be simple comparisons of % of soil organic matter - how well it
can be built and sustained over time.

We already have a baseline for the Northeast environment, which is
acknowledged in the Kittredge paper. In worn out, abandoned farmland, the
unmanaged natural ecosystem rebuilds soil organic matter, often from a low
of 1%, to 5-6%, which may take 20  years or more. My direct experience
confirms this, at least as long as field remain relatively open, largely
low-growing perennials.

Then the question becomes how much can management enhance this level and
this rate of regeneration, and what agroecosystems do it best? Dieter
mentions grazing techniques. They are but one essential element in Savory's
grass-ruminant system. And that system is only one potential component or
subsystem in Savory's framework for designing managed ecosystems to sustain
essential ecosystem processes while producing food: the most sustainable
possible farms in a word. My own experience with the grass-ruminant
subsystem over 30 years shows that it can build its own soil carbon to
permanently sustainable levels while producing a surplus to build organic
matter in a cropping subsystem over time as well.

The next important question is the ratio of grass-ruminant acreage needed
to sustain high carbon levels per cropping acre? Cuban agroecologists
recognized the importance of this question early on. Their research showed
that, at least in their tropical climate, a 2:1 ratio is sufficient: two
acres of perennial forage supports enough ruminants to build and maintain
high levels of carbon in both their 2 acres and in one acre of cropland,
assuming all the best practices are used in both - planned grazing, maximal
soil cover, minimal tillage, diversity/rotation, water control, etc.
Although the research has not been done to my knowledge that reveals an
effective ratio for the US Northeast, my own experience farming in that
region suggests that the ratio there is in the same ball park as the Cuban
one.

Moreover, evidence from my experience farming with animals suggests several
interesting conclusions about the potential of the above described
grass-ruminant-and-cropping system:

1. It can usually build and maintain higher levels of soil carbon than the
best-designed cropping system alone;

2. Despite the constant attack from animal rights and vegetarian ideologues
on any kind of livestock in farming, the number of animals necessary to run
this system well  is only a tiny fraction of current livestock production
per capita in rich countries. Universal adoption would mean we would have
to eat a lot less meat (usually a good thing) while using ruminant animals
to maximize agroecosystem health and productivity, provide draft animal
power, contribute small amounts of animal protein to our diet and produce
considerable amounts of leather and fibers from landscapes suitable only
for grazing.

3. Much presently cropped farmland is not flat enough and should not be
cropped unless terraced. The sloped land can support the ruminant component
of the system without stealing acreage that is suitable for cropping.
Sloped land in perennial cover, with proper grazing management, can provide
the ruminant diet of 100% forage (what the species was designed for) while
maintaining and enhancing ecosystem processes that would deteriorate under
any cropping system. Thus the claim that livestock on farms must steal land
from food crops is mistaken.

However, these conclusions are really only hypotheses; they need the kind
of research described above, long term agroecosystem design trials, to test
them. Has anyone done the research? If so, I ask, alone with Dieter, where
is the data?

-- 
Karl North -  http://karlnorth.com/
"Pueblo que canta no morira" - Cuban saying
"They only call it class warfare when we fight back" - Anon.
"My father rode a camel. I drive a car. My son flies a jet-plane. His son
will ride a camel."
 —Saudi saying

-- 
Lawrence F. London
lfljvenaura@gmail.com
https://sites.google.com/site/avantgeared/