Agriculture Reference
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mersed in a swamp or bog. 53 The Max Planck in vitro experiments were corroborated by
PF Crutzen, with 18 year old data relating to forest and savannah in Venezuela which had
been puzzling him. 54 This discovery could explain two questions that have perplexed sci-
entists: why strong fields of methane have been observed over tropical forests; and why
methane levels in the atmosphere have not increased as much as expected - the possible
explanation being deforestation. 'Initial extrapolations of this new source' states S Houwel-
ing, another scientist currently examining the matter, 'point to a global source strength of
63-236 million tonnes of methane a year, which is roughly comparable to wetlands (com-
monly considered the largest source of methane).' 55
If this source were confirmed it would suggest that reductions in methane emissions
made by reducing livestock numbers might be partially offset by an increase in plant bio-
mass. However even if methane emissions from cows were completely offset in this way,
there would probably still be a global warming advantage in replacing grazing cows by
forest in many areas with enough rainfall to grow trees, because of the superior ability of
the trees to act as a carbon sink.
In 2008 another department of the FAO reported:
Since 1999 atmospheric methane concentrations have levelled off while the world
population of ruminants has increased at an accelerated rate … Prior to 1999 there was
a strong relationship between change in atmospheric methane concentrations and the
world ruminant populations. However, since 1999 this strong relation has disappeared.
This change in relationship between the atmosphere and ruminant numbers suggests
that the role of ruminants in greenhouse gases may be less significant than originally
thought, with other sources and sinks playing a larger role in global methane account-
ing. 56
The fact is that scientists still do not have a complete idea of how the biological methane
cycle works, and even less idea of what might happen if we removed an entire order of cre-
ation out of the human food chain which now dominates the biosphere. The FAO's figure
of 5.4 per cent represents the maximum possible GHG savings that might be expected from
dispensing with livestock; since it is higher than the EPA's or any other estimate, and since
it takes no account whatsoever of substitute methane emissions from increased cropping or
from wildlife, nor of the uncertainty that surrounds the entire methane budget, I suspect it
is an overestimate, albeit perhaps not a large one.
Carbon Colonialism
 
 
 
 
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