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Comments on Methane and Agriculture
by Jim Stewart, PhD

Comments following quotes from text (also attached) 

p. 112-113 presents three major agricultural strategies:
"1. Methane from dairy and livestock has a reduction target of -40%
and is covered in the SLCP strategy." 
However, the reduction target of -40% should be treated as a floor
and not a ceiling. There are many ways to reduce methane from
manure and enteric emissions. 
Methane from manure can be economically and effectively eliminated
by allowing animals to graze in pastures where the manure naturally
aerobically decomposes with zero methane emissions.
Enteric emissions can be reduced in both dairy and livestock by
over 90% by the addition to the feed of only 2% Asparagopsis
seaweed, as described in several publications. [The red macroalgae
Asparagopsis taxiformis is a potent natural antimethanogenic that
reduces methane production during
in vitro fermentation with rumen fluid. Robert D. Kinley, Rocky de
Nys, Matthew J. Vucko, Lorenna Machado and Nigel W. Tomkins. Animal
Production Science, 2016, 56, 282–289 
http://dx.doi.org/10.1071/AN15576 
Identification of bioactives from the red seaweed Asparagopsis
taxiformis that promote antimethanogenic activity in vitro. Lorenna
Machado & Marie Magnusson & Nicholas A. Paul & Robert Kinley &
Rocky de Nys & Nigel Tomkins. J Appl Phycol. 2016.
DOI 10.1007/s10811-016-0830-7 ]

"2. Nitrous oxide resulting from nitrogen fertilizer
applications."
 Must be quantified.

"3. Increased carbon sequestration in soil."
 The methods (such as no till agriculture) must be specified and
the outcome quantified.

Appendix D Pathways says the only reductions in the agriculture
sector are “electric and natural gas efficiency improvements
assumed in the Reference Scenario, consistent with the 2015 IEPR
AAEE building efficiency assumptions described in the section
above. These measures result in a 7% to 15% efficiency
improvement.” 

This tiny reduction is far too small, there are many other ways to
reduce GHG emissions in the agriculture sector, which should be
specified and quantified.