IATP Hog Report - Institute for Agriculture and Trade Policy

Section 4
excluding air from between solid particles and creating anaerobic
conditions that lead to production of gasses such as methane and
ethylene. 58
Nitrous oxide
Nitrous oxide is released from natural processes in the soil, from nitrogen
fertilizer, fossil fuel combustion, animal and human wastes, water bodies,
and biomass burning and land clearing. Nitrous oxide is the least prevalent
of these three gasses, but it is one of the most potent greenhouse gasses. 59
Nitrous oxide has over 200 times the warming effect of carbon dioxide
and lasts 150 years in the atmosphere. However, because it is not
prevalent, it has contributed to only about three percent of the global
warming. Hence, in livestock production, methane and carbon dioxide are
the relevant greenhouse gasses. 60
Potential Solutions
Emission processes suggest that the most significant contribution to
reducing in greenhouse gasses that farmers can make is to change manure
management. 61 This change can be toward more complex and capitalintensive
liquid manure management systems, such as sophisticated
methods of methane collection, solids separation, and biogas production,
or toward more natural management systems such as pasture or solid
manure. Which direction we choose will have implications both on how
well other social goals are met and for the structure of animal agriculture.
The two main gasses emitted in solid manure handling and storage, carbon
dioxide and ammonia, are easily taken up, carbon dioxide by plants and
ammonia by the bedding materials. Solid manure using straw or other
grain-based bedding also replenishes the soil carbon. Solid manure
handling with composting is more labor and management intensive and,
hence, the less costly choice for independent farmers, while the more
capital-intensive systems may be the only option for the largest animal
factories.
At animal factory sites where large amounts of waste are generated,
composting can also produce odorous volatile compounds that create air
pollution and "should be carried out in closed reactors with sufficient
treatment of exhaust air." 62 Bion Environmental Technologies (Part 3.
Building Sewerless Cities) designs, sets up, and operates systems at
animal factory sites that "bioconvert" liquid animal waste into a fertilizer
material called BionSoil. 63 BionSoil is then certified as an organic product
to which Bion Environmental Technologies retains the rights. As of
August 1999, it operates 16 animal waste systems in six states with
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