Although Lyman never cited a 2006
(or any other authority) for his assertions, it is true that the report blamed 18 percent of global warming on livestock. Four years later, in March 2010, one of the report's authors acknowledged that the number was probably overblown, as in
. More importantly, very little of that 18 percent figure has any connection to well-managed traditional, grass-based animal farming here in the United States. For starters, 48 percent of it is from changes in land use, mostly clearing of forests for grazing and growing feed crops in Brazil, India, Indonesia, Sudan, and other developing countries. The United States, in contrast, is actively reforesting and, according to Cornell University researchers, is not expanding croplands for feed. In U.S. farming, most carbon dioxide actually come from fuel burned for vehicles, equipment, and machinery. Smaller, pasture-based farms in the U.S. have low carbon dioxide emissions because they keep their animals outdoors and use little mechanization.
On his repeated suggestion that meat production means massive nitrous oxide emissions, Lyman was way off base. EPA figures show that nitrous oxide makes up only about 5 percent of all U.S. global warming emissions and that
of American agriculture is linked to just 6 percent of U.S. greenhouse gases. More than three-quarters of agriculture's nitrous oxide emissions result from manmade fertilizers. Thus, raising livestock does not inherently aggravate the problem, because farming that does not feed fertilized cropsâin other words, pasture-based and organic farmingâcauses negligible nitrous oxide emissions. Equally important, the animal manure used on traditional farms actually mitigates the need for commercial (fossil fuel-based) fertilizers.
Finally, just because something generates some global warming emissions doesn't mean it should be categorically condemned. For instance, natural wetlands cause more methane emissions than any single human source, yet wetlands are considered essential water filters and wildlife habitats. No one in his or her right mind advocates getting rid of natural wetlands to lower methane emissions.
results in increased organic matter to the soil"
[italics mine]. Likewise, studies done by the Department of Agriculture and University of Georgia found that soil erosion and water pollution are both greatly reduced when cropland is converted to well-managed pastures for animal grazing.
Additionally, as Pimentel himself frequently notes in his writings, grazing animals put land that is unsuitable for growing crops into food production, an efficient use of natural resources. As the National Sustainable Agriculture Information Service eloquently explains:
Ranchers ... conver[t] sunlight, water, and carbon dioxide into a high-quality human food source. ... [M]ost of the land in the U.S., and indeed in most countries of the world, is not tillable and is considered rangeland, forest, or desert. These ecosystems can be very productive from a plant biomass perspective, but ... are generally non-farmable... However, grassland ecosystems ... produce plant materials that are highly digestible to ruminant animals. ...
This is of particular importance to the sustainability of agricultural production systems because grasslands and rangelands have the capacity to produce millions of tons of this energy source. Grazing of native and introduced forages on grasslands and rangeland thus is a very efficient way of converting otherwise non-digestible energy into forms available for human use: milk, meat, wool and other fibers, and hide.
" [my emphasis]
Aside from these ecological questions, the Lyman v. Niman debate focused on the ethics surrounding meat eating. It is quite impossible, of course, to change the mind of someone who fervently believes that it's immoral to eat meat, and I've never endeavored to do so. (To get the picture, just imagine standing before a large group of zealous pro-lifers trying to explain why you volunteer at a Planned Parenthood clinic). My modest hope for the evening was to make the case that there is more than one way to eat environmentally and ethically.