This is both very interesting and a tough question.
I do not think the comparison can be made directly.
While industrial livestock production is more efficient (see
nloewen's answer in terms of space, some pollution indicators and water consumption, it is less sustainable / not sustainable.
While small animal farming is less efficient, it is more sustainable and also helps people reducing meat intake (higher prices, you cannot possible have all the required land just for small farms and still maintain the same production volume etc.)
Conclusion: Considering all criteria, small scale farming is clearly more sustainable than industrial farming which also encourages an exaggerated consumption of meat that is beyond recommended values by artificial low prices (maintained through subsidies, not covering for environmental effects etc.).
I will add references and more details in the long answer.
According to this article, there are many aspects that make industrial farming more harmful than small scale:
- health issues: overuse of antibiotics
- environmental issues: overapplication of manure can lead to contamination of water
- animal waste issues: there is too much manure concentrated in one area for the land to handle, manure storage emits gases such as
ammonia, hydrogen sulfide, and methane. These gases can cause noxious
odours, as well as a suite of health problems
- water waste: industrial operations use huge amounts of water for liquefying manure, flushing barns, and drinking water for animals
- soil issues: excess nitrogen and phosphorous left behind can not only alter soil characteristics, and thus productivity, but also run
off into nearby streams and rivers and affect water supplies
- fuel issues: intensive livestock production contributes 80% of agriculture’s greenhouse gas emissions
- transportation issues: industrial-scale livestock production is usually centralized and therefore requires extensive transportation;
as the distance food travels increases, so does the role of chemicals
and processing to reduce spoilage before the food reaches the
- worker issues: workers are inside the barn where air quality is at its worst. Among the most serious hazards faced by workers is
routine exposure to dust and gases emitted from sources of concentrated manure.
This article deals with Agricultural sustainability and intensive production practices. While intensive agriculture practices sustainability is not clear
Large-scale facilities are economically competitive because of
production efficiencies73, but have health and environmental costs
that must be better quantified to assess their potential role in
, small farms have a higher potential of sustainability:
ruminant production on grasslands takes advantage of the high
efficiency of ruminant guts to convert low-quality forage into
high-protein human foods, including dairy products and beef. When
appropriately stocked and managed, grassland–ruminant ecosystems are
an efficient, sustainable method of producing high-quality protein
with minimal environmental impacts.
This article explains why the actual cost of industrial meat production is artificially low and provides a possible solution towards sustainability:
Public policies that encourage a shift toward a more plant-based diet could bolster individual actions in this area. These policies should include preventing factory farms from polluting and requiring them to pay cleanup costs when they do pollute. Without such policies, the products of factory farms will continue to be artificially cheap, in that prices will not reflect their impact on the environment, human health, animal welfare, or the economic and social stability of rural communities. Both the individual and collective actions described above would hasten the shift toward a more sustainable agriculture, which is an important component in the larger transition to a sustainable economy.
One personal act that can have a profound impact on these issues is reducing meat consumption. To produce 1 pound of feedlot beef requires about 2,400 gallons of water and 7 pounds of grain (42). Considering that the average American consumes 97 pounds of beef (and 273 pounds of meat in all) each year,
even modest reductions in meat consumption in such a culture would substantially reduce the burden on our natural resources.
This article deals with the debate about sustainability of small farms vs. industrial farming.
Grass-grazing cows emit considerably more methane than grain-fed cows.
Pastured organic chickens have a 20 percent greater impact on global
warming. It requires 2 to 20 acres to raise a cow on grass. If we
raised all the cows in the United States on grass (all 100 million of
them), cattle would require (using the figure of 10 acres per cow)
almost half the country’s land (and this figure excludes space needed
for pastured chicken and pigs). A tract of land just larger than
France has been carved out of the Brazilian rain forest and turned
over to grazing cattle. Nothing about this is sustainable.
Unfortunately, the article does not provide any references, so its content is arguable. But it is clear that small/organic farming requires much more space than industrial one, giving the same amount of meat is produced. However, we do not have to reach this space usage: if small/organic farming is used more and industrial farming is forced to play "fair", the meat production volume will get lower.
So, in real terms, small farming cannot possible reach the volume of industrial farming, thus generating less environment harmful effects.