VIA HPI: Source: http://m.bbc.com/news/science-environment-28409704
UNITED STATES, July 21, 2014 (BBC): A new study suggests that the production of beef is around 10 times more damaging to the environment than any other form of livestock. Scientists measured the environment inputs required to produce the main US sources of protein. Beef cattle need 28 times more land and 11 times more irrigation water than pork, poultry, eggs or dairy. The research has been published in the Proceedings of the National Academy of Sciences.
The researchers developed a uniform methodology that they were able to apply to all five livestock categories and to four measures of environmental performance. As a result, beef comes out clearly as the food animal with the biggest environmental impact. As well as the effects on land and water, cattle release five times more greenhouse gas and consume six times more nitrogen than eggs or poultry.
"The overall environmental footprint of beef is particularly large because it combines a low production efficiency with very high volume," said Prof. Mark Sutton, from the UK's Centre for Ecology and Hydrology. "The result is that the researchers estimate that over 60% of the environmental burden of livestock in the US results from beef. Although the exact numbers will be different for Europe (expecting a larger role of dairy), the overall message will be similar: Cattle dominate the livestock footprint of both Europe and US."
Cutting down on beef can have a big environmental impact they say. But the same is not true for all livestock.
"One can reasonably be an environmentally mindful eater, designing one's diet with its environmental impact in mind, while not resorting to exclusive reliance on plant food sources," said Prof Eshel.
"In fact, eliminating beef, and replacing it with relatively efficiency animal-based alternatives such as eggs, can achieve an environmental improvement comparable to switching to plant food source."