Yeah but, WZ, the vast majority of meat consumed by Westerners IS IN REALITY grain-fed. And I am under the impression that there is quite-clearly insufficient grassland available to feed the world's population the amount of meat they eat NOW, let alone if they ate the amount of meat you yourself eat and promote.
"we've been using the wrong comparison to judge the efficiency of meat production.
Instead of citing a simple conversion rate of feed into meat, we should be comparing the amount of land required to grow meat with the land needed to grow plant products of the same nutritional value to humans. The results are radically different.
If pigs are fed on residues and waste, and cattle on straw, stovers and grass from fallows and rangelands food for which humans don't compete meat becomes a very efficient means of food production. Even though it is tilted by the profligate use of grain in rich countries,
the global average conversion ratio of useful plant food to useful meat is not the 5:1 or 10:1 cited by almost everyone, but less than 2:1. If we stopped feeding edible grain to animals, we could still produce around half the current global meat supply with no loss to human nutrition: in fact it's a significant net gain.
It's the second half the stuffing of animals with grain to boost meat and milk consumption, mostly in the rich world which reduces the total food supply. Cut this portion out and you would create an increase in available food which could support 1.3 billion people. Fairlie argues we could afford to use a small amount of grain for feeding livestock, allowing animals to mop up grain surpluses in good years and slaughtering them in lean ones. This would allow us to consume a bit more than half the world's current volume of animal products, which means a good deal less than in the average western diet.
He goes on to butcher a herd of sacred cows. Like many greens I have thoughtlessly repeated the claim that it requires 100,000 litres of water to produce every kilogram of beef. Fairlie shows that this figure is wrong by around three orders of magnitude. It arose from the absurd assumption that every drop of water that falls on a pasture disappears into the animals that graze it, never to re-emerge. A ridiculous amount of fossil water is used to feed cattle on irrigated crops in California, but this is a stark exception.
Similarly daft assumptions underlie the UN Food and Agriculture Organisation's famous claim that livestock are responsible for 18% of the world's greenhouse gas emissions, a higher proportion than transport. Fairlie shows that it made a number of basic mistakes. It attributes all deforestation that culminates in cattle ranching in the Amazon to cattle: in reality it is mostly driven by land speculation and logging. It muddles up one-off emissions from deforestation with ongoing pollution. It makes similar boobs in its nitrous oxide and methane accounts, confusing gross and net production. (Conversely, the organisation greatly underestimates fossil fuel consumption by intensive farming: its report seems to have been informed by a powerful bias against extensive livestock keeping.)
Overall, Fairlie estimates that farmed animals produce about 10% of the world's emissions: still too much, but a good deal less than transport. He also shows that
many vegetable oils have a bigger footprint than animal fats, and reminds us that even vegan farming necessitates the large-scale killing or ecological exclusion of animals: in this case pests. On the other hand, he slaughters the claims made by some livestock farmers about the soil carbon they can lock away.
The meat-producing system Fairlie advocates differs sharply from the one now practised in the rich world: low energy, low waste, just, diverse, small-scale."
http://www.guardian.co.uk/commentisfree/2010/sep/06/meat-production-veganism-deforestation
Another thing to keep in mind, you don't have to have a nice, flat plowed stretch of land that can have huge machinery run over it in straight rows to grow pasture. Hilly, rocky land totally unsuitable for growing wheat easily grows the grass the cows would rather be eating in the first place.
Monoculture and factory farming IS unsustainable. Meat production when used as part of an integrated system is not only sustainable, but beneficial to animals and people.
"It is a claim that could put a dent in the green credentials of vegetarians: Meat-free diets can be bad for the planet. Environmental activists and vegetarians have long taken pleasure in telling those who enjoy a steak that livestock farming is a major source of harmful greenhouse gases.
But research has shown that giving up meat may not be as green as it seems. The Cranfield University study found that switching from British-bred beef and lamb to meat substitutes imported from abroad such as tofu and Quorn would increase the amount of land cultivated, raising the risk of forests being destroyed.
Production methods for meat substitutes can be energy intensive and the final products tend to be highly processed, the report, which was commissioned by the environmental group WWF, found. The researchers concluded: A switch from beef and milk to highly refined livestock product analogues such as tofu could actually increase the quantity of arable land needed to supply the UK."
Read more:
http://www.dailymail.co.uk/health/a...rm-environment-eating-meat.html#ixzz1EcmSaF5s