I originally posted this as a comment, then thought, well, this is a lot of writing just to be a comment. So here goes:
Eighty percent of corn and soy crops are used for livestock feed, not for vegan food. The problems of grain, soy, and monocultures are simply not ones that can be pinned on the vegan movement. To paraphrase Gary Francione, the problem of designer foods is not inherent to veganism any more than the problem of designer clothes is inherent to wearing clothes. There are plenty of designer foods that meat-eaters eat, and there are plenty of vegans who eat mainly local and organic, plenty of vegans who don’t eat soy or tons of corn and wheat, etc. To claim that all vegans eat all grain and soy, or that a vegan diet only consists of grain and soy, is a disingenuous straw-man argument.
Veganic/stock free permaculture is a thriving practice all over the world. It seems many locavores are willfully ignorant of this fact, and I’m not entirely clear why. Veganic permaculture is by far the most sustainable farming practice. There are many books and internet resources on this if you need more information.
Grass fed livestock don’t partake in the problem of corn and soy feed. But pasture/grass fed animals require more than twice the land of factory farmed animals. Grazing is one of the worst environmental problems that exists. Overgrazing has trampled and compacted land and been the largest contributor to desertification. Two-thirds of the American West, for instance, is grazing land. Clearing land for pasture is the major reason for destruction of forests and biodiversity including the atrocity of rainforest destruction. This is simply not a problem with even the least sustainable plant diets. Even the most industrialized plant diets use exponentially less land per yield than meat diets, especially grazed meat diets. Grazing is one of the most ecologically absurd situations humans have ever created. One researcher, Vacliv Smil, who has done very careful math has estimated that by 2050, if we are to feed the world on a meat diet, we will need 67 percent more land on the earth. Again, there is no comparable number for even the least sustainable plant agriculture, as plant protein is much higher yield per energy input than meat, and is consumed directly instead of being turned into an animal first.
Cows emit massive amounts of methane, one of the worst greenhouse gasses, and it is well documented that this is a major cause of global warming, surpassing all forms of transportation combined. Grass fed and free-range livestock emit many times more methane than industrial livestock, in fact, because they live much longer. Again, this problem is simply not comparable to the problems of plant agriculture. Plants are not farting and stomping us to extinction.
Raising livestock, even grass-fed, is also by far the world’s number one cause of water usage and water pollution. Again, not comparable to the water usage of plant agriculture.
Furthermore, the issue of transportation of food over long distances is often cited by locavores, but the truth is much more complicated. The simple equation of food miles does not account for whether or not irrigation is used, whether or not food is grown in hothouses, whether or not food is in season, how food is stored, how food is cooked, how much food was shipped where and how, whether or not it is animal or plant food, etc. In short, transportation is about ten percent of a food’s energy cost. To quote James McWilliams, who has many problematic ideas but is right-on when it comes to food miles, “To take an extreme example, a shipper sending a truck with 2,000 apples over 2,000 miles would consume the same amount of fuel per apple as a local farmer who takes a pickup 50 miles to sell 50 apples at his stall at the green market.” Furthermore, simplistic food mile equations do not account for people who live in regions where food is not available, which opens up a sizeable, incredibly complicated can of worms in terms of human rights and food access. The local ethic, despite its benefits, simply does not take responsibility for the problem of food access in a globalized world where food is an inherently global issue. I am not saying I have a perfect answer to this problem, but I am saying that food access in a globalized world is complicated, and it deserves to be dealt with in a complicated way, especially if people who have social and economic privilege are claiming to be concerned with human rights.
But I digress. I don’t at all mean to tear local agriculture a new asshole. There are many reasons to eat local, especially in places where, unlike the Arizona desert where local food–including all meat–is all sustained by irrigation, local makes sense. I support eating local for several reasons, and I eat local as much as I can (and I’m a vegan… gasp). The point, rather, is that just because something is local does not mean it is the most environmentally friendly option. A life-cycle assessment (LCA) is a much more honest and comprehensive way than food miles to figure which food is the most sustainable.
If you are going to eat animal food, grass-fed meat from permaculture farms is the most sustainable way to do it. But veganic permaculture is exponentially more sustainable due to the minimized effects it has on land, water, and greenhouse gas emissions. Many of the less sustainable techniques of plant agriculture are more sustainable than the most sustainable forms of animal agriculture.
And this does not begin to get into the issue of the rights and interests of individual animals. I happen to believe that an egalitarian and ecologically friendly world is not possible when our personal and mass psychology is imbued with the idea that it is okay to unnecessarily use most of the world’s sentient creatures as mere instruments to our own ends. But that aside, I do understand the issue of animal rights lives in complicated philosophical, emotional, and spiritual territory. However, the issue of whether or not eating meat is good for the environment, especially in the long run, is quite simple: it isn’t. And there are viable, thriving alternatives. We might not like them because they challenge our deep-rooted food habits and assumptions, but within this generation there will be 10 billion people in the world, and save hitherto unknown technological interventions, there won’t even be any more land for meat-heavy diets.