Once again we are plagued with a religious radicalism, forced to endure half-truths and strawmen set up to direct people along a narrow road toward a mis-Utopia masquerading as a logical solution to our woes.
Sure, everyone should choose a path that fulfills their ethical goals and lies in line with their moral compass, and many of our problems today stem from the fact that people neglect the re-assessment and re-evaluation needed to chart such a course. There are a lot of problems in the world, but it's certain that none of them can be solved with vegetarianism as a blanket prescription.
Where does the food that vegetarian's consume come from? Sadly, it generally comes from farmland, and may pause on it's journey to the consumer in a factory for further (no doubt energy intensive) processing, typically to be massaged from it's native state into something more closely resembling meat (eh?)
Isn't vegetarian food grown on the same farms where the plough tears through the field, spewing the denizens of that dark and earthy realm out into the harsh sunlight, killing them indiscriminately? Who actively takes on the karma begotten through this slaughter? What about the effects of the pesticides and fertilisers that the earth is salted with in order to raise yields to economical levels? What about the displaced fauna, the birds, rodents and other mammals small and large?
I don't read of many vegetarians that give these issues much deep thought, and any I've pointed it out to stridently insist that what I do is so much worse. Microbes don't have souls, so it's all good from a vegetarian perspective.
Is it? Any thinking person will agree that grain-fed meat must have a cumulative impact, with the burden of both grain growing and raising animals, but there is nothing natural about this kind of meat production, and certainly nothing redeeming, so I would never think to promote it.
What if one were to eat only pasture fed animals? We have a situation where the animal grazes, the worms and other soil organisms are not killed off, and, to an extent, other mammals can live side-by-side with the stock, and birds are only minimally disturbed, usually when the animal they are perching upon decides to take off across the paddock. It's not always an ideal relationship, the farmer still has to ensure the pastures aren't being consumed more by natives than by our introduced food-on-four-legs, but it's a start.
Let's consider it from a basic energetic perspective.
Let's imagine a field, say 2 hectares, with a DSE (Dry Sheep Equivalent) of 3. A DSE of 3 means that each hectare could support one ewe with lamb. A sensible farmer might run two ewes on this land, each bearing one lamb. As the lambs grow, the ewes drop back to requiring 1 DSE each (for a total of 2) and the lambs might require 1 each as they grow, for a total of 4 DSE, leaving 2 DSE, so effectively this small flock could survive on that land.
This gives us 2 sheep for meat each year. Let's say we grow them up to 36kg to try and make the most meat out of our land. This will give us a cold carcass in the area of 15kg, for a total of 30kg of meat for the year.
Lamb, depending on the cut, might give us about 800kJ of energy per 100g, or
Note It's been rightly pointed out that I've failed to take into account the muscle to bone ratio in the above calculation. 19% was suggested as a reasonable figure, which would reduce our energy to 48,000kJ. But, but, but! We must also consider that the 800kJ of energy is for lean meat, and in a normal diet (mine :-) ) none of the fat escapes the dinner table. Finding nutritional figures for full-fat meat is difficult, but http://www.nal.usda.gov/ tells me that even with 1/8" of fat left on the lamb chop has an energy of 983kJ/100g for 58,980kJ. We're also leaving out a lot of other useful sources of nutrition such as offal and bones so we could reasonably expect a total energy in excess of 100,000kJ when all is said and done. I'll provide a figure of 60,000 above to be mean to my cause.
How would we go if we put this land down to soybeans? With a yield of about 3 tonnes per hectare we would harvest 6 tonnes from this land. Soybeans have an energy content of 1.25kJ per 172g for cooked mature beans. Total energy returned: 43,604kJ! We would exhaust ourselves trying to grow and harvest this crop manually, especially if we had to live only on the energy it provided.
So we get 5.5 times more energy off the land by growing sheep! And that's before we even begin to consider the energy costs of production, and the fact that we haven't had to sterilise the earth to grow our sheep. Let me tell you, if we were doing it all by hand (as we well might be once peak everything kicks in) rounding up a couple of sheep is a lot less energy intensive that harvesting an hectare of grain...
Further to these typical production practices, we can envisage a more advanced system drawing on the practices of permaculture to inform a better way. As far as the smallholder is concerned he or she wants to maximise production of food for family and friends in the face of an uncertain future, one where the spectre of Peak Oil, even Peak Everything, and climate change looms above all plans.
Such a smallholder will not be interested in hand ploughing a field, broadcasting the seed and then scything, gathering and winnowing the crop. Far too much energy would be expended, to the extent that the farmers would starve trying to feed themselves.
Far better to build up an integrated pasture and forest system, whereby various animals can graze (sheep, goats, ducks, chickens) in harmony, maximising meat production beyond the numbers supplied above, as well as providing sideline benefits of vegetative produce.
In essence, grain production is a dead-end path. Once yields come close to the theoretical maximum there is very little that can be done to increase them further, without building your own genetic engineering lab and releasing all kinds of virulent filth upon the earth. Fundamentally, each additional species you introduce to a grain field reduces the overall productivity of your main crop.
Only through a synthesis of animal and plant within the growing area can increased yields be realised. While ever we are stuck in the two dimensional realm of the grain crop true productivity gains cannot be made, and so we cannot hope to live well in an uncertain future. It would seem, given this amateurish analysis, that suggestions we will find humanity's salvation via vegetarianism are misplaced. It's doubtful we'd even find the salvation of a single post-peak oil family. In fact, turning the earth over to grain fields might just make all our problems worse.
If you're hoping to survive peak oil, my advice would be to stick with the mixed agricultural systems that are emblematic of most "primitive" societies, and then whenever you meet someone claiming to have discovered the means to salve all of humanity's ills in one convenient spiritual package you will at least have the energy to run as fast as you can in the opposite direction.
5 comments:
The 15 Kg carcass weight you referenced was for sheep fattened with sugar cane, which is not included in your impact analysis. Otherwise, the carcass weight for the sheep breed mentioned is 9-12 kg (from your reference). Note that carcass weight is muscle, sinew, and bone. The actual muscle to bone ratio of heavy grain-fed sheep is in the 19% range;
http://ajol.info/index.php/sajas/article/viewFile/4059/11908
What muscle to bone ratio are you expecting for grass-fed Martinik sheep (or what ever breed you are thinking of)?
So your comparison has to take into account grass-fed weights and muscle to bone mass ratios.
I started with North Country Cheviot sheep, though have experimented with different breed mixes for wool quality. If raised strictly for meat on pasture, either breed of Cheviot would do quite well.
We also raise chickens on pasture (Orpingtons, New Hampshires, Wyandotes, Leghorns) and are quite pleased with the results. They do require grain supplementation, of course, as pasture only replaces about 30% of their feed requirements. High insect population periods helps to lower the supplement ratio.
I would think that dairy goats/sheep might be another way to go if one were looking for a daily supply of animal-based food (milk, cheese, yogurt,...)
Note that organic no-till greatly reduces the need to furrow/plow/cultivate the land;
http://www.croproller.com/
There were a few issues with using that reference for carcass weights based on slaughter weight, but it was the only one that an admittedly brief search pulled up that gave a relationship between the two. Still, for a slow grown grass fed lamb to 36kg live weight then 15kg is not outside the realm of possibility for a meat breed sheep I would have thought.
If we were to choose not to utilise the bones and offal as food, then a 19% muscle to bone ratio would reduce the numbers for lamb by a fifth, down to 48,000kJ for the lamb. This is then equable to the soybeans, and it becomes a question of input energy to the two systems.
Unfortunately most energy databases only quote for lean lamb cuts, or trimmed to an 1/8" of fat. As most of the energy is in the fat then the quoted energy content is lower than it would be on my plate, because you wouldn't catch me eating a chop trimmed of fat!
http://www.nal.usda.gov/ indicates that a lamb chop trimmed to 1/8" of fat contains 983kJ/100g which pushes our muscle:bone adjusted number closer to 60,000kJ. By leaving out the offal we're also losing a lot of extra energy: 573kJ/100g for the kidneys, 920kJ/100g for the liver for example. Sadly I can only find one reference for broth, and that's for beef too: http://chestofbooks.com/health/nutrition/Dietetics-3/Broth-And-Meat-Jellies.html which gives us a figure of 69kJ/100g, though even that is for a meat broth rather than a bone broth. I'm guessing there would be a moderate amount of energy there given that marrow is a fat.
Once we start to consider the other factors, such as additional products that can be drawn from the land the lamb scenario again starts to pull away from the grain scenario. And of course offal and bones are also sources of energy.
Organic no-till would still require at least 2 passes of the tractor over the land (sowing & harvest) and in considering a future without fuel then that would all need to be manual or animal labour.
In terms of post-peak communities, is time going to be better spent growing grains or growing meat? I think it would be most cost effective to have integrated systems containing meat, rather than fields of grain. Dairy, eggs and other side products would add to the balance in favour of such systems.
Oops, that should be "to a fifth" not "by a fifth" in the second paragraph.
Hi Geoff! It's Samantha from Sydney Peak Oil here. I've been thoroughly enjoying catching up on your blog (I can't imagine why it's taken me this long to stumble across it).
However! You're being a bit harsh on the vegetarians here. I believe your calculation on energy from soybeans is out by a thousand times.
Going by the data you linked to, six tonnes of soybeans produces 43 *million* kJ (not 43 thousand).
(i.e. 172g of soy = 298 calories = 298 x 4.2kJ = 1,250kJ)
By my calculation, that means that the vegetarians are actually ahead by at least 42 million kJ in your scenario - although I certainly accept that sheep can get useful nutrition from marginal land that would never crop 3 tonnes per ha of soy, etc.
Hi Samantha,
It seems that back of the envelope calculations just don't cut it for this kind of thing :-( lol!
It looks as though I've divided the KJ by 1000, so I must have assumed they meant calories rather than Calories.
I'm going to have to revisit that topic when time permits and draw some better conclusions with better numbers!
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