Sustainability: of, relating to, or being a method of harvesting or using a resource so that the resource is not depleted or permanently damaged. – Meriam-Webster Online.
The definition above isn’t wrong, but, it seems to me, it is incomplete, at least when it comes to food (and probably everything else) since it’s too focused on micro-effects as opposed to macro-effects.
Take, for example, the industrial-scale production of crops (such as corn) that we’re used to. It relies on man-made fertilizers, which are produced using petro-chemicals and we’re running out of the “petro-” part of that equation. So it’s not sustainable. Industrial-scale meat production relies on industrial-scale production of corn – also not sustainable. And the use of such products has a broader effect on the environment by contributing to climate change, another un-sustainable cost.
On a recent edition of NPR’s Science Friday Ira Flatow interviewed Christopher Weber, an assistant research professor at Carnegie Mellon University, about a study he and co-author Scott Mathews published in Environmental Science and Technology on whether or not “food-miles” matter. “Food miles” are a way to measure the distance a food travels prior to consumption and the authors were specifically interested in the effects of eating, say, asparagus from Chile in January as opposed to asparagus grown next door in May. In short, what are the effects of “eating local.”
They found that selecting locally grown food had relatively little effect on the impact that you, as a consumer, have on the environment. This study echoes the results of a New Zealand study that found that New Zealand lamb eaten in Great Britain had a lower environmental impact then British lamb eaten in Great Britain.
The Carnegie Mellon study also found that by simply giving up red meat and cheese one day a week and instead eating chicken, fish, or just vegetables you could have a more positive impact than by buying locally grown produce and meat all the time. Sounds simple, eh? You make Tuesday your dedicated chicken or fish night and you help the environment. Sorry, nope.
The study is flawed since it focused on large-scale agriculture. It assumed that my friends the Coles of West Wind Farms used the same methods for raising their cattle as ConAgra does. The Coles meat is grass fed. Their cattle still produce the methane and nitrous oxide (greenhouse gases) that ConAgra’s cows do, but they don’t use commercial fertilizer on their fields, instead they rely on the manure all their animals produce for fertilizer. By doing so they eliminate not only the direct costs of fertilizer for their fields, but also the indirect costs of the fertilizer used to grow grain and the transport costs for the fertilizer and grain.
Or, put more simply, actually determining effects – for better or worse – is incredibly complicated.
And determining effects is even more complicated because more than one area of expertise is involved. The Weber/Mathew study doesn’t even attempt to account for the medical costs of using antibiotics in chickens or beef or the economic effects of hog manure ponds on real estate. In fact, it’s focus was specifically on green-house gases. Important, yes, All-encompassing, no.
I’m not arguing against giving up beef and cheese one day each week nor that doing so won’t have a mild effect if everyone does so, but I would argue against substituting fish for that mac-n-cheese because wild fish stocks are collapsing. The California, Oregon, and Washington salmon seasons were canceled this year because wild salmon stocks are in such bad condition. And I’ll point out that even though chickens and hogs don’t directly produce methane, their manure lagoons do.
The bottom line: choosing to buy from local producers using sustainable agricultural practices will almost certainly have more of a positive effect on the environment, even if that effect is harder to measure, than, say, giving up a cheese burger once a week.