You might sometimes hear the words “agricultural sustainability” tossed around during a conversation that mentions organic food production as a sustainable answer in feeding the globe’s rapidly expanding population.
For some, it might be more than a little confusing defining just exactly what sustainability is, and how to use this measure to determine if organic food production has a sustainable advantage over conventional methods utilized in today’s modern farming practices.
Perhaps one of the best definitions of agricultural sustainability comes from Dr. John E. Ikerd, Extension professor at the University of Missouri, who offered up this gem:
“An agriculture that uses up or degrades its natural resource base, or pollutes the natural environment, eventually will lose its ability to produce … a sustainable agriculture must be all three – ecologically sound, economically viable and socially responsible. And the three must be in harmony.”
The organic movement has been trying to claim the mantle for sustainability for a long time, but it is extremely limited from many key components. Now, don’t get me wrong. Let me state unequivocally that I’m not saying organic farming is bad — far from it. There are some definite upsides and benefits that come from many organic farming methods. For example, the efforts of organic farmers to move away from monocultures, where crops are farmed in single-species plots, are fantastic; crop rotations and mixed planting are much better for the soil and environment. My goal in this article isn’t to bash organic farms. Instead, it’s to bust the modern myth that organic food production is “more sustainable” in the long run than conventional crop production techniques – which I will prove simply is not the case. Both methods have their individual value in feeding an ever increasing global population.
So let’s get started. A good article came out recently documenting higher groundwater contamination with nitrates under organic greenhouses because they can’t “spoon feed” fertilizer through the drip and depend on compost for which the release is not matched with plant uptake. This has always be a theoretical limitation for organic.
The article titled “Nitrate leaching from intensive organic farms to groundwater” was written by a handful of soil scientists and appeared in Hydrology and Earth System Sciences. It highlighted this specific finding: “Surprisingly, intensive organic agriculture relying on solid organic matter, such as composted manure that is implemented in the soil prior to planting as the sole fertilizer, resulted in significant down-leaching of nitrate through the vadose zone to the groundwater.” (The vadose zone is the part of earth between the land surface and the position at which the groundwater is at atmospheric pressure.) Elevated nitrate levels in groundwater are hardly a mark of “sustainability.”
Organic ecological cost
Additionally, researchers affiliated with the Institute of Organic Agriculture in Switzerland and the Institute of Agricultural Sciences in Germany published a meta-study in which they conclude that organic farming methods lead to higher rates of carbon sequestration in soils. This work was published in a well respected journal, Proceedings of National Academy of Sciences.
Building up soil carbon is a very good thing to do, and organic methods were the state-of-the-art method for doing that from around the 1920s to the 1960s. However, there are now newer and better ways to improve soil quality on farms, and they don’t have the huge carbon footprint problem that is so common with organic – emissions of the potent greenhouse gases methane and nitrous oxide which have 21 and 295 times as much greenhouse gas effect as carbon dioxide respectively.
All forms of farming including organic can lead to soil emissions of these gases, particularly the nitrous oxide. The glaring issue that is problematic for organic is the emissions of those gases associated with composting. Most people might think of composting as a very “green” thing to do, but few realize that composting actually generates a significant amount of these harmful greenhouse gases.
Which brings us to perhaps the key point as to why organic food production isn’t in and of itself “sustainable.” The fact that organic farming isn’t more green than conventional is that while it might be better for local environments on the small scale, organic farms produce far less food per unit than conventional ones. Organic farms produce around 80 percent of what the same size conventional farm produces (some studies place organic yields below 50 percent of those of conventional farms.)
Just the facts
The unfortunate truth is that until organic farming can rival the production output of conventional farming, its ecological cost due to the need for more cropland is devastating.
This shortfall of reduced organic crop yields is driven by limited pesticide options, difficulties in meeting peak fertilizer demand, and in some cases by not being able to use biotech traits. If organic production were used for a significant portion of crop production, these lower yields would increase the pressure for new land-use conversion – a serious environmental issue because of the biodiversity and greenhouse ramifications.
Another consideration regarding organic production is that the best approach to building soil quality is minimizing soil disturbance (e.g. no plowing or tilling) combined with the use of cover crops. Such farming systems have multiple environmental advantages, particularly with respect to limited erosion and nutrient movement into water. Organic growers frequently do plant cover crops, but without effective herbicides, they tend to rely on tillage for weed control. There are efforts under way to find a way to do organic no-till, but they are really not scalable.
Now, turning to genetically modified organisms (GMOs). GMOs have the potential to increase crop yields, enhance nutritious value, and generally improve farming practices while reducing the need for synthetic chemicals – which is exactly what organic farming seeks to do.
At this moment, there are sweet potatoes being engineered to be resistant to a virus that currently decimates the African harvest annually, which could feed millions of some of the poorest nations on the globe. Scientists have created carrots high in calcium to battle osteoperois, and tomatoes high in antioxidants. Also, potatoes are being modified so that they do not produce high concentrations of toxic glycoalkaloids, and nuts are being engineered to lack the proteins which cause allergic reactions in some people. Perhaps even more amazingly, bananas are being designed to produce vaccines against hepatitis B, allowing vaccination to occur where it’s otherwise too expensive or difficult to be administered.
While the benefits of these plants could improve the daily lives of millions of human beings across our planet, there are those detractors who ignorantly refer to them as “Frankenfoods” – unnatural and unsafe, that should be replaced with organic foods.
So, here’s the bottom line. While “only natural” may be appealing as a marketing message, it is certainly not the best guide on sustainability for how to farm with minimal environmental impact. Between rigorous, science-based research and regulation, public and private investments in new technology development and farmer innovation, modern agriculture has been achieving remarkable environmental progress and will continue to be sustainable. To continue to be successful, we need to encourage both systems relying on facts, and not denigrating one system to market another.