Recently, two (unconnected) facebook friends posted interesting articles on the possibility of sustainable agriculture at an industrial scale. By now, it is assumed that most know or have at least heard that there are too many people on this planet to continue to support our consumption and we should be doing something about it. How we choose to act and what – if anything – we choose to do can solicit many differing answers and opinions which is why I found it to be such a happy coincidence to find two related links on a social networking site about the Marsden Farm of Iowa State University.
The above link is to the peer-reviewed paper in the PLOS One journal, however, the articles I first read about the study appeared in Mark Bittman’s New York Times column and Wired magazine. The former article, is in a section of the NYT that is called “Opinionator”, and true to its name, Mark Bittman writes about what he knows best which is: food and how you should be eating it. In contrast, Wired, while it does cover a wide range of news about science, would probably be classified as more of a geeky tech publication. But both immediately zero in on the major finding of the study: that a large scale and highly productive form of agriculture is possible with studied and involved techniques rather than continuing the current methods of industrial farming.
To briefly summarize the methods and results of the research (I would recommend reading the paper for more in-depth information and discussion), over the course of 8 years there were four rotation types tested :
- 2 year rotation between crops of maize and soybean. Similar to adjacent commercial farms with adopting the same herbicide and fertilizer used on said farms.
- 3 year rotation between crops of: maize, soybean, small grain (either triticale or oat), and red clover. Reduced nitrogen fertilizer and herbicide applications with occasional cattle manure compost input.
- 4 year rotation between crops of: maize, soybean, small grain (either triticale or oat), and alfalfa-alfalfa. Same nutrient and herbicide inputs as 3 year rotation.
The parameters tested and indicators are well captured in the spider-graph from the PLOS One paper below:
Even with comparably significantly less use of herbicide and fertilizer than the current conventional industrial methods of farming (i.e., the 2 year rotation), the longer rotations show similar weed decline, profit levels, as well as, biomass harvest and yields. In contrast, the longer rotations reduced toxicity potential for surrounding freshwater sources and reduced fossil fuel inputs needed, which are both very outcomes in terms of reducing potential negative effects on the environment from farming and maintaining ecosystem services. The final indicator which was monitored was labor, which shows that longer rotations required more inputs as management was more involved and intensive with the potential to increase opportunities for employment.
Based on these results the NYT blog has heralded this as the “most important agricultural study of year” with “no downside”. I, too, agree that there really doesn’t appear to be any reason not to adopt these methods of farming. However, I wonder about feeding ruminants alfalfa-alfalfa and red clover. Legumes fix nitrogen in the soil and play an important role in plant growth. Would using the livestock perhaps negate or increase net green house gas emissions (I’m thinking of methane’s particularly potent effect) that are initially reduced from less mechanical use for 3 and 4 year rotations?
Even though USDA is a funder of study, Bittman is correct to point out that the higher echelons of the Department may not have even heard of results. Unfortunately, lobbying seems to be a major factor in decision making in both the USDA and FDA which do not necessarily benefit the health of consumers or the environment. On a different note, though, perhaps it’s not a completely fair assessment to say that integrated farming with more crop rotations isn’t being employed because “farmers haven’t heard of it” as is mentioned by Bittman. If the film Food, Inc. is anything to go by then there might be pressure from corporations to adopt their commercial practices over the ones that farmers have used in the past.
Clearly, agriculture is not like assembling IKEA furniture nor should it be treated like a car manufacturing plant, in other words, there is no “fool-proof” clearly delineated formula to growing plants in a way that has no impact on the Earth and natural systems. Now it’s time to bridge science and research with policy-making to effect change for a more conscience and sustainable way to grow our food.