By Alyson Center, Board Member
As Earth Day approaches on April 22nd, let’s think about where food comes from, and how we as members and patrons of Just Food Co-op, support systems that promote environmental health. Food ultimately comes from the soil. Healthy soil contains multiple components including mineral particles like sand, gravel, silt and clay, and dead organic matter that stores nutrients and gives soil its dark color. Healthy soil also contains an abundance of organisms including bacteria, worms, fungi and insects that recycle and release nutrients that plants can use. The upper Midwest has some of the best soil for farming because of rich glacial silt deposits and amenable climate. However, conventional agriculture both causes and suffers soil and environmental degradation. Specifically, the industrialization of agriculture and the shift to intensive monoculture farming for increased efficiency and productivity has slowly degraded the soil needed to produce food and negatively impacts the surrounding environment. The causes of soil degradation are complex and often location specific, but frequently include soil loss from water and wind erosion, and soil degradation from excessive fertilization, reliance of synthetic pesticides, and routine plowing. Over the past 50 years, it is estimated that over 1,900 million hectares or 7.3 million square miles of agricultural land has been degraded to some extent and about 15% of that and has been severely degraded1. While the causes of soil and environmental degradation are exceedingly complex and have numerous interdependent causes, let’s examine one major factor: the reliance on monocultures.
The shift from diversified farming methods to growing a single crop or type of animal in a large area (monoculture) was the solution to feeding the world that began in the 1960s with the Green Revolution. This shift in farming practices marked the beginning of the industrialization of food systems. While the use of monocultures and the intensification of agriculture have greatly increased crop productivity, the environmental consequences are becoming increasingly apparent. For example, a study by the Minnesota Pollution Control Agency (2016) found that the water quality of the Mississippi River rapidly declines south of St. Cloud because of increased run-off and nutrient pollution from farms2. The decline in water quality is directly related to how farmers fertilize their fields. In addition to relying on fertilizers, farmers that grow crops in monocultures have to rely on pesticides because of the inherent vulnerability of pest outbreaks when a single species in planted over a large area. The overuse and reliance on pesticides has lead to the evolution of resistance in many pest species populations, which in turn requires farmers to either switch chemicals and/or apply more concentrated does. Monocultures require seasonal applications of fertilizer to increase crop yields. If farmers do not know the amount of nutrients their soil can hold (called the cation exchange capacity), they will undoubtedly over-fertilize which results in nutrient leaching into ground water, and/or surface run-off into local waterways. Over-fertilization not only affects our local aquatic ecosystems but also contributes to the Dead Zone in the Gulf of Mexico. Excessive nutrient pollution from farms (mainly nitrogen and phosphorous) destabilizes aquatic systems through a process called eutrophication, which results in extremely low oxygen levels in water. Once oxygen levels in an area of water drop below a critical point, the aquatic system can no longer support life and is called a ‘dead zone’. The largest dead zone in the world occurs at the mouth of the Mississippi River and spans an area of over 8,500 sq. miles, or roughly the size of New Jersey1.
While large conventional farmers rely on monocultures to increase efficiency but contribute to environmental degradation, sustainable farmers use principles found in nature to build healthy soil and increase crop productivity. Many of the local farmers around Northfield that sell products through Just Food are part of Sustainable Farmers Association (SFA), and explicitly produce food in ways that promote environmental health. For example, a sustainable farmer may plant crops in polycultures (multiple species interplanted) or use stripe farming, where different crops are plants in alternating rows. These sorts of planting methods help protect soil and reduce the reliance on pesticides (synthetic or organic approved) by increasing environmental complexity and reducing the chance of outbreaks by pests. Additionally, unlike most conventional farm systems where soil is left bare post-harvest, sustainable farmers frequently plant cover crops after the main crop is harvested. Bare soil is highly vulnerable to water and wind erosion and cover crops reduces this risk by physically covering the soil and from plant roots that hold onto and stabilize the upper soil layers. Additionally, cover crops can reduce the need for fertilizers because specific plants like legumes (nitrogen fixers) can be planted as part of the cover crop. These plants can be tilled into the soil and increase fertility by feeding soil organisms and adding to the soil organic material. While the practices of sustainable farming are more costly and time consuming, they are essential to building and maintaining a healthy environment.
Just like the industrialization of crop production, the increased productivity of animal operations has come from monocultures. Intensive monocultures in animal systems are commonly known as concentrated animal feeding operations (CAFOs), where thousands of animals are housed in confined settings and largely fed corn and soy. Because of the intensive nature of CAFOs they produce large amounts of waste. It is estimated that CAFOs produce more than 500 million tons of manure annually, which is more than three times the amount of sewage produced by humans in the US per year3. Unl
ike human waste, manure is not treated but collected and contained in sewage lagoons and often applied directly to agriculture fields as fertilizer. Additionally, healthy animals in CAFOs are continuously fed antibiotics in their feed to both promote growth and reduce the risk of disease. There have been numerous studies linking CAFOs to the evolution of antibiotic resistant bacteria, like Staphylococcus aureus, the bacteria responsible for staph infections. Research by Dr. Nadimpalli and colleagues (2016) found that 44% of CAFO hog workers that participated in their study had S. aureus bacteria in their noses after they left work and half of those bacteria were resistant to multiple antibiotics. It should be noted that not all of the antibiotics used in animal systems are also used to treat humans, but some of them are. Additionally, many CAFO farms are contract farmers for large corporations and have clauses in their agreements that limit access and research on these farms5.
Unlike large CAFOs, sustainable organic animal farmers may use pasture systems and rotate animals across a landscape to mimic grazing patterns of herd animals. These types of open practices increase soil fertility since roaming animals disperse their waste across the landscape where it can be decomposed and naturally integrated into soil just like in natural ecosystems. Alternatively, animal waste from chicken coops or barns can be collected and composted and then applied as an organic fertilizer that helps to build soil by increasing organic matter (one of the components of soil). Additionally, the sustainable and/or organic farmer does not feed antibiotics to their animals (and cannot to be certified organic), which reduces the potential public health risk inherent in the over-reliance of antibiotics in conventional systems. When we shop at cooperatives like Just Food, we are supporting the alternative to big conventional agricultural systems because co-ops, unlike other ‘natural’ food stores, are major supporters of local and small farmers that produce food using the principles of nature and not the conventional industrial model.
1Cunningham, W. P., & Cunningham, M. A. (2013). Principles of environmental science: Inquiry and applications. Boston: McGraw-Hill.
2Our Upper Mississippi River. (2017). Retrieved from: https://www.pca.state.mn.us/sites/default/files/wq-iw8-08ab.pdf
3Rogers, S., & Haines, J. (2005). Detecting and mitigating the environmental impact of fecal pathogens originating from confined animal feeding operations: review.
4Nadimpalli, M., Stewart, J. R., Pierce, E., Pisanic, N., Love, D. C., Hall, D., … & Heaney, C. D. (2016). Livestock-Associated, Antibiotic-Resistant Staphylococcus aureus Nasal Carriage and Recent Skin and Soft Tissue Infection among Industrial Hog Operation Workers. PloS one, 11(11), e0165713.
5Moyer, M. W. (2016). How Drug-Resistance Bacteria Travel from the Farm to Your Table. Scientific American.