Shifting towards organic agriculture is a crucial step in creating a more sustainable food system, but scientists recently highlighted a limitation within the practice that keeps it from being a long-term climate solution.
What is organic farming?
In short, organic agriculture means less chemicals and more of the natural stuff.
According to organic farming regulations at all levels -- state, national, and international -- farmers practicing organic agriculture need to use manure like cow poop instead of synthetic fertilizer, or sow chemical-free seeds and transplants instead of those coated with pesticides.
In contrast, conventional, or industrial, agriculture contributes nearly 75 percent of yearly global eutrophication in freshwater and oceans. Industrial agriculture also contributes 23 percent of global greenhouse gasses emitted each year.
We have crossed seven out of eight boundaries beyond which the Earth is no longer “a safe operating space for humanity,” and the agricultural sector plays a critical role in pushing us beyond those boundaries by reducing available water, altering global land-use, contributing to global greenhouse gas emissions, and eroding soils.
Despite the reality that industrial agricultural practices have reduced topsoil by over a foot on some farms in the Midwest U.S. and biodiversity, some environmental scientists believe there is an opportunity to mitigate the impacts of climate change through carbon sequestration by adopting new soil management strategies such as organic agriculture.
These researchers propose that we adopt organic agriculture because some farmers have shown at a small scale (organic agriculture currently accounts for less than 2% of all land-area used for farming) that it can improve soil health.
Scaling up organic operations should be quite promising; thus, Ulysse Guadaré and colleagues set out to find out just how much carbon we could sequester by transitioning to an all-organic agricultural sector.
Their findings, reported in Nature on June 29, however, suggest that organic agriculture may, in fact, be detrimental to putting, and keeping, carbon in the soil.
Limitations to organic agriculture
Organic farming is often accompanied by the introduction of other environmentally conscious practices like no till, crop rotation, and cover cropping. Thus, in their study, the research team investigated how soil carbon would change through two scenarios.
In the first scenario all farms would transition away from chemical fertilizers and limit how many livestock they raised, but changed nothing else. Here, they found that soil carbon declined; the reason being that there would be less inputs.
Without synthetic fertilizers and with fewer cows, crop yields declined, which meant less plant waste was going into the ground. And carbon in the soil would still decline even if only half all farms transitioned away from chemical fertilizers.
However, in the second scenario -- in which all farms transitioned away from chemical fertilizers and limited how many livestock they raised but introduced cover cropping -- the team found that just by adding cover crops, the amount of carbon in the soil would increase slightly from the industrial agriculture baseline.
Here, the reason being that cover crops keep soil moist and, thus, plant material, and cow poop, is recycled much more efficiently.
(Still, it should be noted that not all regions would see soil carbon increase: the Midwest U.S., Northwest South America, the Southern tip of Africa, and Southeast Asia all experienced declines.)
So, add in cover cropping to enhance residue recycling and the soil will sequester more carbon. However, for farmers making the transition, knowledge about the land you’re farming is critical.
Learning the Land -- Agroecology
The diverse climates and ecosystems across Earth necessitate equally differentiable and unique approaches to agriculture, which have largely been overtaken by industrial agriculture’s push to produce abundant food.
Thus, as Miguel Altieri says in an interview with the Real Organic Project, “[To] change industrial agriculture, [we] cannot use the same tools that created the industrial system.” That is, we cannot devise a new agricultural system simply based on counting carbon or other metrics, else we risk walling ourselves off from real and comprehensive solutions because they do not provide (immediately) satisfactory results.
Recently larger organizations such as the National Resource Defense Council and the Food and Land Use Coalition have spotlighted the need to develop principle-based changes to promote a fundamental transformation of our current food system. These are landmark moments signifying a shift in public opinion towards the core principles of agroecology, or the study of the ecology of agricultural systems.
The principles of agroecology include:
(1) Enhancing soil fertility/the quality of life for all species in an agricultural landscape,
(2) Breaking up monocultural fields to cultivate diversity across space (i.e., via polycultures) and time (i.e., via crop rotations),
(3) Avoiding losses (of nutrients, water, and biodiversity), and
(4) Promoting synergies (between species, but also between the culture, ecologies, and economies of agricultural communities and their environment).
“When you do agroecology -- or real organic -- you capture carbon as a consequence of your management,” Altieri continues, “Principles create the practices that enhance processes [inherent within each ecosystem.]”
Scaling up only one agroecological practice -- cover cropping with organic farming -- highlighted the idiosyncratic nature of an effective transition away from industrial agriculture. Specifically, a re-imagined food system must be one made up of many smaller farms, counter to our oligopolistic agricultural market. Today 60 percent of subsidized funding -- funding that supports farm operations -- go to the largest 10 percent of farms.
An agroecologically-informed food system, thus, must be committed to sustaining small farmers that benefit their communities as much as they benefit the surrounding natural ecology. If not, we risk further extracting from the soils that serve as the bedrock for the U.S.’s current industrial agricultural model long beaten and sucked dry; we risk further suffocating our air, water, and multispecies counterparts that have long been suffocated by toxic chemicals and foul emissions. We must commit to a complete transformation to improve our planet’s health and bring communities back within safe planetary boundaries.
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