Food is fast becoming a critical issue in a world of changing climate. In order to address this challenge, consumer choices in food will have to become much more sustainable than they are at present. In this instance, sustainable covers a variety of scopes, including converting to primarily plant-based diets, eliminating pesticides, using natural fertilizers, reducing greenhouse gas emissions (GHGs), preserving biodiversity, limiting food miles, and maintaining quality and quantity of water. This post will examine the best possible choices a consumer can make in terms of most limiting their environmental impact. In particular, this post will assess the intrinsic pros and cons of two ostensibly-sustainable forms of agriculture: organic and local.
Before examining organic and local agriculture, the distinction between plant-based diets and conventional diets (which incorporate meat) must be taken into consideration. Lamb and beef are particularly unsustainable, with red meat producing 1.5 times as many GHGs as white meat. To compare the vegetarian versus the non-vegetarian diet, a study performed in California showed that the conventional diet requires 2.5 times more energy, 2.9 times more water, 1.4 times more pesticides, and thirteen times more fertilizer than a vegetarian diet. This indicates that the first requirement of sustainable food choices relies upon a diet that greatly limits meat consumption, while focusing primarily on plant-based foods.
With the requirement for a primarily plant-based diet established, the next requisite is that the produce purchased be free of pesticides. Organic foods are ideal for this—either organic-certified or foods from farmers who grow crops according to organic practices. Organic foods prevent pesticide runoff that pollutes water supplies and soil.
Organic agriculture also utilizes natural fertilizers that produce greater yields and have a much smaller impact on the environment than their synthetic counterparts. Synthetic fertilizers do add necessary compounds for plant health, but do not add the microbes necessary for long-term soil health—destroying the soil’s vitality and ability to produce food. Synthetic fertilizers (and synthetic pesticides) must also be manufactured industrially, adding to greenhouse gas emissions. However, in terms of greatest crop yields, according to Lingfei et al. (2018), “25% N substituted with organic fertilizer (OM25) produced the highest yield [in tea plants].” This means that a combination of seventy-five percent organic fertilizer and a synthetic, twenty-five percent nitrogen produces greater yields in tea plants than both purely organic and purely synthetic fertilizers. Similar results were found in the study of tomato plants, which showed that a combination of synthetic and organic fertilizers produced the greatest yields in tomatoes. This implies that a combination of synthetic and organic fertilizers may be the most ideal in terms of greatest crop yields, even though it is less sustainable than purely organic fertilizer.
On the whole, organic production limits the amount of greenhouse gases injected into the atmosphere. This is primarily due to the lack of synthetic fertilizers and pesticides used in organic operations.
The next topic is biodiversity. Unfortunately, neither local nor organic agriculture ensures the preservation of biodiversity. However, there are ways to limit future loss: by purchasing from growers who actively cultivate a wide variety of fruits and vegetables in a polycultural manner. The Desert Oasis Teaching Gardens (DOT Gardens) at the Albuquerque Academy, New Mexico, are a prime example of this; the DOT Gardens grow not just varying rows of different crops, but different crops within the rows themselves in order to preserve biodiversity and the health of the soil.
Planting a Spring Garden by the Desert Oasis Teaching Gardens. The wide variety of crops within the rows preserves biodiversity and the health of the soil.
As for food miles, both local and organic production show very little difference in transportation emissions. This is demonstrated by Coley et al. (2008), whose study shows that a mere round-trip drive of 6.7 kilometers (approximately 4.2 miles) to buy organic food produces more carbon emissions than cold-storing, packing, and transporting food to a food hub and to a customer’s home—i.e. the conventional method of produce supply. Weber and Matthews (2008) also emphasize this point, explaining that, because eighty-three percent of emissions are devoted to the production phase of food, simply not eating red meat once per week has a greater GHG footprint reduction than buying entirely local food.
The final factor depends on water quality and quantity. There is no evidence that local or organic food uses less water than their counterpart, but there is evidence that organic farms have less impact on water sources due to a lack of pesticide use. According to a study performed by Bohnet et al. 2018, if all farmers in Australia alone were to transition from conventional to organic farming, then the quality of water would improve by fifty-six percent. Organic farming is a key method for conserving the quality of drinking water.
The Planetary Health Plate by the EAT-Lancet Commission. The above plate is considered both healthy and sustainable. It consists primarily of plant-foods, with small sources of animal products to maintain human health.
With a transition to mostly-plant-based diets, with animal products mainly consisting of chicken, eggs, and dairy, organic agriculture is largely more sustainable than purely local production. However, there is growing corporatism in the organics industry that is leading to “cut corners,” including massive numbers of organic chickens only being allowed small porches for outdoor access, as well as insufficient pasture space for organic dairy cows. Because of this, the best option is to become familiar with growers and their practices, as solely purchasing from farms with an organic label discredits those farmers who do practice organic farming (without cutting corners), but simply cannot afford the USDA Organic seal (which is expensive and difficult to maintain). In this case, it is important to recognize the origins of the food production and to discover inputs used (type of fertilizer, pesticides, et cetera). There is also the fact that buying local food improves the economy of an area, particularly if impoverished, because it allows money to recirculate in the community longer. All-in-all, buying organic food saves the planet, while buying local food saves the farmers. Ergo, buying organic food from local farmers provides the best of both the economical and the environmental worlds.
-Posted by Heather