So, Is Organic Food Actually More Sustainable?
At Columbia, a culture of heightened environmental consciousness has led to the proliferation of sustainable food options: Meatless Mondays at the dining halls, weekly farmers markets, and active student groups. I myself am heavily involved in this culture of “sustainable” eating, keeping to a plant-based diet and seeking out organic, non-GMO, rainforest-friendly products at the grocery store. Growing up in a liberal, eco-conscious community in Northern California, I was told time and time again that organic food was the most environmentally friendly option. Yet even with this upbringing, I never learned about our food production systems.
Naomi Zimmerman is an Environmental Science and Economics student at Barnard. She is interested in all things related to sustainability and climate justice, including climate refugees and sustainable food systems. She runs a blog about how college students can live more sustainably, and is involved with the Sustainable Initiatives Consulting Board and the Energy and Environment working group of the Roosevelt Institute.
Recently, in my sustainable development class, we learned about conventional versus organic food systems, and the fact that organic food was not always the most sustainable option blew my mind. Despite my efforts to adopt a sustainable diet, I came to realize that I, and many of my peers, do not know much about the sources of our food and their implications for the planet. Rather, we had grown to accept broad generalizations about what a sustainable diet looks like — plant based, organic, and non-GMO.
Using renewable energy and reducing waste are featured prominently in the media, dominating the popular environmental discourse and leaving food systems sorely overlooked. But in my sustainable development class, I was shocked to learn that food systems are the largest contributor to environmental degradation. The production, transportation, and consumption of food on a planet containing over 7 billion people is incredibly carbon intensive. Agriculture contributes to a third of the global greenhouse gas (GHG) emissions due to land conversion. Additionally, global food output is expected to double by 2050.
With such high stakes, we need to look beyond the labels and choose systems of food production that are the most sustainable. For me, this journey starts with the questions: What is organic food? How is it produced? And is it really more sustainable than conventional agriculture?
Organic food is grown without synthetic inputs such as chemical pesticides or synthetic fertilizers. Organic farms instead use natural approaches and fertilizers, such as crop rotation and manure, to control pests, diseases and weeds. This minimizes the exposure of farm workers, consumers, and the environment more broadly to harmful pesticides.
When used in conventional agriculture, pesticides and fertilizers can create a host of environmental issues. Certain pesticides can poison non-target organisms such as birds, fish, and plants, and harm organisms of special ecological importance, such as bees and algae. Pesticides also often contaminate soil as well as surface and groundwater. A United States Geological Service study found that over 90 percent of water and fish samples from streams contained one or more pesticides. Fertilizers that run off into streams and other waterways cause eutrophication—a process in which excess nitrogen and phosphorous buildups lead to algal blooms and excess production of carbon dioxide. The process results in acidic waterways with dead zones, or areas that are so low in oxygen that they kill marine life.
Since it does not include the use of synthetic pesticides or fertilizers, organic agriculture is very sustainable in many aspects. Organic farms tend to have more fertile soil, use less energy, and sequester more carbon. Research has shown that organic farms use 45 percent less energy, release 40 percent less carbon emissions, and foster 30 percent more biodiversity compared to conventional farming.
This being said, organic farm practices are not necessarily always the most sustainable option. To control pests and weeds without using pesticides, organic farmers often lay down sheets of black plastic over the soil surrounding their crops. This warms the soil and accelerates the rate of plant growth while preventing erosion. Black plastic also allows the usage of drip irrigation, which lets water drip slowly into the roots of plants, saving water. However, the glaring issue with lining huge swaths of land with single-use plastic is that it creates an immense amount of waste. Biodegradable plastic, a more sustainable alternative, isn’t allowed under United States Department of Agriculture (USDA) organic rules because it contains petroleum.
The overall sustainability of organic agriculture is further complicated when land-use is taken into consideration. Since it does not use synthetic fertilizers or pesticides, organic agriculture has a 25 percent lower crop yield compared to conventional farming. Many organic farms also rely on tilling — stirring up soil by running blades through it — to kill weeds in place of conventional pesticides and herbicides. The resulting loss of topsoil, the most agriculturally productive component of soil, contributes to these lowered yields. In a world that must use finite arable land to feed an ever-growing population, optimizing resources is crucial. A greater demand for agricultural land could incentivize even more deforestation and land clearing, threatening biodiversity and reducing carbon stocks.
On the flip side, just because produce isn’t labeled “organic,” it doesn’t mean it’s not sustainable. Many small or community-based farms grow crops in a way that is just as, if not more, sustainable than “organic” food production. Obtaining the USDA’s organic certification is very expensive and requires going through a heavily bureaucratic process. This can act as a barrier to many small farms, which may not use synthetic pesticides or fertilizers, and may even implement other sustainable practices that go far beyond requirements set by the USDA. For instance, the USDA organic requirements instruct farms to wrap food in plastic, which many smaller farms choose not to do. Small farms also tend to plant more diverse crops compared to conventional industrial agriculture. Additionally, locally sourced food creates less carbon emissions due to reduced transportation distances. Organic doesn’t necessarily equate to being local, and oftentimes the latter choice is more sustainable.
So, it turns out there isn’t a definitive answer to my question. When the costs and benefits are weighed for both organic and conventional agriculture, experts have argued that the most sustainable diet should ideally be sourced from both organic and conventional agriculture, depending on the type of food. Fruit and vegetables, for which nutritional value is the main priority, should be grown organically. Grains and other staple crops, in which caloric density is the main priority, should be grown conventionally. Ultimately, sustainable food production is a tradeoff between optimizing yield and minimizing environmental degradation.
Beyond the way food is produced, a sustainable diet is also about the types of foods we choose to eat. A diet that has the lowest environmental impact is plant-based and made up of local, seasonal foods. Cutting out foods with high GHG emissions, like meat and dairy, is imperative to cutting down your carbon footprint. Buying local isn’t as impactful as changing what types of foods you are buying, as transportation of food only accounts for 6 percent of the climate footprint of food systems — though, if you can, buying produce that is in season from a local farmers market is optimal.
The consumption, or lack thereof, of food is also a major driver of climate change that is often overlooked. Food that is produced but not consumed contributes to 3.3 billion tons of greenhouse gas emissions, making wasted food the third highest emitter of greenhouse gases following the US and China. Whether food was produced using conventional or organic methods is just one component in the complex webs that characterize our food system. Looking beyond labels means engaging more seriously with the environmental costs of our everyday choices, and encourages us to make more holistic and meaningful lifestyle changes.
by Naomi Zimmerman |February 5, 2020
Source: State of the Planet
