Large retail chains are discovering that reducing greenhouse gases is easier said than done, reports NPR. Specifically Walmart, which unveiled Project Gigaton, a plan to reduce its emissions of greenhouse gases by a billion tons of carbon between now and 2030 — almost as much carbon that is released from the country’s entire fleet of passenger cars and trucks in a year — found an unlikely culprit to be one of its biggest greenhouse gas emitter. When calculating the climate price tag of its products, Walmart found that baked goods such as bread were very big emitters and the footprint does not come from factories or fleets of trucks, but rather, the farms, whose use of nitrogen as a fertilizer is having a big environmental impact not only on bodies of water, but through greenhouse gas emissions.
Nitrogen is so widely used because it is a very important nutrient for plants but the production of nitrogen fertilizer is energy-intensive and requires the burning a lot of fossil fuels. Additionally, the bacteria that feed on nitrogen release nitrous oxide, a powerful greenhouse gas. The article states, “According to one study, carried out by the consulting group Deloitte, greenhouse emissions from fertilizer are the biggest single piece of the global warming price tag for almost half of the top-selling items on the shelves at Walmart.”
Reducing the emissions that result from farming proves to be difficult undertaking because the only way to do so is to communicate directly with farmers. No one else along the supply chain has any control over the use of nitrogen. A fertilizer dealer, the very beginning of this supply chain, came up with a potential solution that became a company called SUSTAIN, which helps farmers use fertilizers more wisely in an effort to mitigate greenhouse gas emissions. SUSTAIN was purchased by Land O’Lakes in 2015 and the company has pledged to Walmart that it will enroll 20 million acres of farmland in SUSTAIN by 2025.
Because it may cut into profits, most farmers are unwilling to voluntarily use less nitrogen, so SUSTAIN attempts to help them use nitrogen differently. For one, farmers apply the fertilizer several times during the season instead of all at once, buy stabilizers that mix with the nitrogen to prevent it from washing away so quickly and they log data on nitrogen use into a program that monitors weather and predicts how much nitrogen will remain in the soil. Unfortunately, while this does make farmers’ nitrogen use more efficient, it hasn’t been shown to actually reduce the amount of nitrogen used.
Critics say that while careful management of fertilizer is a good thing, it’s simply not enough to reduce green house gases and SUSTAIN does not encourage other dramatic solutions such as growing different crops. One proposal, for example, would be to incentivize farmers to add “small grains” such as oat and rye to their mix of crops. Crops like oat pair well with “cover crops” such as clover, which adds nitrogen to the soil organically, replacing the need for synthetic nitrogen. While farmers understand the benefits, says NPR, the market for such alternative crops is unknown and they are unlikely to take the risk.
All this demonstrates how when procedures become institutionalized, they are next to impossible to roll back. Demand forces these farmers to produce a steady supply, and for many, this required the use of fertilizer. How do we encourage agriculture that is sustainable to those that are part of a cycle that is difficult to break and doing so can be damaging economically? Walmart’s Project Gigaton is an admirable undertaking that hopefully succeeds, but so far it has served to illuminate how much more complex the issues of greenhouse gases and climate change really are as well as the challenges involved with mitigating these factors.