What if we could simultaneously (i) lower our environmental impact while cooling the planet; (ii) improve social equity in the food industry; and (iii) still feed the estimated 10 billion people living on planet Earth in 2050? I argue that addressing each of these challenges requires a transformation of the agricultural sector from using the green revolution approach to methods based on the principles of agroecology. Below, I will briefly compare ways that green revolution agriculture and agroecology impact the environment, social equity, and food production. I realise that in doing this in such a short piece I will inevitably make a caricature of both approaches, and I apologise for this.
In short, green revolution agriculture prioritises yield maximisation of a single monoculture through intensive land and chemical use; while agroecology [pdf] prioritises the ability of farmers to feed themselves and their community by producing a wide variety of crops making use of natural cycles rather than chemical inputs. While there are many ways in which agroecological systems contribute to the environment (e.g. creating habitats for biodiversity, carbon sequestration, and preventing soil erosion), as well as ways in which monoculture farms harm the environment (e.g. destroying natural habitats, relying on fossil fuels, and putting unsustainable pressures on land), I will focus on table 1 taken from Altieri (1999):
The table compares a sample of traditional low-input (in this context referring to old peasant agriculture), modern high-input (referring to green revolution agriculture), and agroecological systems in Bolivia for a single crop: potatoes. It shows that yield ha-1 is highest in the high-input farms, though it should be noted that the agroecological system produced multiple crops, and therefore might have a higher total yield. More importantly, table 1 expresses that agroecological systems used no fertiliser and produced substantially more (30.5 potatoes) output per unit of energy, compared to green revolution agriculture. The latter used 200 kg ha-1 of fertiliser, and produced only 4.8 potatoes per unit of energy. Thus, while green revolution farming actively contributes to harming the planet through the consequences of fertilisers and energy consumption, agroecology rejects these practices while actively contributing to the planet by, among other things, restoring habitats for biodiversity and sequestering carbon.
Besides creating a production process that has a positive impact on the environment, agroecology also tackles inequalities that are persistent in the current food system. The food industry is shaped as an hourglass: there are many peasants and farmers at one end; with monopolies in each of the three sectors – input supply (seeds, machinery, chemicals), processing and retail, in the middle; and many consumers at the other end. In consequence, power is concentrated at the food corporations, which results in situations where, for example, grain seeds for are only sold to farmers if they also purchase the associated pesticides and fertilisers (input); or, prices are set and farmers either accept or lose any chance at making a revenue (processing); or, Tesco and Walmart setting private standards that need to be complied with by suppliers shifting the cost of government regulations on these suppliers (retail). Agroecology, by promoting the production of food for local consumption, tries to bypass the food corporations in the middle of the hourglass and directly delivers food to consumers. This allows peasants to earn higher income. In addition, by replacing chemical and technical inputs with natural processes, farmers reduce their dependency on the inputs provided by corporations. Agroecology is therefore a more socially equitable form of agriculture.
Recently, scientists, politicians and industry representatives are sounding the alarm bells, warning that global food production needs to double by 2050 [pdf] to feed everyone on the planet. So, given the rejection of the green revolution technology and intensification, will agroecology be able to provide the necessary amount of food? First, Altieri & Nicholls (2012) [pdf] argue that the world today already produces the amount of food necessary to feed 10 billion people, but that currently the majority of industrially produced crops feed biofuels and animals. Second, Altieri & Nicholls note that small scale peasant agriculture already accounts for at least 50% of agricultural output for domestic human consumption. This, despite the fact that the majority of peasant production suffers from productivity declines associated with degraded land due to pesticide use, failed harvests due to high vulnerability to shocks, and more, all associated with the consequences of green revolution agriculture. In addition, their data suggest that agroecological interventions in conventional agriculture in 57 different countries in the Global South resulted in an average crop yield increase of 79%. Third, agroecological farming is less vulnerable and more resilient to shocks. Machin Sosa et al. (2010) [pdf] studied crop loss and crop recovery in Cuba following hurricane Ike in 2008 and found that agroecological farms had 50% crop loss, compared to 90-100% in monoculture farms. They also concluded that the recovery rate of vegetation in the former was substantially higher than in the latter. In a world that will increasingly experience variable and extreme weather events, agroecological farms will be better prepared and produce more food.
Bottom Line: Transforming agriculture from green revolution principles to agroecological principles can result in a positive impact on the environment and a more equitable food system, while not coming at the cost of reduced food production to feed a growing human population.
* Please help my Environmental Economics students by commenting on unclear analysis, alternative perspectives, better data sources, or maybe just saying something nice :).