This post was inspired by the New Scientist piece, All the reasons why organic food doesn’t deserve such bad press (Christel Cederberg and Hayo van der Werf, March 16, 2020). Per the authors:
“Critics say organic farming is less efficient than conventional farming, and so uses more land, leading to greater deforestation, which causes higher carbon dioxide emissions and biodiversity loss. …[We acknowledge] intensive farming is often more efficient, since its yields are higher. But this doesn’t properly address all environmental aspects.
Organically managed land, however, has been shown to support biodiversity levels around 30 per cent higher than conventionally farmed fields.”
It might be argued that the land saved through conventional farming could be reserved for biodiversity and CO₂ absorption. But the relationship between agricultural intensification and reduced deforestation is unclear. In Brazil, for example, agricultural intensification has coincided with more deforestation.
Widespread use of pesticides is also a concern – between 1990 and 2015, global pesticide use has increased more than 70 per cent.”
Note how the authors conflate conventional farming with intensive agriculture. They are not the same thing. Conventional agriculture generally refers to any agricultural system in which chemical inputs are used. Intensive agriculture is a system of cultivation using large amounts of labour and capital relative to land area. As for organic agriculture, I’ll go with the definition offered by the Food and Agriculture Organization (FAO) of the United Nations: organic agriculture is a system that eliminates “the use of synthetic inputs, such as synthetic fertilizers and pesticides, veterinary drugs, genetically modified seeds and breeds, preservatives, additives and irradiation.”
While conventional and intensive agriculture both use synthetic fertilizers and pesticides, the mere use of chemical inputs does not in itself spell disaster for biodiversity. Precise application of synthetic fertilizers and pesticides can actually protect the environment more than application of their organic counterparts. The devil’s in the details. Consider the findings of a recent meta-analysis comparing the environmental impact of conventional versus organic agricultural systems:
“…ammonia emissions, nitrogen leaching and nitrous oxide emissions per product unit were higher from organic systems. Organic systems had lower energy requirements, but higher land use, eutrophication [a type of water pollution] potential and acidification potential per product unit.” Clark & Tilman, 2017
It’s true that organic farms typically support more biodiversity on the land being farmed than conventional farms, However, it is also true that cultivated land, whether organically or conventionally farmed, is worse for biodiversity than wild habitat, so the less land farmed, the better. Plus, conventional farmers can do lots of stuff to increase biodiversity on their land, e.g., :
Minimal tillage. Many of our best crop pollinators live underground for most of the year, sometimes at the base of the very plants they pollinate. To protect them, farmers should turn over soil only where they need to.
Targeted Insecticides. If farmers use insecticides, choose ingredients targeted to specific species and the least harmful formulations.
Precision Methods and Technology. Precision application of fertilizers and insecticides will eventually pay for the initial investment through increased yields, with the added bonus of protecting pollinators.
Conservation Cover. Permanent vegetative cover of native grasses, legumes, milkweed and other pollinator-friendly plants, which insures flowers are in bloom for as long as possible to provide nectar and pollen throughout the growing season.
Contour Buffer Strips. Strips of vegetation that run along a contour of a farmed field. This provides another place to ensure availability of valuable nectar and pollen plants for pollinators.
Filter Strips. Strips of vegetation next to water bodies, designed to filter sediment and nutrient runoff, protect water ecosystems and can include plants for pollinators.
As for the case of Brazil, where “agricultural intensification has coincided with more deforestation”, coincidence is not causation. Brazil’s deforestation has been driven by the expansion of pasture and feed crops for livestock, not intensive farming. In contrast, agricultural intensification in North America and Europe is directly linked to reforestation of previously farmed lands.
We have to go beyond categorical, either/or thinking to solve the problem of agriculture and the environment. It’s not about organic versus conventional. It’s about how to grow more food on less land while reducing environmental harm. So that soils remain healthy, more land reverts to wild habitat, and the rest of the biosphere isn’t poisoned by pesticides and fertilizer run-off (including manure). Integrated pest management and sustainable nitrogen management are examples of practices that reduce the “negative externalities” of farming - and they are perfectly compatible with conventional farming.
References:
All the reasons why organic food doesn’t deserve such bad press by Christel Cederberg and Hayo van der Werf/New Scientist March 16, 2020
Clark, M., & Tilman, D. (2017). "Comparative analysis of environmental impacts of agricultural production systems, agricultural input efficiency, and food choice" Environmental Research Letters, Vol. 12, No. 6.
Pretty, J., & Bharucha, Z. P. (2015). Integrated Pest Management for Sustainable Intensification of Agriculture in Asia and Africa. Insects, 6(1), 152–182. doi: 10.3390/insects6010152