What's missing in the yield gap debate between organic and conventional agriculture
Updated: Jan 25, 2022
Let’s imagine the following scenario: there is a city on the margins of a river, upwards of which there is a forest. This forest makes all sort of contributions to the life of the city; it serves as a tourist attraction, as a park for the city’s population, as a refuge for a certain kind of migratory bird, as a space for research by agroforestry professionals of a nearby university, as a containing agent in case the river threatens to flood the city and, finally, as a source of wood for the local lumber industry. For the lumber industry, the goal is very much a clear one: chopping down more trees requires hiring more labor and machinery, but leads overall to higher earnings. Higher earnings and more labor requirements would lead, in turn, to more taxes for the city and reduced unemployment rates. So why not chop down the whole thing, and make a feast with the remains of the forest?
For the argument's sake, let's imagine that this city (in reality the city of Bageshwar, India) is the city of our scenario: forest, river and city are all interrelated and coexist.
In spite of this simple calculation, the proposal to allow the whole forest to be chopped down for wood would be unpopular at the very least, no matter how many jobs and how much of an economic boom could that bring: it is widely accepted that the forest provides many other services to the city, and focusing on exploiting just one would be unwise, unsustainable, and could end up with the city being wiped by a flood. A good forestal policy would be to establish a reforestation rate, with a maximum number of trees that can be cut each year, so that the city can have a lumber industry and a forest instead of ending up without a forest and, as a consequence of that in the long run, without a lumber industry either.
That is one of the arguments underlying a 2019 paper that provides an insightful discussion into the yield gap debate between proponents of organic and conventional agriculture. What this argument seeks to propose is that we, as a society, should reframe the role that yield has in agriculture: the main concern of agriculture is to provide food security, and an unsustainable system of producing food cannot be called better simply because its yields are higher. To draw from our example, the yields of a lumber industry without forestal regulations would indeed be higher, but at what cost? What is the cost of attaining higher yields in conventional agriculture, in terms of soil erosion, eutrophication, biodiversity loss, and increased greenhouse gas emissions? Organic agriculture, the authors observe, does a far better job in balancing the evident yield requirements of agriculture with the environmental requirements that will enable the next generations to feed themselves as well.
Adding to that, the authors also discuss the large variability that exists not only among studies presenting the extent of the yield gap (resulting in gap estimates that range between 9% and 25%) but also among individual cases of application of organic techniques and, especially, among regions. Organic Fertilizer could actually help increase agricultural yields in developing regions, providing, at the same time, higher resistance to changing climatic conditions and ensuring food security: a case registered in the paper notes, for example, how yields of organic corn and soybean were 37% and 52% larger than conventionally-planted corn and soybeans, under drought conditions. Our own studies in greenhouses in Qatar show that, under those specific conditions, organic methods can obtain 35%-40% higher yields with a reduction of 20% in input costs of fertilizer, water, and labor.