Worries about the Earth reaching its full carrying capacity for humans are nothing new, and they all come back to how much food we can grow. Our last case of the Malthusian heebie-jeebies, in the 1950s, was put to rest by the Green Revolution, wherein large international aid orgs boosted agricultural yields in the developing world two and three times using heftier breeds of seeds, more fertilizer and pesticides, industrial-scale processing and up-to-date machinery.
Well, since then the population has doubled, keeping up with increases in farm production. And the old Green Revolution strategy is facing three new constraints: Water, soil, and oil. (Synthetic fertilizer is currently made from fossil fuels; mechanized harvesting, planting, irrigation, and transport of crops all require energy, normally in the form of gasoline).
Genetic modification can lessen the need for pesticides and fertilizers, making it more palatable to some–not all–environmentalists. But controversy aside, GM is not the perfect techno-solution. A new study published this month showed that planting modified high-yield crops may cause diminishing returns. In side-to-side comparisons, high-yield varieties of broccoli, corn and wheat contained 5 to 40% fewer nutrients like minerals, vitamins, and proteins compared to varieties with more modest yields.
By 2050, when world population is expected to rise another 37% and peak at 9.2 billion, we’ll need a solution that balances all these constraints. It may have less to do with something concocted in a lab or welded in a factory than with more sustainable human behaviors: Conserving soil and water through biodynamic or permaculture techniques like terracing, crop rotation , and composting.