Peak Phosphorus=Peak Industrial Agriculture?

Peak oil gets all the hype. I'm not saying it's not important; it's an issue that certainly deserves more serious attention than we are giving it. But there are other crises also looming in the dangerously not-so-distant future. Crises like peak phosphorus.

This probably doesn't come as any big surprise. Phosphorus is just another natural resource on the long list of resources that we are exploiting beyond their limits. But you may not realize how vital phosphorus is to our current agricultural system, and therefore how vital it is to the production of our food. Modern agriculture is dependent upon phosphorus-based fertilizer inputs, which is sourced from phosphate rock. It is predicted that we will reach peak phosphorous in the next 30 years or so, after which point there will be a forced decline in phosphate mining, and therefore the end of cheap fertilizer, which is a foundational piece of industrial agriculture.

Phosphorus is an essential nutrient for plant growth and is a limiting factor in crop yields. In other words, without the addition of extra phosphorus via manufactured fertilizer the plant population is restricted to the natural supply of phosphorous within a given ecosystem and therefore cannot produce beyond natural limitations. Unfortunately, our food system is utterly dependent on being able to produce above and beyond the carrying capacity of natural ecosystems.

Although phosphorus is a non-renewable resource and there is no good substitute (yet) to replace the amount needed for large-scale agriculture, phosphorus is recyclable, which is somewhat hopeful. The trick will be capturing the phosphorous that remains, and creating more efficient systems so that phosphorus is not wasted. An effective solution that is already being employed in parts of Europe involves recapturing the phosphorus in human and animal waste. In Sweden and Germany phosphorus is recovered from municipal wastewater treatment plants and new technologies, like no-mix toilets are being developed for widespread use. The idea of recycling human waste and using sewage sludge for fertilizer doesn't sit well with everyone, but if done correctly it is completely safe and sanitary, and someday may be necessary.

Peak phosphorus and the decline of phosphate mining doesn't mean the end of agriculture, but it certainly means the end of agriculture as we know it. The end of reliance on phosphorus means the end of our reliance on industrial agriculture, and a forced shift to small-scale sustainable agriculture, for whom adequate phosphorus can also be sourced from compost and animal (and human) waste.

Photo Credit: R.J. Reynolds Tobacco Company Slide Set, R.J. Reynolds Tobacco Company, Bugwood.org