Gwynne Dyer
Peak oil is so last year. Now we can worry about peak everything: peak food, peak soil, peak fertiliser, even peak bees.
Let’s start small. We depend on bees to pollinate plants that account for about one-third of the world’s food supply, but since 2006 bee colonies in the United States have been dying off at an unprecedented rate. More recently the same “colony collapse disorder” has appeared in China, Egypt and Japan.
Many suspect that the main cause is a widely used type of pesticides called neonicotinoids, but the evidence is not yet conclusive. The fact remains that one-third of the American bee population has disappeared in the past decade. If the losses spread and deepen, we may face serious food shortages.
Then there’s peak fertiliser, or more precisely peak phosphate rock. Phosphorus is a critical ingredient of fertiliser, and it is the eightfold increase in the use of fertilisers that has enabled us to triple food production worldwide from about the same area of land in the past sixty years.
At the moment we are mining about 200 million tonnes of phosphate rock a year, and the global reserve that could be mined at a reasonable cost with current technology is estimated at about 16 billion tonnes. At the current level of production it won’t run out entirely for eighty years, but the increasing demand for fertilisers to feed the growing population means that phosphate production is rising fast.
As with peak oil, the really important date is not when there are no economically viable phosphate rock reserves left, but when production starts to fall. Peak phosphate is currently no more than forty years away — or much less, if fertiliser use continues to grow. After that, it’s back to organic fertilisers, which mainly means the urine and faeces of ten or twelve billion human beings and their domesticated animals. Good luck with that.
Peak soil is a trickier notion, but it derives from the more concrete concept that we are “mining” the soil: degrading and exhausting it by growing single-crop “monocultures”, using too much fertiliser and irrigating too enthusiastically, all in the name of higher crop yields.
“We know far more about the amount of oil there is globally and how long those stocks will last than we know about how much soil there is,” said John Crawford, Director of the Sustainable Systems Program in Rothamsted Research in England. “Under business as usual, the current soils that are in agricultural production will yield about 30 percent less…by around 2050.”
The United Nations’ Food and Agriculture Organisation estimates that 25 percent of the world’s soils that are currently under cultivation are severely degraded, and another 8 percent moderately degraded. (Even “moderately degraded” soil has lost half its capacity to store water.) And the only way to access new, undamaged soil is to deforest the rest of the planet.
All of which brings us to the issue of peak food. And here the concept of “peak” undergoes a subtle modification, because it no longer means “maximum production, after which yields start to fall.” It just means “the point at which the growth in production stops accelerating”: it’s the peak rate of growth, not actual peak production. But even that is quite ominous, if you think about it.
During the latter part of the 20th century, food production grew at around 3.5 percent per year, comfortably ahead of population growth, but the dramatic rise in crop yields was due to new inputs of fertilisers and pesticides, much more irrigation, and new “green revolution” crop varieties. Now those one-time improvements have largely run their course, and global food production is rising at only 1.5 percent a year.
Population growth has slowed too, so we’re still more or less keeping up with demand, but there are signs that food production in many areas is running up against what researchers at the University of Nebraska – Lincoln in a report last year called “a biophysical yield ceiling for the crop in question.” Production of the food in question stops rising, then may even fall – and extra investment often doesn’t help.
The “peak” in this context is an early warning that there will eventually be a complete cessation of growth, possibly followed by an absolute decline. Peak maize happened in 1985, peak rice and wild fish in 1988, peak dairy in 1989, peak eggs in 1993, and peak meat in 1996. (The numbers come from a recent report by scientists at Yale, Michigan State University and the Helmholtz Centre in Germany in the journal “Ecology and Society”)
More recent peaks were vegetables in 2000, milk and wheat in 2004, poultry in 2006, and soya bean in 2009. Indeed, sixteen of the 21 foods examined in the “Ecology and Society” report have already peaked, and production levels have actually flattened out for key regions amounting to 33 percent of global rice and 27 percent of global wheat production.
So we are already in trouble, and it will get worse even before climate change gets bad. There are still some quick fixes available, notably by cutting down on waste: more than a third of the food that is grown for human consumption never gets eaten. But unless we come up with some new “magic bullets”, things will be getting fairly grim on the food front by the 2030s.
Gwynne Dyer is an independent journalist based in London
