Forget oil and water wars ...

Think, phosphorus wars?

From Kansas to China's Sichuan province, farmers treat their fields with phosphorus-rich fertilizer to increase the yield of their crops. What happens next, however, receives relatively little attention. Large amounts of this resource are lost from farm fields, through soil erosion and runoff, and down swirling toilets, through our urine and feces. Although seemingly mundane, this process cannot continue indefinitely. Our dwindling supply of phosphorus, a primary component underlying the growth of global agricultural production, threatens to disrupt food security across the planet during the coming century. This is the gravest natural resource shortage you've never heard of.
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The geographic concentration of phosphate mines also threatens to usher in an era of intense resource competition. Nearly 90 percent of the world's estimated phosphorus reserves are found in five countries: Morocco, China, South Africa, Jordan, and the United States. In comparison, the 12 countries that make up the OPEC cartel control only 75 percent of the world's oil reserves.
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The United States has only 12 phosphorus mines. The supplies from the most productive mine, in Florida, are declining rapidly -- it will be commercially depleted within 20 years. The United States exported phosphorus for decades but now imports about 10 percent of its supply, all from Morocco, with which it signed a free trade agreement in 2004.
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Already, signs are emerging that our current practices cannot continue for long. Between 2003 and 2008, phosphate fertilizer prices rose approximately 350 percent. In 2008, rising food prices sparked riots in more than 40 countries. Although the spike in fertilizer prices was only partially responsible for the higher food prices, the riots illustrate the social upheaval caused by disruptions to the world's food supply. The 2008 food riots were only stopped by government promises of food subsidies -- a viable strategy only as long as governments can afford the ever-increasing costs of food support.

Ponder.

And yes; this is required.