Feeding more than 8 billion people - how serious is the phosphorus depletion problem?

Phosphorus supplies are essential to farming and they affect agricultural output. Its increasing price and scarcity could change global agricultural patterns and the role of fertilizers.

We obtain nitrogen from the air, but we must mine phosphorus and potassium. The world has enough potassium to last several centuries. But phosphorus is a different story. Can we recycle efficiently it?

http://www.futurepundit.com/archives/006255.html

http://www.foreignpolicy.com/articles/2010/04/20/peak_phosphorus

“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.”

“Phosphorus is used extensively for a variety of key functions in all living things, including the construction of DNA and cell membranes. As it is relatively rare in the Earth’s crust, a lack of phosphorus is often the limiting factor in the growth of plants and algae. In humans, it plays an essential role in bone formation. Without a steady supply of this resource, global agricultural production will face a bottleneck, and humankind’s growing population will suffer a serious nutrition shortage. The world’s reliance on phosphorus is an unappreciated aspect of the Green Revolution, a series of agricultural innovations that made it possible to feed the approximately 4.2 billion-person increase in the global population since 1950.”

Any thoughts?