In Search of Sustainable Phosphorous

Blog post by Lisa Dirks -- I attended the Sustainable Phosphorus Summit on February 3-5, where Phosphorus experts from around the globe convened to discuss the future of this essential element to life.  When the average person hears the word they may think of high school chemistry and the periodic table, but the speakers and organizers made it a fun topic, sporting pins that said, “P is for people!” and “Save the P[ee]!“. 

The final day included an interactive art display with interpretive dance, a decorative toilet, a snake, and P cycle puzzle.  But despite the light heartedness, the issue is a serious one about which most people are unaware.

Phosphorus, along with Nitrogen (N) and Potassium (K), is one of the key elements of chemical fertilizer and thus our food system.  However, critical issues are presently associated with P use.  One, example is eutrophication, as we discussed before.  Another is that P is a non-renewable resource.  Peak P is expected to occur around 2040.  However, by 2050 it is estimated there will be 9 billion people on earth.  Presently, we are at roughly 7 billion and there are starving people around the world.  Clearly, we have a growing global demand for food.  Geopolitical issues are also associated with this matter the primary global reserves of Phosphorus are in Morocco.  Summit conversations regarding the future of P began to sound very similar to peak oil and energy security.  However, in the case of oil we have renewable energy and other substitutes in the works.  Grimly, summit participants recognized there is no foreseen substitute for P. 

Given P’s limited reserves it’s expected that fertilizer production will become more expensive and energy intensive, as more work would be required to mine the remaining P of lower quality and accessibility.  P Summit scientists gathered into workshops to consider solutions and managing strategies.  Some suggested recycling phosphorus found in human urine and excreta (thus the “Save the P[ee]! “pin).  Others looked to transgenics.  For example Enviro-pig will excrete less P in its manure lessoning P run-off or genetically modifying crops to require less P and have more nutrient robust root systems. Other people suggested we just need to start using less phosphorus. 

The strong unifying outcry was for a synergizing solution.  Summit participants recognized that problems associated with phosphorus are complex and need to transcend an array of issues.   Ideally, this solution would take on green house gas emissions, eutrophication, improve soil quality and erosion, eliminate or reduce water pollution, be affordable and accessible to people around the globe, capable of large scale use and production, and be as good or better than conventional fertilizer  for crops. 

It was an exciting realization that GreenHarvest could play a significant role as a synergistic product to thwart a phosphorus crisis.  GH is both a soil amendment and fertilizer.  It does not have issues regarding scaling up, it contains no phosphorus, has 70% less N than conventional chemical fertilizer, recovers nitrogen 1.4 times more efficiently and uses nitrogen 2.7 times more productively than chemical fertilizers,  it increases soil quality, reduces erosion and run-off, rejuvenates poor quality soils, preliminary research has placed production related GHG at about 1/3 of that of conventional chemical fertilizer, it is cheaper than conventional fertilizer, and has statistically equivalent yields.

Sustainable Phosphorus Summit Information: http://sols.asu.edu/frontiers/2011/index.php

Sustainable P Initiative: http://sustainablep.asu.edu/home

Sustainable Phosphorus Futures website: http://phosphorusfutures.net/