Phosphorus Crisis: A geo-strategic ticking time bomb

Phosphate mining

World is now facing the dread prospect of ‘peak phosphorus’ (the point at which the production capacity will peak before phosphate reserves gradually run out), just as we are warned of peak oil, peak coal, or peak uranium. Although, it is true that energy reserves (oil, coal, uranium) are depleting, they are not life-binding. Phosphorous, on the other hand, is crucial and elementary to all life on earth, without which human beings, animals and plants cannot survive. It is a vital nutrient element in the vigorous growth of plants, other than nitrogen and potassium. Nitrogen is readily available in the air that we breathe while there are surplus reserves of potassium to last for centuries. However, it is estimated that global supplies of phosphorus may start to run out by the end of this century. With the depleting resources, phosphorus prices will swing, thus raising additional supply concerns. Still, there are plenty of phosphate rocks available, but we must act now to conserve it, or it will be too late to revive our future agriculture.

Importance

Science fiction author and biochemist Isaac asimov once wrote, “Life can multiply until all the phosphorus is gone, and then there is an inexorable halt which nothing can prevent”. Human body requires a minimum consumption of 0.7 gms per day with their food to stay healthy. Phosphorus plays a key role in cell structuring and bone and teeth strength. Nerve cells, muscles and DNA molecules- all are dependent on the phosphate mineral. Also, in plants, it helps in enhancing leaf growth, yield, disease resistance, and overall health. In short, phosphorus is the building block of life.

Phosphorus Concentrated Resources

In fertilizers, phosphorus is the main ingredient in conjunction with nitrogen and potassium.  Phosphorus reserves are concentrated geographically. Morocco (main exporter, also known as, the Saudi Arabia of phosphorus), China, South Africa and U.S. are the four countries that control 80% of the world’s usable phosphate reserves and contribute approximately 2/3^rd of the annual phosphorus production. This amount can suffice for about 30 years of global demand. Trade-wise, increasing dependency on these countries will only make things worse, resulting in wild swings in tariff and market disruptions

The Phosphorus Chain

Phosphorous is naturally present as phosphate ion in phosphorus rocks. It is an irreplaceable ingredient of life. Weathering releases it into the soil from where it is absorbed by plants. Phosphorus, then, enters the food chain and makes its way through every living being. An average human body contains 650 gms of phosphorus.

Phosphorous is reused approximately 800 times by marine organisms (after reaching water bodies through weathering and runoff) before sedimentation. After millions of years of tectonic uplift, it gets back to dry land.

Agricultural Blunders

Harvesting breaks the natural cycle as it removes phosphorus from the soil. In ancient farming, human and animal compost was used as fertilizers which were rich in phosphorus, in turn, replenishing the soil with phosphorus. Modern day fertilizers limit our ability to return the favor.

On the other hand, farming also promotes land erosion because of continuous tilling and crop terracing. This further worsens the situation, leaving the soil deprived of its vital nutrient.

The Lethal Side of Phosphorus

Huge toxic blue-green algae feeding
on phosphorus

Eutrophication (an influx of nutrients, often a byproduct of agricultural run-off and sewage discharge) from eroded soil and human and animal compost end up in lakes and oceans, where it promotes uncontrolled cynobacterial (or blue-green algae) and algal growth. After they die, the fossils get collected at the bottom and consume all the oxygen present, thus choking aquatic life. This results in death of fisheries creating “dead zones”. U.S. waters have the largest dead zones off the Mississippi delta.

 Solutions

There are ways to restoring balance to the phosphorus cycle.

·         Integrate Farming: Recycling of human and animal byproducts as fertilizers can be a good start to refurbishing phosphorus back into the cycle.

·         Seeking new sources: Mining companies should start finding other reserves and research new ways to extract the mineral.

·         Sewage sludge: Sewage sludge is a rich source of phosphorus and can be processed for making fertilizers.

·         Reduce Erosion: No-tilling and plowing practices helps to lower soil erosion, leaving more phosphorus available for the next harvest.

·         Innovative ways: Urine is an excellent source of phosphorus. Sweden has taken initiatives to use this source by making special urine-diverting toilets. These function by sending urine to storage tanks for phosphorous recovery.

However, nature also has a back-up plan for the depleting vital nutrient. Biologist Mohamed Hijri brings to light a microscopic mushroom (arbuscular micorrhizal fungi), which is present in soil and helps in making phosphorus readily available to plant roots by forming a symbiotic relationship.

More to Explore-

Cordell, Dana. “Urine diversion and reuse in Australia: A homeless paradigm or sustainable solution for the future?” Masters Thesis Linköping University, Sweden, 2006.

Food and Agriculture Organization of the United Nations. Crop production levels and fertilizer use Food and Agriculture Organization of the United Nations, Rome: 1981.

Foster, John and Magdoff, Fred. “Liebig, Marx, and the depletion of soil fertility: relevance for today's agriculture - German chemist Justus von Liebig; Karl Marx” Monthly Review 1998.

Vaccari, David A. “Phosphorus Famine: The Threat to Our Food Supply”Scientific American (2009).

Phosphate Rock Statistics and Information. Available at http://minerals.usgs.gov/minerals/pubs/commodity/phosphate_rock/mcs-2013-phosp.pdf