Phosphorus: Essential to Life—Are We Running Out?

applying phosphorus fertilizer

Fertilizing a corn field in Iowa. Photograph credit: U.S. Section of Agriculture

Phosphorus, the 11th most common element on earth, is central to all living things. Information technology is essential for the creation of DNA, cell membranes, and for bone and teeth formation in humans. It is vital for food product since it is i of three nutrients (nitrogen, potassium and phosphorus) used in commercial fertilizer. Phosphorus cannot exist manufactured or destroyed, and in that location is no substitute or synthetic version of it available. There has been an ongoing contend about whether or not nosotros are running out of phosphorus. Are we approaching summit phosphorus? In other words, are nosotros using it upwards faster than we can economically extract it?

In fact, there is plenty of phosphorus left on Earth. Animals and humans excrete almost 100 percent of the phosphorus they consume in food. In the past, every bit part of a natural bike, the phosphorus in manure and waste was returned to the soil to assist in ingather production. Today phosphorus is an essential component of commercial fertilizer. Because industrial agronomics moves food around the globe for processing and consumption, disrupting the natural cycle that returned phosphorus to the soil via the decomposition of plants, in many areas fertilizer must now be continually applied to enrich the soil's nutrients.

Almost of the phosphorus used in fertilizer comes from phosphate rock, a finite resource formed over millions of years in the world's crust. Ninety percent of the world's mined phosphate rock is used in agriculture and food production, generally as fertilizer, less equally animal feed and food additives. When experts contend peak phosphorus, what they are usually debating is how long the phosphate rock reserves, i.east. the resource that can economically be extracted, volition hold out.

Pedro Sanchez, director of the Agriculture and Food Security Center at the Earth Constitute, does not believe there is a phosphorus shortage. "In my long fifty-year career, " he said,  "once every decade, people say we are going to run out of phosphorus. Each time this is disproven. All the nearly reliable estimates show that we have enough phosphate rock resource to last between 300 and 400 more years."

In  2010, the International Fertilizer Development Eye adamant that phosphate stone reserves would concluding for several centuries. In 2011, the U.S. Geological Survey revised its estimates of phosphate rock reserves from the previous 17.63 billion tons to 71.65 billion tons in accordance with IFDC'south estimates. And, according to Sanchez, new inquiry shows that the amount of phosphorus coming to the surface by tectonic uplift is in the same range as the amounts of phosphate rock nosotros are extracting at present.

Global meat consumption from 1961 to 2009. Photo credit: FAO

Global meat consumption from 1961 to 2009. Photo credit: FAO

The duration of phosphate rock reserves will also exist impacted by the decreasing quality of the reserves, the growing global population, increased meat and dairy consumption (which crave more fertilized grain for feed), wastage along the food chain, new technologies, deposit discoveries and improvements in agricultural efficiency and the recycling of phosphorus. Moreover, climatic change will affect the need for phosphorus because agriculture will bear the brunt of changing weather patterns. Near experts concur, all the same, that the quality and accessibility of currently available phosphate rock reserves are declining, and the costs to mine, refine, store and transport them are rising.

Xc percent of the phosphate rock reserves are located in only five countries: Morocco, China, South Africa, Jordan and the The states. The U.Due south., which has 25 years of phosphate rock reserves left, imports a substantial amount of phosphate rock from Morocco, which controls up to 85 pct of the remaining phosphate stone reserves. Nevertheless, many of Kingdom of morocco'southward mines are located in Western Sahara, which Morocco has occupied against international constabulary. Despite the prevalence of phosphorus on world, only a pocket-size percentage of it can be mined because of physical, economic, energy or legal constraints.

In 2008, phosphate rock prices spiked 800 percent because of higher oil prices, increased demand for fertilizer (due to more than meat consumption) and biofuels, and a curt-term lack of availability of phosphate rock. This led to surging food prices, which striking developing countries particularly difficult.

With a world population that is projected to achieve 9 billion by 2050 and require 70 percent more than food than we produce today, and a growing global middle class that is consuming more than meat and dairy, phosphorus is crucial to global food security. All the same, in that location are no international organizations or regulations that manage global phosphorus resources. Since global need for phosphorus rises about 3 percent each twelvemonth (and may increase as the global center form grows and consumes more meat), our power to feed humanity will depend upon how we manage our phosphorus resources.

Unfortunately, almost phosphorus is wasted. Only 20 percent of the phosphorus in phosphate rock reaches the food consumed globally. Thirty to 40 percent is lost during mining and processing; 50 percent is wasted in the food chain betwixt farm and fork; and only one-half of all manure is recycled back into farmland around the earth.

Eutrophication in the Caspian Sea. Photo credit: Jeff Schmaltz, NASA

Eutrophication in the Caspian Sea. Photo credit: Jeff Schmaltz, NASA

Virtually of the wasted phosphorus enters our rivers, lakes and oceans from agronomical or manure runoff or from phosphates in detergent and soda dumped down drains, resulting in eutrophication. This is a serious class of water pollution wherein algae bloom, then die, consuming oxygen and creating a "dead zone" where nothing can live. Over 400 coastal dead zones at the mouths of rivers exist and are expanding at the rate of ten percent per decade. In the United States alone, economic damage from eutrophication is estimated to be $two.2 billion a twelvemonth.

As the quality of phosphate rock reserves declines, more energy is necessary to mine and process it. The processing of lower grade phosphate rock also produces more heavy metals such as cadmium and uranium, which are toxic to soil and humans; more than energy must be expended to remove them too.  Moreover, increasingly expensive fossil fuels are needed to transport approximately thirty million tons of phosphate stone and fertilizers around the world annually.

Sanchez says that while there is no reason to fright a phosphorus shortage, we exercise need to be more efficient about our use of phosphorus, particularly to minimize eutrophication. The keys to making our phosphorus resources more sustainable are to reduce demand and discover alternating sources. We need to:

  • Improve the efficiency of mining
  • Integrate livestock and crop production; in other words, apply the manure as fertilizer
  • Make fertilizer application more targeted
  • Prevent soil erosion and agricultural runoff past promoting no-till farming, terracing, contour tilling and the use of windbreaks
  • Eat a plant based nutrition
  • Reduce food waste from farm to fork
  • Recover phosphorus from human waste material

Cow dung to be used as fertilizer drying in Punjab. Photo credit: Gopal Aggarwal http://gopal1035.blogspot.com

Moo-cow dung to be used as fertilizer drying in Punjab. Photo credit: Gopal Aggarwal http://gopal1035.blogspot.com

Phosphorus can be reused. According to some studies, in that location are plenty nutrients in one person's urine to grow fifty to 100 percent of the food needed by another person. NuReSys is a Belgian company whose technology can recover 85 pct of the phosphorus present in wastewater, and turn it into struvite crystals that can be used every bit a irksome fertilizer.

New phosphorus-efficient crops are besides being developed. Scientists at the International Rice Inquiry Constitute discovered a gene that makes it possible for rice plants to grow bigger roots that absorb more than phosphorus. The overexpression of this cistron can increase the yield of rice plants when they are grown in phosphorus-poor soil. Rice plants with this cistron are not genetically modified, simply are being bred with modern techniques; they are expected to be bachelor to farmers in a few years.

A breed of genetically modified Yorkshire pigs, chosen the Enviropig, has been developed by the University of Guelph in Canada to digest phosphorus from plants more efficiently and excrete less of it. This results in lower costs to feed the pigs and less phosphorus pollution, since squealer manure is a major contributor to eutrophication. Last leap, notwithstanding, the Enviropigs were euthanized after the scientists lost their funding.

The Agriculture and Nutrient Security Center is working on food security in Africa and attempting to eliminate hunger at that place and throughout the tropics within the next two to three decades.

In the mountains of Tanzania along Lake Manyara, Sanchez' team has discovered deposits of "minjingu,"  high-quality phosphate rock that is cheaper and just every bit efficient equally triple super phosphate (a highly concentrated phosphate-based fertilizer) in terms of yields of corn per hectare.

Minjingu Mines & Fertilisers Ltd.. Photo credit: IFDC Photography

Minjingu Mines & Fertilisers Ltd.. Photo credit: IFDC Photography

Minjingu deposits are formed by the excreta and dead bodies of cormorants and other birds that roost and die in the mountains, forming biogenic rock phosphate or guano deposits. Guano, the feces and urine of seabirds (and bats), has a high phosphorus content, and in the past was often used as fertilizer.

Sanchez' researchers have likewise discovered a common bush chosen the Mexican Sunflower that is an efficient phosphorus collector. It grows by the side of the road, fertilized by the excreta dumped at that place by farmers. The farmers cutting it downwards and use information technology as light-green manure, an organic phosphorus fertilizer which helps grow high-quality crops similar vegetables.

Mexican Sunflower. Photo credit: John Tann

Mexican Sunflower. Photo credit: John Tann

The Agronomics and Food Security Center team likewise helps farmers contain erosion and runoff by encouraging them to keep some vegetative embrace, either alive or expressionless, on the soil twelvemonth-round. This is done through intercropping, leaving crop residue in the fields, contour planting on slopes or terracing.

"There is no data to support the idea of superlative phosphorus," said Sanchez. "Just fears. New deposits are continually existence discovered. We also accept more efficient extraction that is getting more phosphate rock out of country-based sediments. And there is an enormous 49-gigaton deposit of phosphorus in the continental shelf from Florida to Maritime Canada that scientists accept known about for years. Now there is some experimental extraction going on off the coast of Due north Carolina."

Pedro Sanchez, writer of Properties and Management of Soils in the Tropics published in 1976, which continues to be a bestseller, is currently working on Tropical Soils Science, an update of his previous piece of work. It will exist published by 2015.

Correction: This mail service was updated on March 22, 2019 to remove a statement that phosphorus is a renewable resource.