07 Jul 2011

Phosphate: A Critical Resource Misused and Now Running Low

Phosphate has been essential to feeding the world since the Green Revolution, but its excessive use as a fertilizer has led to widespread pollution and eutrophication. Now, many of the world’s remaining reserves are starting to be depleted.
By fred pearce

If you wanted to really mess with the world’s food production, a good place to start would be Bou Craa, located in the desert miles from anywhere in the Western Sahara. They don’t grow much here, but Bou Craa is a mine containing one of the world’s largest reserves of phosphate rock. Most of us, most days, will eat some food grown on fields fertilized by phosphate rock from this mine. And there is no substitute.

The Western Sahara is an occupied territory. In 1976, when Spanish colonialists left, its neighbor Morocco invaded, and has held it ever since. Most observers believe the vast phosphate deposits were the major reason that Morocco took an interest. Whatever the truth, the Polisario Front, a rebel movement the UN recognizes as the rightful representatives of the territory, would like it back.

Not many people would call phosphate a critical issue or one with serious environmental consequences. But even leaving aside the resource politics of the Sahara, it is an absolutely vital resource for feeding the world. It is also a resource that could start running low within a couple of decades — and one we grossly misuse, pouring it across the planet and recycling virtually none of it.

Bou Craa Conveyer Belt
Photo by Ed Darack
The Bou Craa mine in the Western Sahara sends phosphate down a 150-kilometer-long conveyor belt to the port of El Ayoun.
The world’s food supplies are alarmingly dependent on the phosphate fertilizer that is hewn from the desert of the Western Sahara. The vast open-cast mine at Bou Craa delivers several million tons of phosphate rock every year down a 150-kilometer-long conveyor belt, the world’s longest, to the Atlantic port of El Ayoun. From there, it is distributed around the world and made into fertilizer.

Morocco’s phosphate reserves are owned by the Office Cherifien des Phosphates, a Moroccan state agency. Given the almost unlimited executive powers of the Moroccan monarch, it might reasonably be said that most of the world's known reserves of phosphate are, in effect, owned by King Mohammed VI and his Alaouite dynasty, which has reigned in Morocco since the 17th century.

If the people of Western Sahara ever resume their war to get their country back — or if the Arab Spring spreads and Morocco goes the way of Libya — then we may be adding phosphate fertilizer to the list of finite resources, such as water and land, that are constraining world food supplies sooner than we think.

Phosphorus is one of the building blocks of all life. Every living cell requires it. Plants need phosphorus to grow as much as they need water. Many soils do not have enough to meet the voracious demands for phosphorus of the high-yielding crop varieties of the Green Revolution. But we can provide more by mining phosphate rock and turning it into fertilizer to spread on the land.

It takes one ton of phosphate to produce every 130 tons of grain, which is why the world mines about 170 million tons of phosphate rock every year to ship around the world and keep soils fertile.

Currently, only about 15 percent of that comes from mines in the Western Sahara and Morocco. But the only other large producers, the U. S. and China, mostly keep supplies for their own use. So Morocco is by far the biggest contributor to international trade, with more than half the total business. The people of India, the world’s largest importer, would be
Most of the world’s best phosphate reserves are gone, and those that remain are in just a handful of countries.
starving without Morocco’s phosphates. Brazil’s agricultural boom would never have happened otherwise.

Even more critically in the longer term, the U.S. Geological Survey says that of the 65 billion tons of the world’s known phosphate rock reserves — and the estimated 16 billion tons that might be economic to mine — almost 80 percent is in Western Sahara and Morocco. Add in China’s reserves, and the figure rises to almost 90 percent. The U.S., with 1.4 billion tons, is close to running out. You can see why agronomists are starting to get worried.

The world is not about to run out of phosphate. But demand is rising, most of the best reserves are gone, and those that remain are in just a handful of countries. Dana Cordell of Linkoping University in Sweden, who runs an academic group called the Global Phosphorus Research Initiative, says we could hit “peak phosphorus” production by around 2030.

As domestic production wanes, the U.S. is starting to join those countries — most of the world, in fact — that import phosphate from Morocco and the Western Sahara. American imports cross the Atlantic courtesy of Potash Corp, the Canada-based fertilizer company whose hostile takeover bid by the Australian mining giant BHP Billiton was blocked by the Canadian government last year. And phosphate mining in Florida, which is home to the world’s largest phosphate mine, is being challenged by environmentalists concerned about its impact on waterways and drinking water supplies.

Already, like other key commodities with once-dominant sources running low, the price of phosphate is starting to yo-yo alarmingly. Prices spiked at an 800-percent increase in 2008.

A century ago, much of the world’s internationally traded phosphate came from bones (a major English import at one time) and guano, excavated from Pacific islands where birds had been defecating phosphate for millions of years. But bones are not traded much any more, and most of the guano islands are now mined out. The island state of Nauru, for instance, is nothing more than a moonscape after decades of mining it to fertilize the grain fields of Australia.

The other key ingredient needed to fertilize modern high-productivity farm soils is nitrogen. We know how to “fix” nitrogen from the atmosphere. If the German chemist Fritz Haber hadn’t come up with his process in 1908, there wouldn’t have been a Green Revolution — and there wouldn’t be 7 billion people on the planet today. The nitrogen produced by this process is estimated to be directly responsible for feeding 3 billion of us.

But there are no new sources of phosphate. We continue to mine the rock — or we starve.

Phosphate strip mines are environment wreckers. They produce around 150 million tons of toxic spoil a year. Their massive draglines, huge slurry pipes, and mountainous spoil heaps dominate the landscape for tens of miles in key mining zones, whether in the North African desert or in
Can we find ways to recycle phosphate and keep it in the food chain where we need it?
Florida, a state that still provides three-quarters of American farmers’ phosphate needs.

The world’s largest mine is at Four Corners in an area known as Bone Valley in central Florida. The Four Corners mine covers 58,000 acres, an area five times the size of Manhattan. It is owned by Mosaic, a company recently spun off from agribusiness giant Cargill. Next door is the world’s second-largest mine, South Fort Meade. But South Fort Meade is living on borrowed time — its expansion plans are being opposed by local groups, and unless it can expand, the mine will have to close.

As the drag mines move south in Florida, anger has been growing about the environmental impacts. A million tons of mine waste, containing lows levels of radioactivity, are already piled up at dump sites around the state, and disputes are growing over promised mine cleanups. Rivers have dried up, and settling ponds have leaked.

Last year, the local chapter of the Sierra Club went to court to block Mosaic’s plans to extend the life of the South Fort Meade mine by expanding its footprint. The group is concerned about the fate of the Peace River, a vital source of Florida’s drinking water; it says the U.S. Army Corps of Engineers gave approval for the expansion without first conducting a full environmental audit. The case is unresolved to date.

As for the impending shortages of phosphate, will technological advances and market forces solve the problem? We certainly waste a lot of this most valuable resource. Globally, we allow some 37 million tons of phosphorus to spill into the environment each year. It mostly flows down sewers and agricultural drains into rivers and lakes, where it feeds the growth of toxic cyanobacteria and consumes oxygen, creating eutrophication and “dead zones.”


The Nitrogen Fix:
Breaking a Costly Addiction

The Nitrogen Fix: Breaking a Costly Addiction
Over the last century, the intensive use of chemical fertilizers has saturated the Earth’s soils and waters with nitrogen. Now scientists are warning that we must move quickly to revolutionize agricultural systems and greatly reduce the amount of nitrogen we put into the planet's ecosystems, Fred Pearce writes.
While nitrogen pollution tends to get top billing as a cause of eutrophication, cyanobacteria can often abstract nitrogen from the air. David Schindler, of the University of Alberta in Edmonton, and others have argued that limiting phosphorus pollution is the key to eliminating eutrophication.

So how can we stop phosphate pollution, recycle it, and keep it in the food chain where we need it? Composting crop residues would be a good way of recycling this valued nutrient back into the soil, cutting the need for new applications of fertilizer — so would capturing some of the 3 million tons of phosphorus that cycles through human bodies annually, after being consumed in our food. Cordell says we should give top priority to recycling our urine, which contains more than half of all the phosphorus that we excrete.

But another conventional technical fix for a resource in short supply — finding a substitute — is not available. Presently, there simply are no substitutes for phosphorus.


Fred Pearce is a freelance author and journalist based in the UK. He serves as environmental consultant for New Scientist magazine and is the author of numerous books, including When The Rivers Run Dry and With Speed and Violence. In previous articles for Yale Environment 360, Pearce has written about the environmental consequences of humankind’s addiction to chemical fertilizers and about how agribusiness threatens a critical African wildlife migration.

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Is this really an analysis, what a pity? morocco has enough for more centuries, try to document more.

Posted by docteur on 07 Jul 2011

Obviously this is a dead end. There are some (already old) ideas to use nature itself and efficient plants to suck up mineral from the ground (green manure) as intermediary crops. For instance buckwheat is a known rotation crop for wheat and has been part of the diet for centuries in Bretagne to make pancakes. It is also a plant that accumulate phosphorus more than its need.

It would be nice to have a quantitative survey on the potential of these methods both for nitrogen and phosphorus on different types of soil.

Besides it might just be a problem for agro industry rather than small scale farming which is more suitable for recycling wastes and for applying a labour intensive crop management closer to the system often said to be by far the most productive in term of biomass: the wild one.

Posted by kervennic on 08 Jul 2011

How did the line "The Western Sahara is an occupied territory" get in here? Less than 500,000
people live in the territory and historically it has always been as an important part of the "Maghrib" (Morocco) state as Fez or Marrakesh.

You're in for a huge disappointment if you think Morocco is going Libya's way.

Posted by Anonyblogger on 08 Jul 2011

Phosphorus is one of the inorganic macronutrients needed by all plants for the manufacture of phosphate containing nucleic acids, ATP and membrane lipids. Soils that have been heavily used for agricultural crops are often deficient in phosphorus, as are acid sandy and granitic soils. In landscaped urban soils, however, phosphorus is rarely deficient and the misapplication of this element can have serious repercussions on the plant, the soil environment, and adjoining watersheds.

If you have a nutrient deficiency that is not relieved by nitrogen addition, try a foliar application of likely nutrients and see if the symptoms are alleviated. This prevents excessive addition of mineral nutrients to the soil.

Posted by Principe R. on 08 Jul 2011

I think there has been numerous studies demonstrating that roses, like most terrestrial plants, maintain symbiotic relationships with beneficial fungi, right?

Plowing fields sun bakes the microorganisms, with ultraviolet radiation. It' the microorganisms that feed the plant nutrients and the difference between soil and dirt.

Soil is an living matter, full of life, while dirt is dead and a lifeless waste.

Growing plants on chemicals and steroids was an ambitious plan to speed up production, but fails to take into account the sustainability.

If modern agriculture wants to improve, it will need to address the issues of how plant are dependent upon their environment, no less than how humans are dependent upon their environment and plants.

The disruption of the ecosystem due to profiteering is the sole reason why chemical fertilizers are applied disregarding completely the equilibrium of homeostasis in the ecology of the environment.

Farming needs to be a holistic practice, that includes the whole picture. It will be difficult to imagine any multinational corporation like Monsanto who directly benefits from the practice of isolated manipulation, like genetically modified organisms that they would even consider any other point of view.

Nature has been around longer than humanity, and it will continue to exist long after humanity. So why shouldn't humanity adapt those practices used by nature?

The article just points out how humanity needs to manages their own activities upon nature. Without a conscience, how do you think that will happen? Will greed and corruption be motivation to do the right thing here?

How about some examples by any multinational corporation?

What about Monsanto, Chevron, Exxon, BP, Coke Cola, McDonalds, etc... Don't all of them all a huge negative impact on the environment that is passed on to society for nothing more than short term profits earned?

Posted by Amy Mollison on 08 Jul 2011

Fred Pearce states an indisputable fact. There is no substitute for phosphorus in agriculture, or indeed in life. Phosphate rock is a finite resource – at some point in time the earth’s supply may be exhausted. However, the data presented by Pearce supporting the notion that the world is running out of phosphate does not take into account recent findings by the International Fertilizer Development Center (IFDC) that show no indication that phosphate production will peak in the next 20-25 years or even within the next century. Estimates from IFDC’s October 2010 report, World Phosphate Reserves and Resources, found that global resources of phosphate rock suitable to produce phosphate rock concentrate, phosphoric acid, phosphate fertilizers and other phosphate-based products will be available for several hundred years.

The conversation about the world’s phosphate reserves and resources becomes distorted when it is only based on the wide range of data available on phosphate rock deposits prior to 1990. Since then, there is limited detailed information on world phosphate rock reserves and resources available in the conventional scientific literature. The IFDC study is an important first step in developing a more detailed and accurate estimate of world phosphate rock reserves and resources.

Pearce also touches upon the availability of phosphate in the United States, the second largest producer of phosphate fertilizer, and notes that the United States and China, the largest producer of phosphate, “mostly keep supplies for their own use.” That statement is simply untrue. The United States is in fact the largest exporter of phosphate fertilizer in the world and for years has typically exported more than half of its phosphate production.

Another important point raised by Pearce focuses on the environmental impacts associated with phosphate fertilizer use. While Pearce pointed out that excess phosphorus contributes to hypoxic zones, there was no mention of the great strides that have been made by the U.S. agriculture sector in enhancing fertilizer use efficiency which in turn minimizes nutrient losses to the environment. If someone were only to accept Pearce’s perspective on this particular topic, they would completely overlook the fact that between 1980 and 2010, U.S. farmers produced over 87 percent more corn using nearly 15 percent less phosphate fertilizer; overall, U.S. corn farmers grew 119 percent more corn per pound of phosphate fertilizer applied.* The increase in phosphate use efficiency for corn is an especially important example because the U.S. corn crop accounts for fully half of total phosphorus use in agriculture in the United States. It also demonstrates how enhanced technology and practices, which are strongly supported by the fertilizer industry, are making a difference by protecting the environment and the planet’s precious natural resources. More information regarding the fertilizer industry’s commitment to environmental stewardship is available at

Continuing the discussion of world phosphate reserves and resources is relevant and essential, but ensuring that the dialogue is based on accurate facts and research is just as vital.

*Computed from the U.S. Department of Agriculture’s National Agricultural Statistics Service fertilizer application rate data and corn acreage and production data.

Ford B. West
President, The Fertilizer Institute

Posted by Ford B. West on 08 Jul 2011

Isn't it true that all modern agricultural systems are dependent on continual inputs of phosphate fertilizers? ...and although there are many phosphorus compounds that are essential in the living cell. phosphorus itself is essential to all forms of life since it is part of DNA, right?

However, during the Jurassic period, a time when plants flourished nobody was mining phosphate, and yet plants were growing prolifically because nobody was using up more than their share, not even the dinosaurs, for hundreds of millions of years.

It's said that phosphate rock is formed in oceans in the form of calcium phosphate, called phosphorite. Phosphate rock takes 10-
15 million years to form from seabed to uplift and weather back into the environment upon land.

So it seems unless we want to wait around for 10-15 million years to harvest a phosphate crop, we had better manage our supplies to last until then?

Some good news is that deep-sea exploration of the world’s oceans has revealed that there are large deposits of phosphates on the continental shelf and on seamounts in the Atlantic and Pacific Oceans.

China has a reserve of 6.5 billion tonnes of phosphate, even more than Morocco.

So better management is needed of our environment resources, otherwise maintaining the population will become difficult without sufficient phosphate for food production.

Question, does it make a lot of sense to spend huge amounts of energy to mine phosphate so that it's used to grow plants for producing biofuel, that ends up depleting phosphate for food production? How do you recycle phosphate from biofuel?

Posted by Zhang Bao on 08 Jul 2011

If EBPR (enhanced biological phosphate removal) reactors are retrofitted into each waste treatment facility nationwide, an estimated 8.75 million metric tons of phosphorus could be recovered.

Implementation of EBPR reactors would therefore eliminate 94% of the US’s current dependency on raw phosphate rock. This would allow the current US reserve of phosphate rock to last over 2000 years!

Other methods to reclaim phosphate could come from the purification of river water containing runoff from commercial agriculture.

Posted by Amy Mollison on 08 Jul 2011

Due to high tech agriculture we have managed to swell the population of the planet to close to 7 billion people. It seems one of the consequences of this is that now billions of people are dependent on a single mine in Morocco for survival. Let's hope that this mine stays open and available; and that our complex food chain is not house of cards that one day collapses on us. I have a foreboding sense that our technical and fossil fuel laden solutions to world hunger will someday cause more pain and suffering than they alleviated.

Posted by John Dyer on 09 Jul 2011

As with so many sustainability issues, population control is central. Whether the time frame for running out is 20 years, 200 years, or 2000 years is irrelevant. We are leaving an environmentally and economically impoverished world for our descendants.

Posted by Chris Craig on 10 Jul 2011

I entirely agree with your analysis Fred Pearce. Yes. Chemical fertilisers wide use has made soils natural capacity to retain fertility. That is why there is growing awareness on Organic Farming.

Dr.A.Jagadeesh Nellore(AP),India

Posted by Dr.A.Jagadeesh on 11 Jul 2011

Sahara is a colonial place yet, an EEUU an France are the resposability. Onu has agree referendum, but France are negative.
Sunldley if Onu does not make referedum China or other country will welcome to live there in the westerm sahara....good idea ....
Posted by salvatore on 18 Jul 2011

This company seems to have made a good start at recovering from what we flush away. In recovering phosphorus and other nutrients, it reduces sewage plant maintenance costs and ends up producing a commercial fertilizer.

Posted by Krenit on 25 Jul 2011

What about reducing or eliminating the use of Phosphates in washing powder detergents? It is not necessary in order to clean clothes and adds substantially to the amount of Phosphate in wastewater - a big problem faced by the sewage treatment industry.

Posted by Maureen Webb on 08 Dec 2011

Thank you, Fred Pierce, for a great insight. Please let me add the following. I hope Mr. Ford B. West is right about a more extended time frame than the nearest estimates. But we are only arguing about a time frame. It looks as though we will have to farm without phosphate fertilizer. I would rather our leaders get started on a plan sooner rather than later. The fertility of land will control population. This looming situation was predicted by Justus von Liebig ( even before Fritz Haber) who invented fertilizer in the 19th century. He estimated that the world human population would return to around 2 billion from a peak of around 10 billion. As there is no useful phosphorus cycle, it seems unavoidable. We could be heading at best for mass starvation or at worst a terrible world war as well as mass starvation.
The so called energy crisis pales into insignicance because we will be able to adjust more gradually to lifestyle and economic change. But starvation of superpowers can only lead to conflict.

Hydroponic food production (the idea is to recycle nutrients) for wold wide food production of staple diet crops is not possible. we can't hermetically seal the worlds wheat belts in glass and plant, harvest, maintain temperature and pump nutrient through them. Only nature has such power. Vertical farming is even more outlandish as light is not available for most of the plants. Most plants need soil around their roots anyway and can't be grown hydroponically.
I think we need to forget about everything else and start talking about international planning of population control and adjustment to food scarcity for all our sakes.

I have read that food rationing in the UK produced a more healthy diet than that of today. Perhaps we will see and end to obesity and its related health issues! Surely this is a plan of hope. We have time. Lets talk to our members in government.

Posted by Matt Griffiths on 05 Jan 2012

it is needless to mention there are few natural sources of phosphorous, so there is need for adoption of organic farming to enable recycling.further there is urgent need for reduction of population should come down to zero growth level otherwise it would not be possible to meet the both ends.

Posted by asesh Lahiri on 12 Jan 2012

Although my point has little to do with phosphate per se, the third comment here, by Anonyblogger (brave name, that), cannot be allowed to stand.

He asks, ‘How did the line "The Western Sahara is an occupied territory" get in here?’. The answer is simple: because that is what it is. Morocco and Mauritania militarily invaded the Western Sahara in 1975, and Morocco has held it by force, against the clear wishes of it’s people, ever since.

I accompanied the Sahrawi guerrillas into battle against the Moroccan army several times in 1976, and again in 1981. They were superb soldiers (second only to the British SAS in my experience) who totally outclassed the numbingly incompetent Moroccans and, given time, they would probably have driven the Moroccans out of their territory (as they succeeded in doing with the Mauritanians) but for the cynical intervention of the French. (The latter have behaved in this issue with their customary reprehensible absence of any political morality whatsoever.)

The claim by Morocco that the Western Sahara is historically a part of its nation is absolute tripe - culturally and linguistically the two places have almost nothing in common. It was merely a land grab (with the phosphate mine as its prize) that the international community has, as usual, been too spineless to address. It is on a par with China’s annexation of Tibet, and Russia’s continuing hold over the peoples of the North Caucasus. All are morally and politically indefensible.

Posted by Nick Downie on 18 Feb 2012

The Sahara is and has been Moroccan territory, look at the older maps, Morocco spread as far south as Senegal and as far east as Barqua in Libya. Moritnia which is south of Morocco was part of Morocco until 1962. Also parts of today's Algeria are Moroccan but kept by France occupation which
lasted 100 years in Algeria, when France left those lands were kept under Algeria based on French map.

Posted by Fahd Rboub on 23 Apr 2012

Fahd, leaving aside your delusional claim that the Sultanate of Morocco once held sway over the entire Maghreb (unless, of course, you are muddling it up with the 12th century Almohad Caliphate), and also your ludicrous assertion that Moritnia [sic] was a part of Morocco until 1962 (I suggest you bone up on the history of French imperialism in North Africa), what on earth have “old maps” got to do with anything?

If, in the 21st century, we conducted international affairs on this basis, then the bankrupt Greeks could solve their problems by demanding shares of Iraqi and Iranian oil (courtesy of Alexander) Berlusconi and his mates could subsidise their bunga bunga parties by taxing the entirety of Europe and the Middle East (courtesy of the Romans) and the secular Turks could plant their flag in the holy places of Mecca (thanks to the Ottomans), grabbing a slice of Saudi wealth while they were at it. As for the nanny-state health-and-safety-conscious British, a quarter of the world’s map was not that long ago coloured an imperial pink which, by your reckoning, gives the UK a free hand to help itself to almost anything it fancies. Get real.

Just because Morocco has a kleptocratic monarchy with an eye for agricultural chemicals, this does not give it the right - with or without overt French and covert US connivance - to stomp all over and kill its weaker neighbours. Civilised peoples regard this as theft and murder.

Posted by Nick Downie on 25 Apr 2012

I know the author, Fred Pearce, has heard about the USGS revisions on world phosphate reserves, yet he chooses to ignore it and use outdated figures.

Either call the USGS and the Moroccan government liars, and manipulators intentionally leading civilization to its demise for monetary gain, or STFU about peak phosphorus.

In case your readers haven't heard (considering you choose not to inform them), in January
2011, the USGS issued an update to Morocco's reserves from 5 billion tons to 50 billion. Yes, a 10 fold increase.

That would mean without even considering recycling, our phosphate reserved wouldn't be depleted for over 300 years based on current consumption.

So who is full of it, the USGS or you Mr. Pearce?

Posted by Jack Welford on 20 Jul 2012

Forgot the link to the report:

Posted by Jack Welford on 20 Jul 2012



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