Lack of phosphorus threat to global food production

 The ability to provide enough food to feed people is dependent on the availability of phosphorus.  We are rapidly exhausting our reserves, show LiU researchers.

Shortages of phosphorus are a threat to feeding the world’s population. It is time to tackle this growing problem, warn LiU researchers.
“Phosphorus is as vital for food production as water. Yet, we are rapidly exhausting our phosphate rock reserves. At current rates, they will be depleted in the next 50 to 100 years. And just within a few decades, the shortage will cause severe problems – unless something is done”, Dana Cordell says.
Dana is a doctoral student both at Tema Water and Environmental Studies at Linköping University, and the Institute for Sustainable Futures at the University of Technology in Sydney, Australia. In the autumn of 2009 she will submit her thesis on the global phosphorus issue.

Phosphorus is necessary for all life. We get our phosphorus from the food we eat, which in turn comes from the phosphate fertilisers we apply to crops.
Around 90% of all phosphate rock extracted globally is for food production. There is no substitute for phosphorus in regard to food production.
This makes it necessary to properly manage and recycle phosphorus. One measure that can be taken is composting food waste. Currently about 30% of food is thrown into the garbage. Another measure that can be taken is developing systems for separating human excreta from other more polluted industrial wastewater to facilitate the reuse of urine and faeces.

“What we eat is also important. The more meat we eat, the more phosphorus we use. We have seen a growing consumption of meat both in the western world and in many countries in Asia”, says Tina Schmid Neset, who is a postdoctoral researcher at Tema Water and Environmental Studies and at the Centre for Climate Science and Policy Research, conducting studies on sustainable food production and related resource use.
“It is also possible to use phosphate fertiliser more efficiently. By doing this we minimise the problems that eutrophication leads to in lakes and rivers.”

 The demand for phosphorus has increased sharply, and this has led to rapidly increasing prices. In the period leading up to March 2008, the price of the raw material – phosphate rock – increased more than 700% within 14 months. Prices have since declined, but they are still three times higher than two years ago.
The remaining reserves are geographically concentrated in just a few areas in the world.
“Almost two-thirds of the remaining high-grade phosphate rock reserves are found in China, Morocco and Western Sahara”, says Dana.

At the same time she tells us that almost all exports from China have ceased last year, when China imposed an export duty of 135% on its phosphate rock to safeguard domestic fertiliser resources. Furthermore, many Scandinavian companies have chosen to boycott Morocco who occupies Western Sahara and controls its phosphate rock reserves. This occupation has been condemned by the UN.
Other countries with relatively large reserves of phosphate rock are South Africa, the USA and Jordan.

A change in how we manage phosphorus resources is also necessary if we are going to succeed in eliminating hunger in the world. More food needs to be produced, while at the same time dealing with the increasing demand for phosphorus that is quickly consuming limited resources.
“It has been calculated that ‘peak phosphorus’, that is when global production of phosphate rock will reach a maximum, will occur in 2030. And that is not very far off considering there are currently no alternatives on the market that could replace the demand for phosphate rock at any significant scale. Not much is being said about these issues on the international stage. Phosphorus scarcity needs to be added to the political agenda”, says Dana.

Now Dana Cordell and Tina Schmid Neset in co-operation with Swedish and Australian research colleagues are trying to focus the spotlight on the phosphorus issue. They are calling their initiative the Global Phosphorus Research Initiative (GPRI). Together they are gathering data, writing articles and arranging seminars.
“We have received a good response. GPRI is quoted in many contexts. Interest seems to be growing”, says Tina hopefully.

Text: Lennart Falklöf
Photo: Peter Modin

Footnote: Read more about the Global Phosphorus Research Initiative at
www.phosphorusfutures.net.