6 Conclusion
As far as this can be said today, agriculture will always be dependent on phosphorus inputs. And at least in foreseeable future it is very likely that the prime source of phos-phorus for agriculture will be mineral phosphate fertilisers and therefore, ultimately, phosphate rock. Although phosphate rock is a finite natural resource and contrary to recently published articles predicting a "peak phosphorus" event within this century, the currently available information shows no clear indications that phosphate rock deposits are facing depletion any soon. At the same time, the inherent uncertainty of such pre-dictions needs to be emphasised.
Furthermore, a close inspection of price trends and their determinants reveals that none of the past price peaks were triggered by physical phosphate rock scarcity but in-stead by a combination of demand increasing factors, long capacity expansion lead times and, possibly, by an oligopolistic market structure.
But even though mineral phosphate deposits might not run out in the near future, there can be no doubt about the finiteness of this resource. Given that phosphorus as a nutrient is not substitutable in agriculture the only alternative to the use of phosphate rock-based mineral fertilisers is using phosphate recyclates. In other words, unless the phosphorus cycle is closed, essentially through complete recycling, the supply of min-eral phosphate fertilisers is going to be finite. This is unlikely to be a problem within this 19
century, yet it remains a permanent threat in the long run. A fundamental question therefore is whether the market price mechanism will provide appropriate economic in-centives for phosphorus recycling early enough to prevent a peak phosphorus event and eventually a limited availability of this non-substitutable nutrient. A precautionary approach would surely include a strategy towards a more efficient use of phosphorus fertilisers and investment in recycling options.
Meanwhile, physical abundance of phosphate rock alone may not be enough to en-sure a safe and stable economic supply. On the one hand, this relates to the highly skewed distribution of global phosphate rock production and reserves which may lead to a further increasing dependency of phosphate importing regions and nations on only a handful of producing countries, such as China, Morocco and Russia. On the other hand, increasingly volatile phosphate rock and fertiliser prices can pose a risk, espe-cially to farmers in developing and emerging nations. In contrast to developed coun-tries, the soils in developing regions are often phosphorus-deficient and therefore quite responsive to fertiliser application. Consequently, a price shock that renders phosphate fertiliser unaffordable can be assumed to have more severe effects on agricultural yields in tropical countries than in the industrialised countries of the North with phos-phorus saturated soils.
In that sense, and although the "peak phosphorus" debate cannot be expected to provide a reliable depletion or peak estimate, it surely helped raise public, political and scientific awareness of a formerly barely noticed topic. As a result, inter- and transdis-ciplinary research networks and initiatives such as Global TraPs, the European Phos-phate Platform and GPRI have been founded and the European Commission aims at publishing a Green Paper on the topic (ENEP 2013; EPP 2013; GPRI 2011; Scholz et al. 2013a).
by Markus Heckenmüller, Daiju Narita, Gernot Klepper
As far as this can be said today, agriculture will always be dependent on phosphorus inputs. And at least in foreseeable future it is very likely that the prime source of phos-phorus for agriculture will be mineral phosphate fertilisers and therefore, ultimately, phosphate rock. Although phosphate rock is a finite natural resource and contrary to recently published articles predicting a "peak phosphorus" event within this century, the currently available information shows no clear indications that phosphate rock deposits are facing depletion any soon. At the same time, the inherent uncertainty of such pre-dictions needs to be emphasised.
Furthermore, a close inspection of price trends and their determinants reveals that none of the past price peaks were triggered by physical phosphate rock scarcity but in-stead by a combination of demand increasing factors, long capacity expansion lead times and, possibly, by an oligopolistic market structure.
But even though mineral phosphate deposits might not run out in the near future, there can be no doubt about the finiteness of this resource. Given that phosphorus as a nutrient is not substitutable in agriculture the only alternative to the use of phosphate rock-based mineral fertilisers is using phosphate recyclates. In other words, unless the phosphorus cycle is closed, essentially through complete recycling, the supply of min-eral phosphate fertilisers is going to be finite. This is unlikely to be a problem within this 19
century, yet it remains a permanent threat in the long run. A fundamental question therefore is whether the market price mechanism will provide appropriate economic in-centives for phosphorus recycling early enough to prevent a peak phosphorus event and eventually a limited availability of this non-substitutable nutrient. A precautionary approach would surely include a strategy towards a more efficient use of phosphorus fertilisers and investment in recycling options.
Meanwhile, physical abundance of phosphate rock alone may not be enough to en-sure a safe and stable economic supply. On the one hand, this relates to the highly skewed distribution of global phosphate rock production and reserves which may lead to a further increasing dependency of phosphate importing regions and nations on only a handful of producing countries, such as China, Morocco and Russia. On the other hand, increasingly volatile phosphate rock and fertiliser prices can pose a risk, espe-cially to farmers in developing and emerging nations. In contrast to developed coun-tries, the soils in developing regions are often phosphorus-deficient and therefore quite responsive to fertiliser application. Consequently, a price shock that renders phosphate fertiliser unaffordable can be assumed to have more severe effects on agricultural yields in tropical countries than in the industrialised countries of the North with phos-phorus saturated soils.
In that sense, and although the "peak phosphorus" debate cannot be expected to provide a reliable depletion or peak estimate, it surely helped raise public, political and scientific awareness of a formerly barely noticed topic. As a result, inter- and transdis-ciplinary research networks and initiatives such as Global TraPs, the European Phos-phate Platform and GPRI have been founded and the European Commission aims at publishing a Green Paper on the topic (ENEP 2013; EPP 2013; GPRI 2011; Scholz et al. 2013a).
by Markus Heckenmüller, Daiju Narita, Gernot Klepper
