terça-feira, 31 de maio de 2011

IFA position on the "phosphate peak theory"

Phosphorus is essential to virtually all living organisms. It is one of the three macronutrients that crops require in large amounts in order to grow. Phosphorous fertilizer products, either raw or processed, are a key input used by farmers around the world to improve agricultural production and ensure food security.
Phosphate rock is the primary source of phosphorus and the main raw material from which phosphorus fertilizer products are obtained. However, it is important to distinguish between phosphate rock and phosphorus:
Phosphate rock is a non-renewable resource. It has taken millions of years for the rock to be formed through geological cycles and events.
Phosphorus, on the other hand, is a renewable resource that can be re-used within economic and technical limits.
Concerns have been expressed about a possible “peak” in world phosphate rock production, which – hypothetically – could contribute to rising agricultural commodity prices and to food insecurity. In the past five years, based on several articles and studies, there has been speculation that world phosphate rock production might peak before mid-century due to the potential for increased phosphate fertilizer consumption in developing countries, resulting in eventual depletion of known reserves during the following decades.
Many experts do not agree with the “peak phosphate” theory. For example:
Phosphate rock reserves are a dynamic concept. The level of these reserves is regularly revised upward with deposit discoveries, technical evolution, and increases in commodity prices.
Modelling of future phosphate rock demand has not been adequate to establish how quickly reserves could be exhausted. Most models have not considered soil phosphorus dynamics, or the need to build soil phosphorus levels up to a critical level at which phosphorus use efficiency by plants would be optimal.
Predictions of “peak phosphorus” ignore the practicality and economic feasibility of phosphorus recycling and re-use.

> See the IFDC report for a discussion of these definitions.
In response to a lack of up-to-date information, the International Fertilizer Development Center (IFDC) carried out a study, World Phosphate Rock Reserves and Resources, that reassessed the phosphate rock reserves and resources of important phosphate-producing countries. This study, released in September 2010, concluded that global phosphate rock resources suitable for phosphate-based products, including phosphate fertilizers, were far more extensive than previously estimated. At current extraction rates, these resources would be available for several centuries. A few months later, in January 2011, partly based on information in the IFDC report, the United States Geological Survey (USGS) updated its widely used estimate of world phosphate rock reserves from 16 billion tonnes (the 2010 estimate) to 65 billion tonnes. This estimate is in line with the IFDC report’s world phosphate rock reserves estimate of 60 billion tonnes.
IFA supports the conclusions of the IFDC report that the world is not facing a peak phosphate event. The 2011 USGS estimate of world phosphate rock reserves also supports the conclusions of the IFDC report.

Should “peak phosphate” be considered an urgent issue?

According to the IFDC report, there is no indication that phosphate rock production will peak in the next decades or during this century. Based on a review of publicly available information from the scientific literature, the report presents an up-to-date assessment of long-term phosphate rock reserves and resources in key producing countries. Furthermore, it suggests that existing resources and yet-to-be-explored sources not taken into account in the report could add substantial additional tonnage to this assessment. The report calls for a collaborative research effort to pursue a more detailed and accurate estimate of world phosphate rock reserves and resources. The IFDC will be conducting a second phase of their report covering these gaps.

The fertilizer industry is committed to the sustainable use of all phosphorus resources. It encourages research and best nutrient management practices for better recycling of all safe phosphorus sources of organic and inorganic origin.

> Fertilizer Best Management Practices (FBMPs)
Based on these recent assessments by IFDC and the USGS of world phosphate rock reserves (and of current phosphate consumption), IFA does not believe that peak phosphorus is a pressing issue, or that phosphate rock depletion is imminent. Nevertheless, it believes that efforts to minimize phosphorus losses to the environment and optimize phosphorus use should be encouraged.
It is important to note that research so far has focused on a possible peak in phosphorus supply. However, a potential peak in phosphorus demand should also be investigated. Since phosphorus accumulates in agricultural soils, phosphorus requirements do not increase linearly with agricultural production. There is a need to increase phosphorus levels to a critical level that optimizes phosphorus availability to plants while maintaining soil fertility. The steady improvement of soil phosphorus levels in Asian and Latin American countries, possibly leading to a peak in world phosphate fertilizer demand by 2050, is a scenario that has so far been overlooked. IFA has established an industry-wide task force on Phosphate fertilizer demand looking at different consumption scenarios.

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