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Output from the Young Scientist Workshop, Montpellier, France, August 31st, 2014.

October 14, 2014


In August 31, 2014, there were 42 young scientists from 20 countries gathered together at Montpellier, France at the Young Scientist Workshop in the midst of the phosphorus (P) week. These young scientists are mainly PhD students and postdoctoral fellows. This workshop was particularly focusing on developing their research network, reflecting on much broader questions related to P, generating novel ideas with regard to “phosphorus and society”, and holding a dialogue on these issues among participants from different countries.


In the beginning, the young scientists came together to network and establish a collaborative approach of multidisciplinary scientists to discuss the current and future of phosphorus at a global scale. Working collaboratively, they identified 6 key topics being: agronomy, P recycling, Geopolitics (Power, Responsibility, & Politics), P pricing, Multiple issues (intersection of environment, society, & economy), and P trilemma (producers, poor users, & rich users).

The output of the workshop was a conceptual model that describes the trilemma among P availability, usage, and need (Fig. 1). When a system is balanced, it has the adequate amount of need for P to apply in a reasonable rate to provide just enough available P for crops (Fig. 1a). When the system is imbalanced, it may appear as too much need for P, such as most of the African countries (Fig. 1b); or too much P usage and availability, such as most of the developed countries (Fig. 1c). The system can be in different scales from global to plant and soil interaction (Fig. 1d).

Six discussion points following the conceptual model had been developed for the further discussion in the 4th Sustainable P Summit:

  1. Which actors the responsibility for bringing about change?
  2. The inequity of P production, use and abuse
  3. The need for effective communication and education at all levels
  4. The honest engagement and understanding of stakeholders
  5. The need for global governance

A true collaborative approach of researchers, stakeholders, government with an emphasis on “No  One Size Fits All” solution is needed.


Anaerobic digesters and P recovery

September 16, 2014

This past summer I visited India to explore organic waste management operations that contributed to nutrient cycling. In today’s post I will discuss Jain Irrigation Systems Ltd (JISL). Founded on a philosophy that we should leave the world better than we found it, JISL pays close attention to environmental issues, farmer livelihoods, and the well being of both employees and customers. The company has a variety of operations, ranging from manufacturing solar panels and irrigation equipment, to propagating bananas and processing fruits and vegetables. While they appear to be on the leading edge of many different agricultural practices, it’s their industrial food processing and waste management that caught my attention.

As the food processing side of the company grew, management recognized they couldn’t rely on composting as their sole organic waste management approach. While they had significant amounts of land on which to dump the food waste, increasing volumes would create smell and insect problems, which could get them in trouble with local regulatory agencies.   After a number of experiments with various types of composting failed to meet their requirements, they partnered with a German company to design and build an anaerobic digester on site in 2012- the first of its kind in India.

During Mango season, processing into mango puree results in 300 tons of waste every day. The pit is mechanically sorted from the waste to be dried to be burned for energy, while the rest of the waste (~150 tons/day) is stockpiled for feeding the digester. Processing bananas, tomatoes, and onions provides additional feedstocks for the digester throughout the year, and a nearby sugar factory also sends its waste to JISL.

Not only does the digester create enough methane to run generators producing 1.7 Megawatts of power each hour, the exhaust from the generators is sent to a boiler where it makes steam, which is sent through a condenser where it creates 400 tons of refrigeration per hour for the food warehouse. Finally, the residuals from the digestion process are sent through a belt press to extract water (which is reused for irrigation, or in the digester) and the solids are sent to composting where they are mixed with other organic waste and sold back to the farmers supplying food to the factory.

Recovering and recycling P from the organic waste may have been an afterthought, but through this integrated systems approach, JISL has found an economical way to turn a waste product into energy and nutrient resources, while protecting the environment and their bottom line.

Jain AD compound

EPA Defines Waters of the United States

September 5, 2014

The US Environmental Protection Agency has released a draft definition of the term “waters of the United States” as covered by the Clean Water Act (CWA). The CWA regulates entities that discharge any pollutants, including phosphorus (P), into said waters.  However, which waters are or are not covered has been very vague since its passage 40 years ago.  It was often necessary to hire consultants to make case-by-case determinations for an individual pond, ditch, swale, or marsh.  Entities would be required to gain a NPDES (National Pollutant Discharge Elimination System) permit to discharge elevated levels of P  if the water body was determined to be jurisdictional, but were unregulated if the water body was determined not to be.  It would often be difficult to make an unbiased determination since the entity doing the discharging was the same sponsoring the study and would benefit from a non-jurisdictional finding.  The EPA seeks to clarify this confusion, save time and money in the determination process, and have uniform application by proposing the clearer definition.

The proposed new definition of “waters of the United States” generally narrows the scope of coverage.  It does not cover any new types of water and still does not cover groundwater.  It continues to cover large waters that are currently or historically useful for navigation or recreation.  The major areas of clarification came in defining coverage for tributaries, neighboring wetlands, and ephemeral washes.  These are now clearly jurisdictional if they contribute physical, chemical, or biological impact to a downstream regulated body.

This elucidation enables better P management to prevent nutrient loading and eutrophication for at least two scenarios.  First, several upland soil and water conservation practices continue to be excluded from jurisdiction. In addition, 56 other conservation practices established by the Natural Resource Conservation Service (NRCS) are now clearly excluded. The farmer can now implement nutrient runoff prevention and erosion prevention improvements without the need to gain expensive and time-consuming dredge/fill permits. Second, upstream wetlands that contribute to downstream water quality are now clearly included as jurisdictional.  Entities can no longer discharge unacceptable levels of P into a wetland, previously justified by the wetland not being jurisdictional itself and only indirectly affecting downstream waters.  The new clearer definition works to reduce P pollution in both scenarios.

In what ways do you think clarifying “waters of the US” will impact P management?  Read the proposed rule at  The EPA is accepting public comments until October 2014.

How can P runoff lead to a drinking water crisis? The case of Toledo, Ohio

August 20, 2014

Around 400,000 people in Toledo, Ohio are currently facing a drinking water crisis due to high levels of a dangerous toxin in their drinking water (1,2). The toxin is microcystin, released from a cyanobacterium Microcystis. A chain reaction following the blooming of the cyanobacteria exacerbates the water deterioration–the decomposition of the dead Microcystis consumes most of the oxygen in the water. This kills of almost all higher organisms since their lives depend on oxygen. The scientific term for this phenomenon is “eutrophication”.

A group of scientists in the Southern Extension and Research Activity – 17 (SERA-17) stated that the main cause of this algae bloom is P runoff from farmlands. Farming practices are particularly important in contributing to the P lost from the farm. Changing agricultural practices related to how and when to apply P fertilizer is crucial to solve the drinking water crisis in Toledo. In this article, I list some farming practices that could potentially be a source of P pollution and were discussed in SERA-17.

In the Maumee River watershed (as elsewhere), most of the P application is through chemical fertilizers. A common practice of applying chemical fertilizer is surface broadcast—a uniform application of P fertilizer on the soil surface. Surface application of P is prone to leaching by rainfall. When P fertilizer is applied in the fall combined with no-till practice, it becomes vulnerable to runoff through all winter. This could be prevented by occasional tillage to help with stratification and by less frequent but larger P applications.

Fertilizer application recommendations are set up in order to maintain agricultural productivity. However, these recommendations are often higher than what the crop actually needs. This has generally be done so as to keep farmers from coming back to the universities, extension offices, or fertilizer suppliers and complaining that their yield is lower due to low fertilization application recommendations.

Another potential source of P input to drinking water in Toledo is from decomposing vegetation during snowmelt or winter storm runoff either from no-till crop residue or the potentially large contribution from perennial, winter cereal, and cover crops. Besides the readily solubilized P released from the crop residues, organic P is another source that is converted by zebra mussels into inorganic P in Lake Erie.

The problem of toxic algae blooms is not just confined to the U.S., but has also been reported in several other parts of the world including China, Japan, Brazil, and Australia. Global climate change is also another potential threat for exacerbating such blooms, as increased temperatures and lake stratification also favor cyanobacteria. Identifying the hot spots of P runoff and reducing the amount of P in runoff are critical for improving water quality and preventing toxic algae blooms. Further improvements in farming practices can not only help us reduce P pollution but also help farmers save money by buying less P fertilizer without compromising marketable yield.



There is No P in Europe: EU Identifies Phosphate Rock as Critical Raw Material

July 2, 2014

A recently released European Commission report identified phosphate rock as one of its most critical raw materials (1).  The EU is concerned with securing access to materials used in a variety of products vital to sustaining and improving quality of life.  Phosphate rock is included as a critical non-food and non-energy material based on both its economic importance and supply risks (see figure below, courtesy European Critical Raw Materials Review).

Phosphate is important to the EU economically based on its usage in certain industries and the percentage of the gross domestic product associated with those industries.  The principal use of phosphate rock is for production of fertilizer, and so the reason it wields a large economic importance is its vital role in agriculture.  The report further identifies phosphate rock as the single most irreplaceable raw material, with only 2% of applications having a viable substitute.  Exasperated by low recycling rates, phosphate rock has a critical value in agricultural and overall economic production.


Figure from (1) showing P rock crossing EU “thresholds” for supply risk and economic importance, leading it to be classified as a “critical raw material”.

Risks on the supply side arise due to the heavy reliance on imports and the concentration of those imports from only three main sources.  The 28 member countries of the EU combined have less than 1% of the production capacity and less than 1% of the reserves of world phosphate rock (2), but must feed over 7% of the world population.  It therefore must rely heavily on imported phosphate to maintain its agriculture.

The primary sources of phosphate imports to the EU are from the United States, China, and Morocco.  The United States is the most stable trading partner of the three, but it is also the country that most egregiously over-mines its limited supply.  This of course leads to concerns over long-term production capacity and continued ability to meet demands of both itself and the EU.  In contrast, Morocco has the largest reserves in the world, but ranks the lowest in terms of stability as an economic partner due to continued disputes over the Western Sahara.  China ranks somewhere in the middle for both phosphate reserves and for trade stability.

Identifying phosphate rock as a critical material enables policies and initiatives to secure resources and spur efficient use and reuse.  Other critical raw materials identified in the report include rare earth elements, coal, tungsten, and chromium.


(1) European Critical Raw Materials Review. Memo 14.377 published May 2014. Available from
(2) USGS 2014 Mineral Commodity Summary: Phosphate Rock. Available from

Phosphorus Sustainability and How It Relates (or Doesn’t) to Rare Earths & Helium

April 15, 2014

I had a very entertaining time being interviewed for the online radio program Science For the People.   The host, Desiree Schell, really had some good questions and was even able, and willing, to try to pronounce “stoichiometry” on the air!

The piece is a bit long (1 hour?) and includes discussions with Tom Graedel (Yale) about the challenges presented by rare earth elements and with Moses Chan (Penn State) talking about helium.  The parallels are interesting, as well as the contrasts.  The P talk starts at around 42:20.

Have a listen!

Direct Link to Broadcast 


The view of P from Europe: a new report

February 3, 2013
tags: ,

A new report (“Risks and Opportunities in the Global Phosphate Market”) has just been released, analyzing the P situation from the perspective of the European Union.  (LINK ) It was prepared by The Hague Center for Strategic Studies as a lead-in to the upcoming European Sustainable Phosphorus Conference on 6-7 March (LINK).  It’s quite a thorough piece drawing on both published articles, news reports, and interviews with various experts in the P sector.  Some highlights include:

– A well-nuanced overview of the P scarcity issue, being careful to distinguish among reserves and resources, and noting the ongoing discussions and dynamic nature of these estimates.

– An assessment that the new, higher prices for P (up about 3-fold since 2007) are likely to stay high and may go higher but are very unlikely to decline in the near future.

– An analysis of the P import reliance of the US phosphate industry, which seems to be on the rise, as well as similar trends for China.  (These trends leave Europe to rely largely on imports from Russia and various northern Africa exporters, such as Morocco, Tunisia, and Jordan).

– Assessment of China’s increasing trend to consolidate its phosphate mines and fertilizer producers and to take the P situation very seriously, noting that China has listed phosphate as the country’s third most important “strategic resource”.

– Expressions of concern that so much of Europe’s P supply will need to depend on northern African supplies, given the geopolitical situations there (including controversy over western Sahara, the status of the Asad regime in Syria, and ongoing labor unrest in Tunisia) AND given that the northern Africa phosphate rock has relatively concentrations of cadmium.  Concerns are growing in Europe about the accumulation of cadmium and other metals in soils (and food?) due to fertilizer application.  Furthermore, it is likely that the metal content of remaining P reserves is higher than that in reserves that are already being exploited.

– Discussion of how water scarcity in phosphate producing countries (esp. those in n. Africa) sets up possible conflicts between water-intensive P mining operations and agricultural development, further constraining expansion of phosphate rock production.

– Elaboration of possible pathways for P recycling in Europe, noting that, in the EU, P in urban wastewater is equivalent to 1/3 of the P imported for fertilizer.

– Description of Dutch Phosphate Value Chain Agreement of October 2011 that provides a means for companies, universities, government organizations, and NGO’s  to develop, in the next two years, a market for recycled phosphate and a means for export of that which is not used for Dutch agriculture.

– A creative analysis of various scenarios for the next several decades that attempt to sketch out how the P situation will evolve depending on the relative strengths of individuals, corporations, NGO’s, and nation-states and their attitudes for cooperation vs. conflict.

Some of the best passages towards the end of the report relate to how to develop “no regrets” strategies for P:  what can be done NOW that is reasonable and sound in its own right and that will set the stage in facilitating later actions as the situation evolves.  For example: – improve agricultural P efficiency; prevent permanent dilution / loss of P; promote P recovery research and technologies; develop knowledge networks, etc.

All in all, the piece does indeed set the stage nicely for the upcoming meeting in Europe in March but also for the Kickoff Meeting of the NSF Research Coordination Network for Phosphorus Sustainability set for May 2013.  (LINK)

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