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thousands of dead fish float to the surface of a Louisiana river

Can 7 billion people have clean water and plentiful food, ASU scientists ask

The Phosphorus Sustainability Research Coordination Network (RCN), a global gathering of researchers and stakeholders, will meet in Washington, D.C. May 14-16 to discuss phosphorus, a dwindling nutrient essential for food growth.

Phosphorus is found in a naturally occurring chemical compound called phosphate. Formed millions of years ago from old coral reefs and sedimentary deposits, the Earth’s current geological phosphorus supplies are intensively mined to produce modern fertilizers.

However, supplies are getting harder to find, making it difficult to maintain current agricultural and technological advances. Additionally, the world’s population continues to increase, putting added pressure on resources.  

Today, there are a few U.S. and international phosphorus mines, but the largest deposits are located in the conflicted African country of Morocco. That makes accessing future phosphorus supplies uncertain.

Due to the combination of high demand and uncertain supplies, the price of phosphorus rock used in fertilizer has skyrocketed in recent years, making it difficult for farmers in developing countries to grow their crops and support their livelihoods. Ironically, in industrialized nations, excess phosphorus waste runoff from farms pollutes rivers, lakes, and oceans. This runoff creates harmful algal blooms that create ecological “dead zones” that suffocate fish and negatively impact the fishing industry. In rivers and lakes, the phosphorus pollution contaminates drinking water.

The solution: phosphorus recycling and efficiency

The National Science Foundation-funded RCN will host the first of five annual meetings, focusing on identifying research priorities for phosphorus recycling and efficiency.

Arizona State University researcher and RCN lead investigator James Elser has been studying phosphorus and other nutrients for over 20 years. He believes if the RCN can find a way to recycle phosphorus and increase production efficiency, then our water will be clean and our food plentiful.

“If we want to have a reliable food supply, we need to have affordable fertilizer, which means we must have a sustainable source of phosphorus,” says Elser, a Distinguished Sustainability Scientist at ASU’s Global Institute of Sustainability, a Regents' Professor at ASU’s School of Life Sciences, and the lead organizer of ASU’s Sustainable P Initiative. “If we want clean water, we have to keep the phosphorus waste out. So, if we can figure out a way to recycle the phosphorus from the food system back into fertilizer, we can keep the runoff out of our water and maintain a sustainable source of phosphorus.”

Elser calls this approach “the new alchemy.”

“We need a new alchemy where we change things qualitatively,” Elser says. “We need a plan by which we can take waste and transform it into resources. We need to change dead zones into productive zones. We need to take the threat of hunger and turn it into a situation of security.”

Combining research for maximum use

A key component to the five-year Sustainable Phosphorus RCN is bringing stakeholders and scientists together to learn from one another and develop interdisciplinary solutions for phosphorus sustainability.

“Complex problems, such as that of managing the phosphorus cycle, cannot be addressed by any single discipline or interest group,” says Rimjhim Aggarwal, a co-principal investigator of the RCN, an associate professor at ASU’s School of Sustainability, and a Senior Sustainability Scientist at ASU’s Global Institute of Sustainability. “We need to create networks of scientists and practitioners who, in their normal course of work, do not generally interact with each other. The RCN provides a formal mechanism to bring these people together to work on the multiple dimensions of this problem and develop integrated solutions.”

During the first meeting, stakeholders from the U.S. Environmental Protection Agency, the World Bank, the U.S. Department of Agriculture, the U.S. Department of Energy, nonprofits, grower and livestock groups, fertilizer companies, and recycling and waste agencies will meet scientists involved in phosphorus research. These scientists come from disciplines such as ecology, social sciences, engineering, and urban planning.

“This initial meeting is the first step of the conversation among the core participants,” says Elser. “Each participant is coming to the meeting with a case study, model, expertise, and past research, but the idea is to get a lot more value out of their work by combining the research and putting facts together in new, transformative ways.”

Global implications

So what would happen if global phosphorus supplies are diminished? Because phosphorus is a naturally occurring nutrient, we can’t destroy it. However, as with any scarce resource that’s in demand, economies and lives worldwide will be affected.

“Phosphorus isn’t going to disappear; it’s going to get really expensive,” Elser says. “If it becomes very expensive, then only rich countries will have fertilizer to grow their food. But even then prices will go up and that will make it harder for farms to have economically viable operations. Farmers will go out of business. More importantly, most of the world’s hungry people are in developing nations, and they already can’t afford fertilizer. They will get hit the hardest.”

Aggarwal adds that governments around the world, especially in developing countries, heavily subsidize chemical fertilizer supplies to farmers. For now, this keeps the fertilizer prices low. However, as governments face pressure to cut their budget deficits, these subsidies will be harder to sustain.

Ironically, this one nutrient that affects all of us is getting little attention.

“Phosphorus scarcity strikes me as an issue that seriously threatens the production and accessibility of affordable food now and into the future,” says Aggarwal. “Yet we see very limited public awareness about this issue. Fortunately, ASU is uniquely positioned in terms of its long record of multidisciplinary research, as well its problem-focused and solution-oriented approach to address the phosphorus challenge.”

By the end of the RCN’s fifth and last year, Elser hopes they’ll be closer to the RCN’s goal: identifying pathways to achieve phosphorus sustainability for a secure food supply without compromising drinking water and fisheries.

“If you drink water and eat food, you should care about phosphorus,” Elser adds.

To learn more about phosphorus and ASU’s Sustainable P Initiative, watch James Elser’s presentation.