Statement of the Issue(s) and Justification: Phosphorus (P) is a critical element for life on Earth. Although P is all around us (there are more than 1 million chemical/biochemical forms), a few major P compounds are the primary nutrient source in agricultural systems. Namely inorganic phosphates in the di-hydrogen and the mono-hydrogen form. Thus, P-based fertilizers are produced in various forms to provide this critical element. Addition of P-based fertilizers increases crop yield by 30-40% in some soils. P-based fertilizers are the primary mass flow of this critical resource in current agricultural/food systems across the planet (Cordell and White, 2014).

P is primarily obtained from traditional mining activities. Of the approximate 40 Megatons of P per year which is mined for US agriculture, approximately 18 Megatons per year is used in the agrochemical industry, most of which is for fertilizer. Over-application of P fertilizer leads to reduced plant health, wastes finite resources, and can be released to receiving ecosystems which causes environmental problems. Currently, there are no large-scale systems that recover P and reuse this critical resource as fertilizer, although large efforts are underway to develop such systems. This “Phosphorus Management Problem” is a major global issue and requires detailed knowledge of stakeholder views as well as investment in new technologies for P recovery.

Stakeholder Views of Phosphorus

Meaningful solutions to the “P Problem” require an understanding of different types of stakeholder perspectives (Merck et al., 2024). Expanding on this idea, Grieger et al (Grieger et al., 2024) recently conducted a study to identify stakeholder views, needs, concerns, and challenges regarding P sustainability. The study targeted industry, government, academia, non-governmental organizations, and other civil groups, each identified as an expert within the domain of P as a resource. Based on responses from nearly 100 stakeholder participants from a range of sectors, areas of expertise, and geographies, Grieger et al (2024) conclude that the vast majority of stakeholders consider current practices for use of P to be linear, with no recovery of unused or waste P. In addition, the survey identified that stakeholders are very concerned about the ability to manage P. Stakeholder participants expressed a range of needs to improve P management systems, including:

• improved management practices;


• new technologies;


• enhanced regulations; and


• better approaches for stakeholder engagement.

The key technologies which are needed to enhance phosphorus sustainability include: enhanced predictive models ^3–5, recovery technologies for “unlocking legacy P” ^6–8, and monitoring devices (e.g., sensors, arrays) ⁹. Merck ² notes that barriers to adoption of these emerging solutions are not limited to technological but include multiple factors within the sustainability framework (economic, social, and legal factors, among others).

Deviney et al ¹⁰ recently called for coordinated stakeholder engagement with the collective aim of identifying needs and perspectives involved in sustainable phosphorus. The proposed multistate group aims to contribute a step toward filling this gap, and will collaborate with key organizations in this research area with extensive stakeholder engagement (e.g., STEPS NSF center, Sustainable Phosphorus Alliance).

Importance of Phosphorus Management

In addition to the stakeholder-driven needs delineated above, the P industry is driven by complex supply chain logistics ¹¹. The global distribution of phosphate rock in a handful of key locations, creates major concern over supply chain issues. Due to the uneven distribution across the globe and dependence on extractive mining, P fertilizer markets are vulnerable to exogenous shocks, including commodity market shocks, extreme weather events or natural disasters, and geopolitical instability (including trade disputes, disruption of shipping routes, and war). The work by Baker et al (2024) illuminates the importance of sustainable P practices for improving US resiliency, including: 

• leveraging internal P recycling loops,


• improving plant P use efficiency, and


• utilizing legacy soil P

Lowering risk related to the P supply chain is critical, as Elser et al ¹² describe a looming “phosphogeddon” (i.e., phosphorus Armageddon) if sustainable systems are not employed. Sustainable practices such as eco-prospecting, eco-mining, and eco-refining are the key to avoiding catastrophic failures in the P system.

Feasibility plan

The development of the proposed Multi-State group is built on a foundation of strong leadership and ongoing research projects that span NIFA, NSF and industry funding. The proposed project builds upon an existing Science and Technologies for Phosphorus Sustainability (STEPS) Center funded by the National Science Foundation (NSF; CBET-2019435). Expertise of initial participants are summarized below, and we have plans to grow our group by partnering with colleagues within the Multistate network. See Rationale section for details on team. In addition to our land grant participants, our group has numerous non-land grant participants that will engage with other MultiState efforts including, but not limited to, NC1194: Nanotechnology and Biosensors.

A geographical map of the personnel expertise and distribution of institutions is shown in Figure 2. Personnel expertise for the proposed Multi-State Project is described below and represents nine different departments at land grant institutions:

• McLamore (Agricultural Sciences, Clemson University) is an expert in sensors and decision support systems, and has experience as director of a NIFA CAP/Center of Excellence;


• Sozzani (Plant and Microbial Biology, North Carolina State University) is an expert in plant development, and is the Co-deputy Director of STEPS, Director for the Plant Improvement Platform at NCSU, and lead for the NSF AccelNet;


• Gomes (Mechanical Engineering, Iowa State University) is an expert in polymer systems and sensors/delivery systems. She is the site lead for the NSF Center for Soil Dynamic Technologies;


• Sahoo (Water Resources, Clemson University) is an expert in stormwater management and also watershed/water quality modeling related to P.


• Thuberty (Biology, Appalachian State University) works at the interface of local ecology and impacts of land use change on water resources, including nutrient pollution.


• Bhadha (Soil, Water and Ecosystem Science, University of Florida) is an expert in water quality, soil sustainability, sustainable agriculture and nutrient management.


• Nguyen (Tropical Plant and Soil Sciences, University of Hawaii) is an expert in plant-nutrient availability and bio-waste management.


• Porterfield (Agricultural and Biological Engineering, Purdue University) is an expert in bioregenerative systems, space biology, and non-invasive sensors.


• Diana Vanegas (Biosystems Engineering, Clemson University) is an expert in sustainable engineering, food and agricultural systems, and low resource communities.

Non-land grant participants

• Al Shipley is the CEO of Science Wares, Inc., and serves as industry advisor.


• Luther Lyle, Director, Museum of The Cherokee of South Carolina

Key attributes of multistate effort

As P is a finite resource, each state deals with supply chain and environmental issues in a unique manner. A multi-state group on P management will establish a unique perspective to be documented and shared via annual reports, impact statements, and other documents. These documents will illuminate key issues such as fertilizer supply chain challenges, state-of-the-art monitoring/recovery technology, and best practices in P management, among others. Through partnerships with an existing NSF research center focused on P sustainability (STEPS), we will expand the impact of our work and disseminate documents broadly.

Anticipated impacts

We propose to curate and document information on P management practices as well as monitoring/recovery technology development. We will also include documentation describing historical management practices to guide future efforts in agriculture. As a component of this project, we will develop an open-source database with the intent to improve stakeholder engagement.