Clemson scientists join nationwide laboratory aimed at reducing phosphorus use

Scientists at Clemson University have joined a national research effort focused on developing solutions that will make the use of phosphorus — a finite element essential to food production — more sustainable.

Science and Technology for Phosphorus Sustainability, or STEPS, is a research enterprise consisting of scientists and engineers from universities spanning the country that addresses the challenges in phosphorus sustainability by integrating contributions across scientific disciplines.

Eric McLamore and Vidya Suseela, associate and assistant professors, respectively, in Clemson’s College of Agriculture, Forestry and Life Sciences, and Hai Xiao, Samuel Lewis Bell Distinguished Professor of Electrical and Computer Engineering in Clemson’s College of Engineering, Computing and Applied Sciences, will form the core of a team that will include postdoctoral fellows, graduate students, undergraduate students and laboratory staff.

McLamore and Xiao will contribute their expertise in the development of sensors and intelligent infrastructure to the design of a handheld device that can measure phosphorus content in soil and water. Suseela, a soil ecologist, will use her understanding of the biological pathways plants use to extract nutrients from soil to help plants mine existing soil phosphorus more efficiently.

McLamore is co-director of the center’s team focused on diversity, equity and inclusion (DEI). Together with Dean Sherine Obare at the University of North Carolina A&T, this team focuses on creating and supporting a diverse and inclusive research team and workforce. In addition, this group focuses on making research data about phosphorus accessible to non-scientists and people with disabilities.  

Together these scientists will contribute to STEPS’ goal of 25 percent reduction in human dependence on mined Phosphorus within 25 years. Phosphorous is mined mainly in the U.S. (Florida), Kazakhstan, China, Morocco and Tunisia.

“Clemson brings vast experience on sensing biological signals and chemistry in complex soil systems that enable STEPS to better access legacy phosphorus in soils and optimize addition of recovered phosphorus,” said Paul Westerhoff, STEPS co-deputy director, and professor of environmental engineering in the School of Sustainable Engineering and The Built Environment at Arizona State University.

More sustainable phosphorus use could lead to enhanced resilience of food systems, less environmental damage, lower costs for food producers and a reduced dependence on a global fertilizer market that is subject to the whims of international markets and relations.

“Phosphorus is an extracted material that has a finite lifespan. As we mine it, we deplete the resource, so we must change our practices and behaviors on the agricultural side. And on the resource allocation side we must figure out ways to recover the phosphorous that we have already used,” McLamore said.

The aim of the research by McLamore and Xiao is to identify materials that can be used in sensors to make handheld devices that can be used by industry, citizen scientists, researchers, growers or Extension agents to take physical measurements of phosphorus in soil and water.

“There is a lack of reliable commercial technology for measuring phosphorus in a way that tells us where it is and what type it is. We need to be able to figure out what type of compound it is, where it is and where it’s moving to. These sensors will help us do that in soil, water and plant material,” McLamore said.

Xiao, who is chair of the Holcombe Department of Electrical and Computer Engineering, said the team is well positioned for success.

“We are working collaboratively across disciplines to create more resilient food systems and reduce environmental damage,” he said. “The sensors we are developing could prove transformational, and I am excited to be part of this project.”

Suseela’s research aims to enhance the ability of plants to access phosphorous that already exists in the soil by tapping into the capability of mycorrhizal fungi.

Mycorrhizal fungi are beneficial fungi growing in association with plant roots. Mycorrhiza describes a symbiotic association between a green plant and a fungus. The plant makes organic molecules such as sugars by photosynthesis and supplies them to the fungus, and the fungus supplies to the plant water and mineral nutrients, such as phosphorus, taken from the soil. 

“Farmers use a lot of phosphorus because it is not readily available in soil for plants. Mycorrhizal fungi are very efficient fungi that can mine the phosphorus from the soil and provide it to the plants. So, if we can tap into this capability, then we can reduce the need to add phosphorus to soil, help farmers produce more food with less cost and reduce the pollution caused when phosphorous applications end up in the groundwater and water bodies,” Suseela said.       

To enhance the DEI goals of the center, the Clemson research team will contribute to an effort to aggregate the research, Extension documents and other information about phosphorus in a Google-like platform that allows non-scientists to search for information using non-scientific language.

“It’s sort of like taking all the extension documents, as much of the peer-reviewed literature as we can, also as much information from companies as we can and put into a simple series of apps and software that people can tap into using natural spoken language just like we can use Google search, but it would be very specific to phosphorus,” McLamore said.

STEPS is also prioritizing the development of a diverse group of scientists that, according to its website, promotes “diversity in thought, culture, experience and approach toward problem solving required to address a societal issue that no single discipline or group can solve on its own.”

“A sustainable solution needs ideas from a diverse group of scientists and students. So, we work with K-12 youth all the way to faculty in terms of trying to create hiring programs, and we have a network for students who come from underrepresented groups across the universities. The next generation of scientists will likely be different than the previous generation in many ways, and we want to provide an inclusive infrastructure,” McLamore said. Other STEPS members include North Carolina State University, Appalachian State University, Arizona State University, Marquette University, RTI International, University of Florida and University of Illinois at Urbana—Champaign.