- Hi, I'm Dr. Nehemiah Mabry.

I'm an Engineer and proud graduate of North Carolina State University.

And this is the Plant Sciences Building.

It's an amazing structure.

I mean, for instance, the top floor is an entire greenhouse.

Now, there's important work happening here, all about phosphorus.

Phosphorus is a critical element.

It's essential to life as we know it.

However, we have too much of it that's running off of our crops into our waterways.

The good thing is that people here are trying to fix all of that.

In the STEPS Center.

Let's go check it out.

[bright music] - So all living things need phosphorus to grow.

It's actually required in our diet.

It's part of our nutrients.

It's stored in our bodies in the form of, mostly in bones, but it's also in our DNA.

We also use phosphorus to grow crops, so it's an essential nutrient in the food system.

And it's the nutrient in the food system that actually drives agricultural productivity, something we call yield.

In the 1940s, it was recognized that we needed to increase the productivity of the food system.

And we did that mainly, through increasing our mining of phosphates for fertilizers.

Around 1960s and '70s, we experienced the Green Revolution, which produced plant varieties and crop varieties, which also required more phosphorus to grow.

And so over the course of about 50 or 60 years, we've significantly increased our dependence on mine phosphates to feed the world's growing population.

So the United States sources most of its phosphorus from Florida and North Carolina, about 75%.

- [Nehemiah] There's actually a phosphate mine in Aurora, North Carolina, just off the Pamlico River, where they refine products for animal nutrition and for industrial fertilizer markets.

- But the way that we use phosphorus today is unsustainable.

- You need it to survive.

We need it for all living things to grow.

So we apply it to our fields, and then unfortunately, it runs off and causes these, you know, large algal blooms, some low oxygen in the water and fish kills, and really disrupts our ability to swim and clean lakes and for recreation purposes, but also for fishermen and women.

People that have seen, have driven past lakes or have been in lakes where there's these just large green blobs of stuff, and it's unappealing.

And so you can actually see the problem.

I don't know that there's a connection in people's minds that the fertilizer that we put on fields, or the wastewater that we're creating that maybe runs off into these streams, causes those large algal blooms.

- We mine the phosphorus from a non-renewable source.

We use it in fertilizer.

We put in our agriculture.

And then 80% of it is lost to our environment.

It's like going in the shower and use a shampoo bottle, and then 80% of it goes down the drain.

- [Nehemiah] The world's population is growing fast.

It's projected that we will have 10 billion people on the planet by 2050.

Scientists and engineers are working to find ways to feed all of these people more efficiently and more sustainably.

- So the vision of STEPS is something that's affectionately called 25-in-25.

It's a 25 year vision, within 25 years, to have reduced our human dependence on mine phosphates by 25%, and reduced losses of phosphorus to soils and surface waters by 25%, increasing resilience of the food system.

- Just say the magic word.

25-in-25.

25-in-25.

Jacob, what does that mean?

- So STEPS was funded as a National Science Foundation Science and Technology Center, or STC, in 2021.

With an initial grant of 25 million over five years, with an expectation for renewal.

NSF Science and Technology Centers are agency-wide, meaning that the topics sponsored under these centers should span all areas of interest of the National Science Foundation.

And the challenges underpinning phosphorus sustainability do that.

They reach all the way from material science and chemical engineering and environmental engineering, all the way over to social science and geopolitics and public policy.

And so we established a team that collaborates in a very significant deep way across all of those different disciplines, something we call convergence research.

- [Nehemiah] Darrell Harry is a PhD student in Materials Science and Engineering.

He is looking at metal oxides for phosphorus recovery.

Imani Madison recently completed her doctorate in Molecular Biology.

She's looking at how to measure plants under stress, particularly stress related to phosphorus uptake.

She shows me a 3D printer that uses living material and something called bioink.

- STEPS is a partnership with 10 institutions, with NC State as the lead.

Some other North Carolina institutions involved include Appalachian State University, UNC at Greensboro, and NCANT.

We have about 40 senior investigators and about 40 post-docs and graduate students that work across all of those different disciplines.

We have a lot of undergraduates working in the center.

And we also have a Summer Research experience for undergraduates program, that brings in undergraduates from other universities to work within our lead institution and our partner institutions.

- [Nehemiah] For decades, NC State Research Stations have been measuring plant production related to the amounts of phosphorus being applied to fields.

The North Carolina Extension Service is a partner with the STEPS Center, and is working to reach growers with best management practices.

- One of the great things about engineering at NC State, is the ability to solve society's grand challenges, and I think the STEPS Center really exemplifies that.

So taking a problem like phosphorous sustainability, which touches upon agriculture, it touches upon environment, it touches upon public policy, and looking at it with engineering eyes, while accepting that engineering isn't the only solution, right?

But engineers can bring everyone together and help address the systems level problems associated with that particular issue.

So I think, moving forward, seeing engineering do that in other spaces, spaces like climate change, for example, I think that's gonna be a wonderful opportunity in the future.