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Getting The Dirt On Our Nation's Soil

They are piled on shelves, strewn across tables and tucked into filing cabinets lining the lab in Hurtig Hall, hundreds of small plastic bags of farm soil—Just don’t call it dirt.
“If you think about it, without soil, life is impossible,” explained Professor Geoffrey Davies, who co-directs the National Soil Research Project at Northeastern University. “If plants can’t grow, we won’t survive.”

The project, nicknamed NSP, aims to measure the humic acid (HA), fulvic acid (FA) and humin (HU) contents of the nation’s agricultural top soils. Davies and Dr. Elham Ghabbour—both world leaders in this field of research— work on this project with a cadre of Northeastern students who have volunteered over the years.

Scientists have long known what HA does. It’s what holds water to feed plants at a healthy rate. It’s what controls the erosive properties of soil and allows soil to act as a climate regulator. It’s what makes mud slippery. The concern is that HA levels in American soil are being depleted over time, which will impact our ability to farm or manage the landscape in the future.

But by surveying HA levels in regions around the country, Davies and Ghabbour hope to help local organizations, scientists, farmers and industry better understand current soil quality and plan for the generations to come.

“This is about our food, health and the sustainability of our way of life,” Ghabbour said.

The research started when Davies and Ghabbour came together in 1993. Ghabbour was hired in a research position at Northeastern, and connected with Davies, who has been at the University as a chemistry professor and researcher since 1971. The two pioneered a method to isolate humics from the other organic matter in soil—a process that spawned the NSP.

So far, the pair have collected and analyzed 800 samples from across the country, sometimes in partnership with organizations like the Cooperative Extension of the USDA and 4-H. The research shows HA levels vary widely not just state-to-state, but county-to-county and sample site-to-sample site. On average, American soil contains about 1 percent humic acid, but the project has found locations with none.

WATCH: WBZ-TV’s Coverage of the National Soil Project
Prof Davies and Ghabbour know they will not likely see the project to fruition, and they’re OK with that. In fact, the pair is hoping to teach the next generation of soil scientists, not just at Northeastern, but at workshops and training sessions around the country.

“We’re anxious to teach people what we do,” Ghabbour said. “We want to make them understand the importance of this work, the value of surveying the nation, our land.”
To that end, Davies and Ghabbour have taken their quest for answers to a whole new level. Davies admits he comes in on weekends to sort through soil samples and solicit soil donations from far-flung states. Ghabbour points to photos of former student researchers and brags of their successes like a proud parent. They interrupt each other in an effort to explain why soil science hits at the very heart of life.

“We learn about plant biology. We learn about plant physiology. But we forget that plants need this matrix to grow in,” Davies said. “This work is more exciting than anything I’ve come across.”

Want to help? The NSP needs 2 oz air-dried agricultural top soil samples from farms and other agriculturally active land around the country. Please send parcel post, which will be reimbursed on request. Please submit a Sample Reply Form (download) with each sample and provide GPS coordinates for the soil’s original location. The project results will be published and shared with soil donors on request.

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