CELS Professor is at a New Frontier of Soil Science

When it comes to underwater soils, Dr. Mark Stolt has earned a national reputation as a pioneer of soil science. In fact, Stolt, a professor of Natural Resources Science at the University of Rhode Island College of the Environment and Life Sciences (CELS), continues to set worldwide standards with his research as new chapters on underwater soils are added to field guides used by soil scientists. “A lot of the literature that’s now available on subaqueous soils is literature that we developed,” he says.

Stolt really digs soils. What some people see as dirt, he sees as a whole world of knowledge waiting to be unraveled.  “People take it for granted. It’s just something that’s under their feet or something that gets them dirty,” he says. “It’s pretty much the foundation of life, as far as I can see.” From cleaning the groundwater we drink and supporting plants that provide us with food and oxygen to serving as the foundation for buildings and roads, Stolt is acutely aware of the significance soils hold as a natural resource. 

His interest in soil started at a young age. “I always enjoyed being outside,” recalls Stolt. “Probably by the time I was 16 or 17 I had a garden.” He initially pursued soil science as a vehicle for landing a job. However, he quickly developed a passion for learning about soils, from the processes that form them to their relationship with the landscape. After earning a Ph.D. from Virginia Tech and working as a soil consultant in Alabama, he joined the faculty at Auburn University. A short time later, he accepted a position in the CELS Natural Resources Science Department, where he’s been for over 20 years.

Stolt has led a variety of research projects at CELS, which have explored the pressing environmental issues of today. Those challenges have ranged from studying carbon sequestration of soils in forests and wetlands to using soils to investigate salt marsh loss in the face of sea level rise. Stolt and his lab are also at the forefront of researching subaqueous soils, or underwater soils that are typically found along the coast.

“When we started this work, they thought it was crazy that we would call these soils,” says Stolt, noting just how little was known about subaqueous soils. In addition to uncovering more information about the processes that form underwater soils, Stolt became the first scientist to classify, interpret, and map them. That prompted researchers around the globe to become more interested in his work, recognizing the benefit of understanding these types of soils better.

The underwater soil interpretations Stolt developed have wide reaching implications for the aquaculture industry. “We see that a lot of the folks who are doing aquaculture now are taking our maps and saying, ‘okay, this is where I want to lease my part of the estuary to do my aquaculture,’” Stolt notes. People interested in farming shellfish look for soils with less acidity, which is harmful to immature shellfish. It’s something that is especially important as aquaculture continues to grow and ocean acidification from increased carbon dioxide emissions becomes a more prevalent threat to that industry.

Underwater soils play important roles in the development of ecosystems along the sea floor; different types of underwater soil can greatly influence where different animals and plants can be found. This has significant implications for restoration efforts in response to the die off of aquatic plants in recent years due to human impacts like pollution. “Eelgrass is a very important part of the ecology of shallow estuaries,” Stolt explains. “There’s a lot of interest in restoring the eelgrass so we were looking at what are the best soils to essentially restore it,” he says.

As Stolt and his lab’s research on underwater soils continues to grow, one thing remains clear: our understanding and value of soils is critical to the environmental challenges we face, from the effects of climate change to the impacts of pollution. According to Stolt, there’s also a huge demand for this type of knowledge in the workforce and he offers this advice to students. “A thorough understanding of soils, the processes, and how they’re distributed across the landscape can be valuable for anyone who wants to work in the environmental field and make our Earth a better place.”