The University of Delaware’s Rodrigo Vargas is a co-principal investigator on a new $18.9 million National Science Foundation grant to study soil at depths greater than anywhere else in the world. The grant is part of a NSF investment in mid-scale research infrastructure for a new Deep Soil Ecotron facility to be built at University of Idaho. 

“This facility will allow us to look deeper into the soil using state-of-the-art instrumentation under experimental settings,” said Vargas, professor of ecosystem ecology and environmental change. “The Deep Soil Ecotron will shed light on understanding how organisms and ecosystem processes of deep soils respond to global environmental change.”

Vargas and his collaborators will conduct experiments on columns of soil up to three meters deep (about 10 feet). Currently, to study soils, scientists often dig pits, which destroys the soil systems as they are uncovered. Also, most research involves just the top 30 centimeters (roughly one foot) of soil.

“So, basically, we are scratching the surface of the soil,” added Vargas. “There is a lot to be learned by going deeper.”

Michael Strickland, a University of Idaho associate professor of microbial ecology, is involved in the project.

“Deep soils are probably one of the last research frontiers,” Strickland said. “Soils are inherently important to life on the planet from supporting plants to driving processes like carbon and nutrient cycling, but a lot of research has been focused on the surface. This facility would enable us to better understand those processes at depth.” 

When complete, the Deep Soil Ecotron will contain as many as 24 “eco-units” — huge columns used to study soil cores complete with above-ground plants and below-ground organisms such as insects and microbes. Researchers will be able to control a range of variables including temperature, water and exposure to carbon dioxide and other greenhouse gases. The ecotron will be housed at Idaho’s JW Martin Laboratory with renovation expected to start in spring 2022. 

Only 13 facilities of this type exist in the world with most located in Europe. None go to the soil depths of this ecotron, giving scientists greater ability to monitor and manipulate the eco-units for controlled experiments. 

Co-lead investigator Zachary Kayler, who has conducted experiments at the ecotron in France, said the University of Idaho Deep Soil Ecotron will be a resource not only for the region but for scientists across the country and around the world. 

“This facility will represent a huge leap forward in our understanding of soil and terrestrial ecosystems — on the level of space and deep ocean exploration after similar investments,” said Kayler, a University of Idaho assistant professor of biogeochemistry. “We're facing times of uncertainty. We don’t know where the climate trends are going and can’t prepare using past knowledge. This facility will allow us to perform experiments which will help us plan for those future environmental conditions.”

Studies conducted at the ecotron will improve understanding of how deep soil organisms react to unprecedented conditions, how soil systems respond to agricultural practices and how well they sequester carbon. The eco-units will also be used to develop sensors to monitor deep soils in the field.