The leaves may have fallen outside, but inside, students in the Environmental Science and Policy program at the University of Southern Maine (USM) have been seeing green all semester long.
Students taking Dr. Karen Wilson’s Research and Analytical Methods class have spent their fall semester studying aquaponics, a system that combines conventional aquaculture — raising fish and other aquatic creatures in tanks — with hydroponics (cultivating plants in water).
In mid-November, the class of just over a dozen cultivated nine pounds of rainbow Swiss chard and five pounds of cilantro using the baby offspring of Blue and White Nile Tilapia in a symbiotic environment.
The Department of Environmental Science and Policy installed their aquaponics systems in August 2017 with a generous $25,000 gift from Poland Spring/Nestlé Waters North America and support from the Maine EPSCOR project SEANET, a network of interdisciplinary researchers along the coast of Maine to help advance sustainable ecological aquaculture.
The system is located in a newly-renovated greenhouse and attached teaching space in Bailey Hall on USM’s Gorham campus. The project is an opportunity for USM students to apply their environmental science and policy skills and obtain real-life experience maintaining and troubleshooting a complex system, said Wilson, associate research professor in the ESP program.
“Research opportunities such as the aquaponics system at USM are where our students excel: hands-on applied science,” Wilson said.
The aquaponics systems were built by Jeff Giallombardo, owner of aquaponics company Maine Agrotech, and consist of two 250-gallon setups, each with a 150-gallon fish tank attached to a “swirl tank” to filter fish waste, connected to an 18-square-foot grow bed.
The systems also include two 45-gallon fish tanks attached to two 4-square-foot grow beds.
As the water travels from the fish tanks, swirl tanks and grow beds, beneficial bacteria transform nitrogenous fish waste (in the form of ammonia) to nitrate, which is then used by plants, returning clean water to the fish tanks.
While the research-oriented class doesn’t focus on aquaponics every semester, Wilson said she, couldn't pass up the opportunity to teach the material this fall.
“As a researcher, working with students on projects such as the aquaponics systems gives me a chance to try new techniques and pursue new angles to my own research,” she said. “In this particular case, I was learning right along with them, so it really was a shared experience of discovery, success and, in some cases, failure.”
“It’s a win-win for me, and, I think, for the students,” she added.
View a feature on the students' work below. Their work was also recently featured on USM's monthly television show, "The USM Update."
Story and video by Alan Bennett, Office of Public Affairs