Gorse evaluates how much aquaculture regions can support

Graduate research assistant Libby Gorse, whose lab is in the basement of Boardman Hall at the University of Maine, is excited about research she’s spearheading for a Sustainable Ecological Aquaculture Network (SEANET) project.

She and Aria Amirbahman, professor of civil and environmental engineering, are studying the effects that aquaculture farms have on sediment below them.

Gorse, a civil engineering Ph.D. student, has been interested in chemistry and has been using chemistry lab equipment since she was a youth. Her father was an analytical chemist and Gorse followed in his footsteps and studied chemistry at Baldwin Wallace University in Berea, Ohio.

Maine EPSCoR at the University of Maine administers the SEANET project. A five-year, $20 million grant from the National Science Foundation is being utilized to learn how different types and scales of aquaculture fit into the state’s multiuse working waterfront.

Researchers will monitor the environment through field investigations, lab analysis and buoy-based sensor technology to learn about trophic dynamics of aquaculture in Maine’s coastal ecosystem.

Specifically, they’ll study how nutrients move from the physical environment into living organisms and are then recycled.

SEANET has split the state into three bioregions to study in-depth and determine how much aquaculture an area can support.

The Maine coast serves as a living laboratory, allowing researchers to explore the special feasibility of aquaculture operations.

Gorse will explore each bioregion to contribute to an understanding of the carrying capacity — what density of aquaculture operations can be maintained, what kind of sites, and how many sites are appropriate — considering local conditions.

“My study will look at the different biodeposits from oysters, mussels, finfish and all the different operations Maine supports,” she says.

“We need to grasp how to balance aquaculture operations to keep everything healthy and know how many sites or types of sites are appropriate.”

By studying the sediment below aquaculture farms, Gorse and Amirbahman seek to learn how best to advise aquaculture farmers regarding growth and placement of farms along the coast.

“It’s important to know the footprint — chemical and biological — of these farms,” Amirbahman says.

“It’s especially important for us to understand the role that these operations have on the overall nutrient budget of these systems. It will help us understand where to site — for instance how far apart from each other these operations should be. What kind of flushing rate you have, for instance — dilution via the tide or the current that can solve a lot of problems.”

Collaboration across departments

To create equipment for her study, Gorse worked with UMaine’s Advanced Manufacturing Center (AMC) to construct flux chambers to hold sediment samples.

A pump system moves water through the chambers and a chiller unit keeps the temperature of the samples at a consistent bottom water level of 45–55 degrees Fahrenheit.

John Belding, AMC director, says facility professionals and researchers collaborate to fabricate products and move research forward.

“For Libby’s project, we worked from drawings and pictures of other systems that were used at other universities,” he says.

“We came up with a design that met their needs based on what they were doing. Libby’s research is specialized, so it needed some special equipment to accomplish it.”

Belding says engineering students employed at the AMC get an opportunity to work on different parts and components of the project, from doing drafting drawings to being hands-on engineers.

“It teaches students a lot about what it means to be a project manager,” he says.

After months of testing and trial and error, Gorse’s system works just as she envisioned it. She plans to have preliminary results from the project in two to three months.

Working with stakeholders

The next phase of the study, likely in summer 2017, will be to gather samples from beneath aquaculture farms and obtain comparison samples from outside the area.

Work like this has never been done in Maine, Amirbahman says, and will be important for the next stage of research.

And, just as it’s important for various UMaine departments to collaborate, it’s key for researchers to work closely with farmers.

“We look forward to being educated and informed on the very practical aspects of this work,” Amirbahman says.

“These are aspects that you don’t read in scientific papers or books. These are people with experience. We need to get a better understanding of the impact of these facilities, especially on the environment and being able to inform them about the carrying capacity of the region.”

This research, say Gorse and Amirbahman, will help grow a viable aquaculture economy in Maine.

Contact: Andrea Littlefield, 207.581.2289