In the Faculty of Science at the University of Waterloo, training the next generation of scientists about the importance of sustainable research is a top priority. Making a difference through research is Dr. Tonya DelSontro’s Aquatic Greenhouse Gas Dynamics Lab, which tracks methane levels in local inland waters.
Assisting Dr. DelSontro with monitoring local reservoirs for methane gas emissions is fourth-year Earth Sciences student, Joey Ruck. As part of his summer research assistantship and senior thesis project, Ruck is investigating the use of a scientific echosounder to estimate gas accumulation in sediments of the Belwood Reservoir.
“Most inland waters and wetlands are supersaturated with methane, meaning they are constantly releasing this powerful greenhouse gas,” says Ruck. “With the ongoing climate crisis and increased nutrient loads in waterways, methane emissions are rising every year.”
An echosounder measures methane emissions by using high-frequency acoustic signals that scatter off methane bubbles rising from the water. The echosounder’s receiver detects the sound waves that bounce back from the gas bubbles. By analyzing the returning echoes, Ruck can measure the size and concentration of the bubbles, which is used to calculate gas flux (the amount of methane released).
As temperatures rise, methane bubbles become more abundant in inland waters because gas solubility decreases with increasing temperature. But in the Belwood Reservoir, there’s an additional factor at play with managed water level reductions each fall that consequently lower the hydrostatic pressure and cause more bubbles to be released from the sediments below.
“It’s interesting to see how the data we collect connects directly to what’s happening in the environment,” says Ruck. “By studying methane bubbling in real time, we’re learning how small changes, like dropping water levels, can have big impacts on greenhouse gas emissions.”
Ruck relates the methane bubbling to the acoustic signature of the sediments as well as other sediment characteristics such as water content, organic carbon content and particle size. His work will help the lab build a model that better reflects the methane bubbling in this system that can then be replicated for other reservoirs. This research is essential to understanding how climate change is impacting the levels of methane being released from Ontario’s freshwater systems.
Thanks to undergraduate research opportunities available to Science students at Waterloo, Ruck is contributing to climate science while gaining the hands-on experience he needs to become a field-based geophysicist.
“This project gave me the chance to take what I’ve learned in the classroom and directly apply it in the field,” he says. “My experience at Waterloo is equipping me with both the technical knowledge and hands-on skills I need to study our environment and make a real difference in protecting our planet.”