Researchers find evidence of vehicle emissions in the ecosystem
The moss in Kananaskis has a story to tell.
Researchers have used the facility to study whether nitrogen from visitor vehicles has entered the local plant population in Alberta’s provincial park.
These types of studies have been done before, but in populated areas such as European cities where vehicles move in large numbers.
At Kananaskis, researcher Ann-Lise Norman said they weren’t sure what concentrations, if any, of vehicle nitrogen they would detect in moss.
“I really thought we couldn’t get anything,” Norman said.
“We started working with nitrogen isotopes and crossed our fingers – and then 20 years later we found that it worked.”
Located west of Calgary, Kananaskis is a popular outdoor destination that many visitors access by vehicle. Driving to a trailhead for a day hike or other wilderness excursion is something many don’t think twice about.
But life scientist Mary Reid, a professor emeritus at the University of Calgary, was keen to dig deeper to understand how this norm, driving into a provincial park, might impact the environment.
As part of a field course as part of the Environmental Sciences program at U of C, researchers and students have been able to return to the same area in Kananaskis year after year and collect moss for study.
“It’s really about an underestimated component of the impact that humans have on the natural environment, and that’s the emissions generated by people’s vehicles that have access to natural areas,” Reid said.
“In what appears to be a very pristine area, are we actually seeing vehicle inputs into this ecosystem?”
Moss a natural air quality sensor
The greatest help in answering this question was already growing in Kananaskis: the moss.
Moss, Reid explained, doesn’t get its nutrients from the soil. Instead, it pulls out of thin air.
“So they can be used as biomonitors,” Reid said. “They sit out there in this environment day in and day out and we can see what they’re ingesting and use that as a measure of air quality.”
Researchers then studied nitrogen isotopes to distinguish between naturally occurring nitrogen and the nitrogen from vehicle emissions.
In 2003, when the investigation began, Alberta Transportation registered 783,400 vehicles going to Kananaskis. In 2019, when the study ended, 1.1 million vehicle trips were recorded.
Vehicle-derived nitrogen found in Kananaskis Moss
By harvesting the plant and cross-referencing the nitrogen with the province’s traffic data, a correlation was established.
While the nitrogen levels Reid said paled in comparison to some other studies, each year they moved up and down with the number of vehicles they tested.
The discovery that Moss can also detect vehicle emissions on a smaller scale is exciting, Reid said. This means that human impacts can be studied in protected areas in this way.
“Other spots might see an even bigger effect,” Reid said. “Maybe even right next door in Banff.”
Implications require more research
Reid said the next steps are now to study the potential impact that these levels of introduced nitrogen are having on the Kananaskis region.
Natural environments that introduced nitrogen could change what types of plants thrive, which may affect whether native plants can survive. It could also affect the animals that feed on these native species.
“If these areas are being protected for their natural communities that are unique or specific to that region, we really don’t want to change that and introduce more nitrogen-loving plants that are often invasive plants that come in from elsewhere,” she said.
“So we should be aware of these impacts and assess whether they are indeed changing the very thing we are trying to protect.”