EXPERT ADVISORY: Aug 21 2023 – R0071

Out-of-control wildfires in British Columbia and the Northwest Territories are not only destroying properties but also altering natural environments and calling attention to the ways natural disasters are handled, say Brock University environmental researchers.

While poor air quality is an easily recognizable impact, “the effects of these fires on water quality are quite profound,” says Assistant Professor of Chemistry Vaughn Mangal.

Forests hold large quantities of organic carbon and chemical compounds such as nitrates and phosphates that are nutritious for plant life, but also contain contaminants like mercury and cadmium that are harmful for plants and human health.

Mangal says forest fires can transport mercury to aquatic systems. Along with inputs of organic carbon and nutrients, microorganisms can create a chemical called methylmercury, a neurotoxin to humans and animals that can accumulate in fish across water sources.

The physical debris from forest fires also changes the types of carbon found in aquatic systems, says Mangal.

“For example, when ash settles and debris deposits onto the water, it increases the carbon and contaminant presence in the water causing the water to be darker, more turbid and more odorous,” he says.

This increased organic carbon in the water can lead to the growth of algae blooms that remove much-needed oxygen from water and can also produce more greenhouse gases, further contributing to climate change, he says.

Also contributing to greenhouse gases is carbon being released from thawing permafrost, says Professor of Geography and Tourism Studies Michael Pisaric.

Permafrost, or ground that is permanently frozen from one year to the next, is a dominant feature of Canada’s North.

“Forest fires burning in regions underlain by permafrost disturb the vegetation cover, hastening permafrost degradation and thaw,” says Pisaric, adding that carbon trapped in permafrost decomposes when thawed.

Intense fires burn more deeply into the organic layers of soil, which makes soil less porous, he says. This affects the ability of soils to effectively channel water into the ground, potentially impacting the types of vegetation that can re-establish after a fire.

In some cases, fires are recurring so frequently in recent decades that some long-lived vegetation types are not able to establish and reproduce before the next fire occurs, Pisaric says.

“Studies near Yellowknife and in parts of Yukon Territory are showing that in severely burned areas, some of the typical conifer species that characterize Canada’s boreal regions are having difficulties re-establishing following these severe fire events due to the increased moisture stress that occurs in these severely burned areas,” he says.

Residents in the Northwest Territories and British Columbia are grappling with the impacts of having to flee their homes on short notice, putting the spotlight on how authorities deal with forest fires.

“The transfer and co-ordination of authority and management between the local and provincial levels is challenging, as it is negotiated in real time and as the situation is extremely unpredictable,” says Associate Professor of the Environmental Sustainability Research Centre Julia Baird.

Baird, Canada Research Chair in Human Dimensions of Water Resources and Water Resilience, and her colleagues conducted research on major wildfires in Alberta and Sweden.

“What we learned was that it is really important to build relationships in advance of an emergency, as those relationships yield benefits when needed — for example, an emergency responder can capitalize on existing connections and very quickly have the necessary information to a critical question,” says Baird.

She says clear procedures with built-in flexibility can support the scale-up of an emergency response.

“Evacuation and meeting the physical needs of evacuees is interconnected with logistics and supply, as the needs of the evacuation centres and resources available are constantly in interplay and offers of assistance must be co-ordinated with need levels,” Baird says.

“Another example is the task of communication to the public and evacuation, where those being evacuated need timely information about where to go, and the information itself depends on capacity and fire forecasts.”

Brock University Assistant Professor of Chemistry Vaughn Mangal, Professor of Geography and Tourism Studies Michael Pisaric and Associate Professor of the Environmental Sustainability Research Centre Julia Baird are available for media interviews on the topic.

For more information or for assistance arranging interviews:

* Maryanne St. Denis, Manager, Content and Communications, Brock University mstdenis@brocku.ca or 905-246-0256

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