Faculty of Science

Nature’s Early Warning System: Finding the tipping point from pristine to polluted

A natural solution

Ontario’s Far North is well known for the De Beers Victor Mine and the stunning, high-quality diamonds it produces. But what many don’t know is that the thousands of kilometers of peatlands surrounding the mines are a far more precious resource. Their fresh water and ability to act as natural filter hold the key to sustainable development in the Far North.

Melanie Columbus working in the field

Dr. Melanie Columbus in the field.

“We are working with the idea that development and population growth in the far North is going to happen,” says Melanie Columbus, a Postdoctoral Fellow in the Department of Biology, Western University, who is leading a team focused on the effects of land use and climate change in Ontario’s peatlands. “We think our research can help northern communities take advantage of the inherent qualities these wetlands have, but do so in a sustainable way that protects this important and sensitive ecosystem.”

The peatlands are one, huge reactive water filter that operate somewhat like the filter on a fish tank. When water flows through it, the peat draws in the excess nutrients that are a result of increased human activity. Nutrients are consumed by bacteria, stored in the soils, and taken up by plants, preventing direct impacts to streams and rivers. Clean water released back into the ecosystem feeds plants and wildlife.

Northern communities and mining operations already discharge wastewater into the extensive peatlands found there. As communities grow, smaller settlements in particular could use the wetlands for primary water treatment saving tens to millions of dollars it would cost to build water treatment plants in the far North.

It makes good environmental and economic sense to use the natural water treatment solution the wetlands provide. But there’s a big question: how much activity can they handle?

Preserving a delicate balance

Dr. Brian Branfireun

Dr. Brian Branfireun

“It has taken thousands of years to achieve this intimate and effective balance between soil and organisms,” says Dr. Brian Branfireun, Columbus’ advisor and Professor and Canada Research Chair in the Department of Biology and Western’s Centre for Environment and Sustainability. “Climate change and increasing human activity have the potential to disrupt the peatlands ecosystem very quickly if we don’t understand their impact.”

He warns that we will see dramatic effects in the next 50 to 100 years, and not just in the North. Excess nutrients that the wetlands can’t process will ultimately end up in the waterways that connect us all.

Changes to any ecosystem show up first at the microbial level, far sooner than in vegetation or aquatic wildlife. Columbus and her team are looking at this genetic level for an early warning system that can identify the tipping point from pristine to polluted.

As scientists do, they are starting with the big questions. How does land use at the local level affect the peatlands’ ability to act as a natural water filter? Where does global climate change fit in? And more important, what is the overall effect when these two forces combine with human and industrial activity?

The team’s immediate focus is to establish baselines. “You have to know what normal looks like before you can understand the limits,” Branfireun says, explaining that they are creating a biological “fingerprint” of the microbe community, as well as developing genetic indicators of degrading capacity. If changes in biological processes are identified early enough, measures can be put in place to preserve the balance.
    
Creating a testing toolkit

Environmental research in the peatlandBig picture, Columbus hopes to have meaningful experimental results by the end of the summer. Outcomes so far lead to a testing toolkit that can actively monitor changes in the peatlands ecosystem and alert communities and industry to act before damage sets in.

“Ecosystems can be quite resilient, but only up to a point,” says Columbus. “If we can identify the proverbial edge of the cliff, that tipping point, we can develop early warning systems to better detect changes, even subtle changes that could lead to irreversible damage.” The toolkit offers a two-prong approach: measurement guidelines to collect outputs such as increased biological activity and a decision-making component to guide wastewater management planning.

For example, measurements could pinpoint the best location to construct wastewater discharge pipes and estimate the pipe’s operational lifespan. Ongoing monitoring could identify the onset of changes that might lead to damaging increases in methylmercury, nitrogen or phosphorus in downstream waters.

All of this valuable information can prevent environmentally and financially costly outcomes such as restoring a polluted wetland, or worse, reviving an ecosystem that has collapsed to the point where contaminated waters are flowing directly into sensitive aquatic ecosystems.

Future thinking

As winter melts away and spring slowly approaches the far north, the peatlands will start to come alive, sparkling like the northern jewels they are. By June, Columbus and her team will be back in the field gathering more samples to send home to their lab at Western University.

Someday soon, the team hopes to eliminate the lab altogether. Lab facilities are scarce in the North, and sending samples south for continuous testing is costly. Sensor technology -- think carbon monoxide alarm in your home - is on the horizon. This type of active, continuous monitoring could give communities and industries the information they need to sustain a delicate balance as the North grows.