Study finds nitrogen has polluted remote lakes

If you ever wanted to visit a pristine Arctic lake, you’re probably about 100 years too late.

REGINA — If you ever wanted to visit a pristine Arctic lake, you’re probably about 100 years too late.

A study involving 13 universities and research institutes, including two from Canada, has found nitrogen resulting from human activities has polluted remote lakes throughout the northern hemisphere for more than a century.

Simply put, burning fossil fuels and using agricultural fertilizers increases the amount of nitrogen in the atmosphere.

The gas finds its way into lakes through rain or snow.

“Normally you’d think (gases would) be diluted in the vast quantity of atmosphere.

“There just wouldn’t be a clearly measurable signature,” said Peter Leavitt, a professor at the University of Regina, who was part of the study.

“And that’s what’s so surprising about these studies.

“Even in sites that are thousands of kilometres away from everything, we’re seeing evidence of this atmospheric pollution, when there’s just nothing around there in any direction that could have caused it.”

The scientists, who also included researchers from the University of Alberta, measured the chemical composition of bottom deposits in 33 lakes from Colorado to the High Arctic and as far away as Norway.

Leavitt, who is the Canada Research Chair in Environmental Change and Society at his university, said the project was like aquatic archeology.

The scientists shoved a plastic tube into the mud at the bottom of a lake and pulled it out.

They divided the tube into sections and estimated the age of each section by looking at the radioactive particles that occur naturally in the atmosphere.

Newer material is at the top and older material at the bottom.

Leavitt said more than three-quarters of the lakes showed signs of human-made nitrogen.

“The interesting wrinkle here is most of the lakes, particularly the ones in Canada, well up north of 60 (degrees latitude), are all thousands of kilometres from the nearest source of pollution,” he said.

“It’s not that somebody walked over and dumped nitrogen into the lakes.”

Researchers warn such global nitrogen pollution may interact with climate change to produce a double whammy that could alter remote lakes in ways not seen in the last 10,000 years.

“This is saying that humans have had effects for over a 100 years in some of the most remote ecosystems on the planet.”

The study appears in today’s issue of the journal Science.

Leavitt also said if the changes in remote lakes were due to climate or local effects, there would have been a difference in when the nitrogen started to show up. That’s not the case.

“The other piece of this that’s important is that the timing is virtually identical in all the lakes — about 110 years ago…just after the second industrial revolution. That’s when you see the signature of the change in all the sites,” he said.

“They’re all doing it at exactly the same time, which is consistent with the atmosphere fundamentally changing.”

The input of nitrogen into the lakes changes the microbes that regulate greenhouse gas emissions, take gases out of the atmosphere and cycle nutrients. Leavitt calls them the “the building blocks of the food web in the lake.”

“We don’t know that it’s changed to this point, but certainly we’re seeing evidence that…the foundation of the food web is starting to change. And usually when you change a foundation, like in an earthquake, when the foundation starts shaking, it’s not good news.”

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

There were six additional deaths across Alberta reported over the past 24 hours, bringing the death toll to 1,926 since the beginning of the pandemic. (File photo)
AstraZeneca vaccine is ready to be used at a homeless shelter in Romford, east London, Wednesday, Feb. 3, 2021. THE CANADIAN PRESS/AP-Frank Augstein
AstraZeneca-linked blood clot confirmed in Alberta

A case of an AstraZeneca-linked blood clot has been confirmed in Alberta,… Continue reading

The Red Deer Catholic Regional Schools Board of Trustees selected the name St. Lorenzo Ruiz Middle School to be built in the north end of Red Deer. (Photo Courtesy of  Red Deer Catholic Regional Schools)
Red Deer Catholic Regional Schools raises about $8,720 for Terry Fox Foundation

Red Deer Catholic Regional Schools raised about $8,720 for the Terry Fox… Continue reading

A nurse gets a swab ready at a temporary COVID-19 test clinic in Montreal, on Friday, May 15, 2020. Health Canada has reversed course on home test kits for COVID-19, saying it will now review applications for such devices. THE CANADIAN PRESS/Paul Chiasson
Alberta declines Ontario’s request to send health-care workers

Alberta is “not in a position” to send health-care workers out of… Continue reading

The Red Deer Rebels allowed four straight goals from the Medicine Hat Tigers Friday night on the road. (Photo by Rob Wallator/ Red Deer Rebels)
Tigers hand Red Deer Rebels 10th straight loss

Tigers 4 Rebels 2 Through 17 games in the shortened WHL season,… Continue reading

Red Deer Public Schools will not pilot the new draft curriculum at its elementary schools. (File photo contributed by Red Deer Public Schools)
UPDATED: Red Deer Public Schools says no to piloting new curriculum

Alberta Teachers’ Association support school boards

Ontario Premier Doug Ford points on a COVID-19 caseload projection model graph during a press conference at Queen's Park, in Toronto, Friday, April 16, 2021. Ontario was set to backtrack on controversial new police powers to enforce stay-at-home orders implemented in the battle against COVID-19.THE CANADIAN PRESS/Frank Gunn
Ford backtracks on new police COVID-19 powers amid intense backlash

TORONTO — Furious criticism of new anti-pandemic powers that allow police in… Continue reading

The official program for the National Commemorative Ceremony in honour of Prince Philip, The Duke of Edinburgh, sits on an empty pew prior to the ceremony at Christ Church Cathedral in Ottawa on Saturday, April 17, 2021. THE CANADIAN PRESS/Sean Kilpatrick
Prince Philip remembered as ‘a man of great service’ during Canada’s memorial service

Canada’s commemorative ceremony in honour of the late Prince Philip offered a… Continue reading

CF Montreal head coach Wilfried Nancy speaks to his players during the team's practice Tuesday, March 16, 2021 in Montreal. THE CANADIAN PRESS/Ryan Remiorz
CF Montreal puts on a show, defeating Toronto FC 4-2 in MLS season opener

FORT LAUDERDALE, Fla. — CF Montreal, carving open Toronto FC’s defence, cruised… Continue reading

Demonstrators using umbrellas as shields approach a point in a perimeter security fence during a protest over the fatal shooting of Daunte Wright during traffic stop, outside the Brooklyn Center Police Department, Friday, April 16, 2021, in Brooklyn Center, Minn. (AP Photo/John Minchillo)
Journalists allege police harassment at Minnesota protests

Some journalists covering protests over the police fatal shooting of Daunte Wright,… Continue reading

A container ship is docked in the Port of Montreal, Wednesday, February 17, 2021 in Montreal.THE CANADIAN PRESS/Ryan Remiorz
Montreal dockworkers begin weekend strikes as talks drag on

MONTREAL — Dockworkers at the Port of Montreal kicked off a series… Continue reading

Brad Dahr, 53, is facing numerous charges. (Photo contributed by Alberta RCMP)
Alberta man charged for alleged sexual offences against children

An Edmonton man has been charged for alleged sexual offences against children… Continue reading

A person walks past a COVID-19 mural designed by artist Emily May Rose on a rainy day during the COVID-19 pandemic in Toronto on Monday, April 12, 2021. Employment lawyers say flouting COVID-19 public health orders when off the job or coming into work while knowingly sick could warrant discipline in the workplace. THE CANADIAN PRESS/Nathan Denette
Risky pandemic behaviour off the clock could mean workplace discipline: lawyers

CALGARY — Employment lawyers say flouting COVID-19 public health orders when off… Continue reading

Vials containing Russia's Sputnik V vaccine for COVID-19 are seen at the San Marino State Hospital, in San Marino, Friday, April 9, 2021.  THE CANADIAN PRESS/AP-Antonio Calanni
China, Russia using their COVID-19 vaccines to gain political influence

OTTAWA — China and Russia have been using their locally produced COVID-19… Continue reading

Most Read