Scientists will be prevented from entering the Experimental Lakes Area at the end of the month, ending several long-term experiments aimed at keeping fresh water clean and Canada's environment healthy.
Here are four studies that will be stopped before they are completed:
ELA Climate Study
What the experiment was trying to determine: The changes to lakes and the fish populations they support in the drier conditions that are predicted as a result of climate change. This experiment focused on the health of lake trout, a cold-water fish species known to be sensitive to human disturbance.
What was being done to the lakes: Water was diverted around a lake that is fed by three upstream lakes, isolating it from its original watershed and reducing the inflow by 80 per cent. This was achieved by construction of a large diversion channel blasted through bedrock to reroute the water.
How long the experiment has been conducted: The lake was monitored for three open-water seasons starting in 2008. The manipulation of the water started in the fall of 2010.
What researchers hoped to do this year: Researchers were planning to continue their research programs, such as examining the drying of downstream wetlands, conducting a hydro-acoustic assessment of fish communities and assessing the habitat changes of the lake trout.
What will be lost: Scientists were just beginning to see changes to the lake and fish communities. The experiment needs to continue for several more years to truly understand how lakes respond to climate change. Scientists will lose the ability quantify and predict the consequences of climate warming to lakes and to cold-water fish populations.
METAALICUS (Mercury Experiment to Assess Atmospheric Loading in the United States and Canada)
What the experiment was trying to determine: How much mercury concentrations in rainfall need to be lowered so that the concentrations in fish are low enough for safe consumption by humans and wildlife.
What was being done to the lake: Small amounts of mercury were added to a lake and its watershed to simulate the elevated mercury concentrations in rain caused by the combustion of coal in power plants.
How long the experiment has been conducted: Fifteen years. Scientists were hoping to continue for at least two more decades, because the mercury added to the watershed is taking a very long time to work its way into the lake. Mercury is added to the lake in a form (stable isotopes) that enables researchers to follow its fate for many decades.
What researchers hoped to do this year: Experimental mercury additions to the lake and watershed have stopped, but scientists are studying the rate of recovery by continuing to sample mercury in the fish in the lake and in the stream flows coming off the watershed.
What will be lost: Scientists will not be able to determine how long it will take lakes (and fish) to recover after mercury concentrations in rainfall are reduced by controls on mercury emissions from coal combustion. The million-dollar investment in the mercury isotopes will not be fully realized.
What the experiment was trying to determine: To test the claims of detergent companies that carbon, and not the phosphorus in their products, was responsible for algae blooms in lakes and the related problems of reduced oxygen, toxins and the death of fish.
What was being done to the lakes: A lake that is shaped like an hourglass was partitioned at the narrows with a curtain. Nitrogen and carbon were added to one side and phosphorus to the other. The picture of the algae bloom that emerged on the phosphorus side convinced policy makers around the world that phosphorus was the culprit. Other experiments in ensuing decades tested the effects of elements like nitrogen and iron.
How long the experiment has been conducted: Forty-five years. This year was to be the last, but the researchers say fertilization of the lake should be maintained to allow the study of new and emerging problems.
What researchers hoped to do this year: The study is looking at other things such as why iron-poor lakes of the Prairies do not recover as quickly the iron-rich lakes of the Canadian Shield when phosphorus is removed.
What will be lost: The only area in the world where inputs of nutrients, other chemicals and food chains can be closely controlled in a watershed.
What the experiment was trying to determine: Silver nanoparticles are an emerging contaminant found in hundreds of products, especially textiles, because of their anti-bacterial properties. Some washing machines are built to put silver nanoparticles into the load. Scientists want to learn their effect on the environment.
What was being done to the lakes: A whole lake was being prepared to have silver nanoparticles dripped into it. Last year, scientists determined the doses. They also assessed the original state of the lake to be used as a base of reference for any changes.
How long the experiment has been conducted: One year, but that was mostly preparation. The real work was to have started this year with results in 2014.
What researchers hoped to do this year: Start dripping silver from the side of the lake and monitoring the effect.
What will be lost: Canadians and their policy makers will not know the effect of silver nanoparticles on the environment.