Aquatic Pollution in Canada Revision

8/8/2019 Aquatic Pollution in Canada Revision

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Aquatic Pollution in Canada

BIOL 4350

Bryce Pippy

0570460

September 27th

, 2010


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Canada is home to a vast reservoir of fresh water, much of it situated within the

numerous lakes and rivers that adorn the country. Not only have these lakes provided a

readily available supply of water for commercial and industrial use, but they also absorb

the waste products from many of these same processes, deliberately or accidentally.

While the huge volume of these water systems will delay major degradation, over time

damage to the waterways will become more noticeable, and more severe. Aquatic

Pollution is a very general term, and there are a number of ways that pollutants could

enter an ecosystem ranging from directly to indirectly, though regardless of the method of

entry, the contamination of waterways in Canada is a serious matter.

The most direct form of pollution occurs when harmful substances are released

into a water system from a single site or event, causing potential damage to plant and

animal life in the immediate vicinity. Because the contaminants can be linked to an

identifiable location or occurrence, it is referred to as a point source. This can occur in

many different situations, some examples of which being near industrial sites or cities

with inadequate sewage systems (Environment Canada 2010). The damage done to the

surroundings will depend on the nature of the pollutant. For example, Acid Mine

Drainage (AMD), where sulphur compounds in the rock are oxidized, often by bacteria,

into acidic forms, can induce a severe drop in pH levels in water bodies near the point of

impact, which is often close to a mining operation (Eba Engineering Consultants 2004).

Note that AMD can occur naturally through the oxidation of rocks (called Acid Rock

Drainage, or ARD), in which case it wouldnt be a point source contaminant. The waste

products can also be carried downstream to other locations, spreading the pollutants over

a wider area, an potentially affecting a greater number of ecosystems. Because the

contamination can often be traced to its source, it should be possible to treat and prevent

further contamination, provided that the source of the pollution is known. As a result,

provided there is the desire to monitor the quality of the water, and that the technology

exists to treat or eliminate the waste being deposited; this kind of pollution should be

largely preventable.


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Unlike point sources it is not always possible to track down the source of

contaminants to an exact occurrence. Non-point sources involve the introduction of

pollutants from more widespread sources, such as agricultural runoff into streams, which

is a significant problem in Ontario and farmland areas. Fertilizers and manure often

overload the water with nutrients, potentially upsetting the balance of organisms within a

community, while the pesticides often prove particularly toxic to fish and amphibians,

among other species. Agricultural runoff is also responsible for the infamous dead

zones; sections of the ocean that are devoid of life as a result of massive algal blooms

(Anderson et al. 2008). These algal populations erupt each year as nitrogen rich fertilizer

floods in from nearby rivers. The algae then exhaust the nutrients and die off, their

decomposition using up the oxygen content of the water and leaving other organisms to

asphyxiate (Anderson et al. 2008). A second example of non-point source pollution is

mercury contamination, a natural process where mercury is deposited from atmospheric

sources (such as volcanic emissions) across great distances and into water systems

(USGS 2000). Certain human processes, such as mining and, historically, pulp and paper

plants, can also contribute to the accumulation of mercury in lakes and streams (USGS

2000). Mercury is a very toxic metal, particularly when in an organic form (namely

methyl-mercury), and it can persist for a long time. Because non-point sources can arrive

in the environment from multiple, less defined sources, it is very difficult to prevent

contamination without inhibiting the process that is causing it (a difficult or impossible

task), although treatment of already contaminated waters is possible, provided that there

is knowledge of the nature of the pollutants.

In some cases, aquatic systems can even be affected by pollution that does not

directly contact the water. The production of gaseous pollution (ie smoke) containing

sulphur dioxide and nitrogen oxides is known to react with moisture in the atmosphere

and create acidic compounds, which can then return to earth in the form of acid rain

(Environment Canada 2010). Acid rain is extremely devastating to aquatic ecosystems;

the input of sulphur can dredge up metal compounds from the soil, such as mercury,

which, as mentioned, is extremely toxic (Hickley 2009). Additionally, acid rain decreases

the pH of the water, which can greatly affect organisms in the ecosystem (Environment


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Canada 2010). Similar to non-point source pollution, one cannot prevent the entry of

contaminants into a vulnerable waterway; the only way of avoiding pollution is to

eliminate the source of the contamination, which is often difficult to manage, though not

impossible, as some initiatives have made progress in combating such problems as acid

rain and nutrient runoff.

The effects of pollutants entering our lakes and rivers can be greatly varied,

depending on the situation and the chemicals released, however, it always merits

investigation, and often gives cause for concern. Much effort has been placed in

controlling the dumping of hazardous materials into natural systems from many angles;

the Nutrient Management Act was passed with the intention of reducing the effects of

runoff from agricultural systems (Ministry of the Environment 2007), while the Air

Quality Agreement between Canada and the United States addressed the reduction of

sulphur and nitrogen oxides in air pollution in order to limit the occurrence of acid rain

(Environment Canada 2010). Despite our successes in eliminating water pollution, new

manufacturing techniques and new developments will continue to bring new sources of

contamination, and the issue of water pollution will always be present.


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References:

Anderson D, Glibert P, Burkholder J. 2008. Harmful algal blooms and eutrophication:

Nutrient sources, composition, and consequences. Estuaries and Coasts. Vol. 25(4): 704-726.

Eba Engineering Consultants Ltd. 2004 April. Heavy Metals and Acid Rock Drainage: ASelect Literature Review of Remediation and Recommendations for Applied Research

[Internet]. Whitehorse, Yukon: Mining Environment Research Group; [cited 2010 Sept

27]. 21 p. Available from:http://www.geology.gov.yk.ca/pdf/MPERG_2004_2.pdf

Environment Canada. 2010. [Internet]. Gatineau, Quebec: Environment Canada;

[Updated 2010 Jul 9]. Available from: https://www.ec.gc.ca/

Hickley, ES. 2009. Biogeochemical and hydrologic sulphur dynamics in an agricultural

system. Ann Arbor (MI): Stanford University. 148 p.

Ministry of the Environment. 2007. [Internet]. ON: Queens Printer for Ontario; [updated

2008 Oct 21]. Available from:http://www.ene.gov.on.ca

NRDC (National Resources Defense Council). 2007. Getting Mercury Out of PaperProduction [Internet]. New York (NY); [cited 2010 Sept 27]. 1 pg. Available From:

http://www.nrdc.org/cities/living/mercury.asp

USGS (United States Geological Survey). 2000. [Internet]. Reston, VA: USGS National

Center; [updated 2009 Feb 19]. Available from:http://www.usgs.gov/mercury/
http://www.geology.gov.yk.ca/pdf/MPERG_2004_2.pdfhttp://www.geology.gov.yk.ca/pdf/MPERG_2004_2.pdfhttp://www.geology.gov.yk.ca/pdf/MPERG_2004_2.pdfhttps://www.ec.gc.ca/http://www.ene.gov.on.ca/http://www.ene.gov.on.ca/http://www.ene.gov.on.ca/http://www.nrdc.org/cities/living/mercury.asphttp://www.nrdc.org/cities/living/mercury.asphttp://www.usgs.gov/mercury/http://www.usgs.gov/mercury/http://www.usgs.gov/mercury/http://www.usgs.gov/mercury/http://www.nrdc.org/cities/living/mercury.asphttp://www.ene.gov.on.ca/https://www.ec.gc.ca/http://www.geology.gov.yk.ca/pdf/MPERG_2004_2.pdf

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Aquatic Pollution in Canada Revision