Pollution the presence of harmful substances (chemicals) in the environment these potentially harmful chemicals are called pollutants they change the make up and balance of our environment acidic oceans (2 min)

Great Pacific Garbage Patch 7 min

How Much Pollution? Consequences of Pollution?

Biological Indicators the “canary in the coal mine” used to check OVERALL environmental quality we use “indicator species” which are sensitive to pollution or other changes in their environment

Biological Indicators for Water Quality Stonefly Nymph Mayfly Dragonfly Amphipod Crayfish Snails Leeches Aquatic Plants & Algae

Biological Indicators for Soil Quality Earthworms Nematodes Ants & Termites Fungi

Biological Indicators for Air Quality Lichen Plants Birds

Monitoring Water Quality

Dissolved Oxygen (DO) –oxygen gas which is dissolved in water –higher levels are found in cool, moving water DO > 5 ppm is optimal for fish –DO < 2 ppm: fish will be stressed –DO < 1 ppm: fish die

What affects Dissolved Oxygen? (mg/L = ppm) As temperature, sediment load, amount of green plants/algae, number of living organisms in a water body GOES UP… the amount of dissolved oxygen in the water body GOES DOWN.

Acidity –rain with a pH lower than 5.6 is considered acid rain –lakes in Alberta have a pH of about –acid rain can change pH of surface water and soil, damaging or killing plants, fish, etc. most fish will die if the pH falls to 4.5 ocean acidification (21.5 min)

Phosphates & Nitrogen –nutrients that enter the water through runoff from sewage and fertilizers –can cause increase in algae and other green plants in water reduces dissolved oxygen, blocks sunlight, aquatic life dies off Effluent

Pesticides –can result in pesticide-resistant pests –can contaminate soil, water or food –can kill ‘unintended’ organisms –bioaccumulation (biomagnification) can affect organisms higher up in the food chain Heavy Metals –some elements are toxic even in small amounts (e.g. mercury, lead, zinc) –they can cause abnormal development, brain damage or even death –often last a long time in the environment and will bioaccumulate in organisms

Turbidity the “cloudiness” of the water caused by suspended sediment load most aquatic organisms prefer fairly clear water

Monitoring Air Quality clean air is mainly N (78%) and O (21%) air quality can be affected by chemicals & particulates (e.g. dust) air quality can be determined 2 ways: –by measuring actual levels of pollutants in the air –by estimating the amount of emissions from pollution sources

Air Pollution many (most) air pollutants come from the burning of fossil fuels (cars, factories, electrical generation stations, etc.) air pollutants affect our respiratory system and irritate our eyes… and worse air pollutants impact plant growth, animal health, change the pH of lakes and oceans, degrade plastics, weaken building materials, etc.

SO 2 – sulfur dioxide –sulfur + oxygen → sulfur dioxide –forms smog and acid rain –“scrubbers” use limestone to capture sulfur emissions before they are released NO x – generally NO or NO 2 –contribute to smog and acid rain –NO 2 gives smog its distinct browning colour CO – carbon monoxide –silent killer (colourless & odorless gas) O 3 – ozone –when found near the ground ozone reacts with other chemicals to form VOCs (organic chemicals)

Greenhouse Gases CO 2 (carbon dioxide) is a greenhouse gas which contributes to global warming –produced mainly from burning fossil fuels –before industrial revolution CO 2 levels were ~ 275 ppm … today they are ~ 350 ppm

the ozone layer has thin areas or holes where to much UV light can come through –cause skin cancers and cataracts –cause plankton (a main marine food source) to die one big cause of the problem are CFCs (chlorofluorocarbons) which are used in –refrigerators, aerosol cans, fire extinguishers

Holes in the Ozone Arctic View