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PollutionPollutionPHSciencePHScience

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ChallengeChallenge• To define pollution;To define pollution;• To determine threats to our To determine threats to our

air/water/land resources;air/water/land resources;• To develop solutions to some of To develop solutions to some of

these problems using SCIENCE!these problems using SCIENCE!

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Background• The The biosphere (where all (where all

life exists) is polluted via life exists) is polluted via each of its parts and each of its parts and their interaction:their interaction:– the atmosphere (air the atmosphere (air

layers) layers) – the lithosphere (soil the lithosphere (soil

and rocks);and rocks);– the hydrosphere the hydrosphere

(watery & icy (watery & icy regions);regions);

– and the ecosphere and the ecosphere (plants and animals). (plants and animals).

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ContaminationContamination• Contamination is the abnormal presence of a harmful Contamination is the abnormal presence of a harmful

substance in an environment;substance in an environment;• E.g. Selenium metal is necessary in low dosages, but in E.g. Selenium metal is necessary in low dosages, but in

high dosages it is toxic;high dosages it is toxic;• The Toxicity Threshold is the level of concentration The Toxicity Threshold is the level of concentration

above which an contaminant causes one or more above which an contaminant causes one or more harmful effects in an organism. harmful effects in an organism.

• The The Lethal Dose is the amount of contaminant needed is the amount of contaminant needed to kill an organism.to kill an organism.

• The LDThe LD5050 is the amount needed to kill 50% of a is the amount needed to kill 50% of a population.population.

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LithosphereLithosphere• The lithosphere is the hard shell of The lithosphere is the hard shell of

the Earth, consisting of the crust and the Earth, consisting of the crust and the topmost part of the upper the topmost part of the upper mantle.mantle.

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MineralsMinerals• Minerals are solid inorganic substances with Minerals are solid inorganic substances with

clearly defined composition and properties;clearly defined composition and properties;• Rocks are solids that are made of different Rocks are solids that are made of different

proportions of minerals.proportions of minerals.• Granite is a rock that can have different Granite is a rock that can have different

concentrations of the minerals: concentrations of the minerals: - feldspar (red), quartz (white) and mica - feldspar (red), quartz (white) and mica (black)(black)

• An ore is a rock that contains enough of a An ore is a rock that contains enough of a mineral deposit to be mined commercially – mineral deposit to be mined commercially – for PROFIT. for PROFIT.

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RocksRocks• Rocks are classified according to their:Rocks are classified according to their:

– Density – mass/volume;Density – mass/volume;– Hardness – Mohs Scale;Hardness – Mohs Scale;– Colour – colour of rock on the inside;Colour – colour of rock on the inside;– Streak – of colour on a porcelain tile;Streak – of colour on a porcelain tile;– Transparency – how you can see thru’ it;Transparency – how you can see thru’ it;– Acid test results – does HCl make it bubble;Acid test results – does HCl make it bubble;– Origin – sedimentary, igneous, Origin – sedimentary, igneous,

metamorphic;metamorphic;

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Soil• Soil is the mixture of

– Organic matter – decomposing plants and animals;

– Minerals;– Broken-down rock material;

• The 5 soil horizons or layers are:– Organic matter/humus;– Topsoil;– Subsoil;– Fragmented parent rock;– Unaltered parent rock (bedrock);

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Life in the Soil• For soil to support life it must have:

– A sufficient amount of dissolved minerals;

– Enough moisture;– A good soil pH of 6-7 that is neither too

acidic (pH 1-6), nor too basic (pH 8-14);oSoil acts as a buffer/cushion so that its

acidity does not change too much;

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Fossil Fuels and the Fossil Fuels and the Atmosphere• Fossil fuels result from the transformation of organic residue like plants, animals;

• These energy resources consist of:– Oil;– Natural gas;– Coal;

• Burning these fossil fuels releases Carbon Dioxide (CO2) and Water (H2O) into the atmosphere.

• These add to the natural Greenhouse Gases which act as a blanket to trap the Earth’s heat;

• Global Warming is caused by too high a concentration of Greenhouse Gases which increases the world’s average temperature;

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Pollution from PlasticsPollution from Plastics• Fossil fuels are used to make plastics;Fossil fuels are used to make plastics;• Plastics decompose over 100s of years;Plastics decompose over 100s of years;• Burning fossil fuels releases their chemical Burning fossil fuels releases their chemical

energy in the form of thermal/heat energy energy in the form of thermal/heat energy as well as pollutants such as: as well as pollutants such as:

• GHG (GreenHouse Gases): GHG (GreenHouse Gases): Carbon Dioxide Carbon Dioxide (CO(CO22) and Water (H) and Water (H22O), Methane (CHO), Methane (CH44););• Smog: Smoke combined with FogSmog: Smoke combined with Fog

• Acid Rain: Water (HAcid Rain: Water (H220) combined with 0) combined with Nitrogen Oxides (NONitrogen Oxides (NOxx) and Sulphur Dioxide ) and Sulphur Dioxide (SO(SO22).).

Ozone LayerOzone Layer• Ozone (OOzone (O33

--)is one of the )is one of the gases that make up the air.gases that make up the air.• The ozone layer in the stratosphere The ozone layer in the stratosphere

primarily absorbs the sun’s ultra-violet primarily absorbs the sun’s ultra-violet rays. rays.

• Aerosol gases, like Chlorinated Aerosol gases, like Chlorinated FluoroCarbons (CFCs), reduce the ozone FluoroCarbons (CFCs), reduce the ozone layer allowing in more UV radiation.layer allowing in more UV radiation.

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Alternate Energy SourcesAlternate Energy Sources• AtmosphereAtmosphere

– Wind Energy – from energy of the wind;Wind Energy – from energy of the wind;• HydrosphereHydrosphere

– Tidal Energy – from motion of oceans due to Tidal Energy – from motion of oceans due to the moon’s and sun’s gravitational pull;the moon’s and sun’s gravitational pull;

– Hydro-Electric Energy – from falling water; Hydro-Electric Energy – from falling water; – Current Energy – from the ocean’s currents;Current Energy – from the ocean’s currents;

• LithosphereLithosphere– Geothermal Energy – from energy of the Earth;Geothermal Energy – from energy of the Earth;– Nuclear Energy – the energy stored in the Nuclear Energy – the energy stored in the

bonds inside the atom;bonds inside the atom;• Solar Energy – from energy of the Sun;Solar Energy – from energy of the Sun;

Tides

•A tide is the rise and fall of water in the seas

and the oceans caused by the gravitational force (pull) of the Moon, and to a lesser extent, the Sun.

•There are two high tides and two low tides daily.

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Hydrosphere• The Hydrosphere is the Earth’s outer The Hydrosphere is the Earth’s outer

layer of water:layer of water:– Liquid water – waterLiquid water – water– Solid water – ice– Gaseous water – water vapourGaseous water – water vapour

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CryosphereCryosphere• The Cryosphere consists of all the frozen The Cryosphere consists of all the frozen

water of the Earth’s surface;water of the Earth’s surface;• E.g. The Polar Ice Caps are floating masses of E.g. The Polar Ice Caps are floating masses of

ice at the North and South Poles;ice at the North and South Poles;• Melting of the Polar Ice Caps would release Melting of the Polar Ice Caps would release

water into the ocean, dilute the denser sea water into the ocean, dilute the denser sea water, and affect the Thermohaline water, and affect the Thermohaline Circulation;Circulation;

• The The Thermohaline Circulation is the is the movement of salty ocean water around the movement of salty ocean water around the world due to its density and temperature.world due to its density and temperature.

• The air masses that are over the oceans pick The air masses that are over the oceans pick up the heat, creating prevailing wind patternsup the heat, creating prevailing wind patterns..

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Glaciers• Glaciers are large land-based masses Glaciers are large land-based masses

of ice.of ice.• Global warming causes the glaciers to Global warming causes the glaciers to

melt and slide towards the oceans at melt and slide towards the oceans at an increasing rate.an increasing rate.

• This may cause the water levels of the This may cause the water levels of the oceans to rise.oceans to rise.

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Causes of Ocean PollutionCauses of Ocean Pollution• The Pacific Gyre is a place in the The Pacific Gyre is a place in the

Pacific Ocean where most of the Pacific Ocean where most of the water-borne plastics come together.water-borne plastics come together.

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WatershedWatershed• A watershed is an area of land in A watershed is an area of land in

which all inland waters drain into the which all inland waters drain into the same larger body of water;same larger body of water;

• E.g. In Quebec, we have three:E.g. In Quebec, we have three:– St. Lawrence River watershed;St. Lawrence River watershed;– Ungava Bay watershed; Ungava Bay watershed; – Hudson Bay watershed;Hudson Bay watershed;

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Watershed FactorsWatershed Factors• Factors that affect how water flows Factors that affect how water flows

within a watershed are:within a watershed are:– Topography – shape, slope, terrain of area;Topography – shape, slope, terrain of area;– Geology – type, depth, structure of the Geology – type, depth, structure of the

bedrock;bedrock;– Climate – rain or snowfall, winds and Climate – rain or snowfall, winds and

temperature;temperature;– Vegetation – density and diversity;Vegetation – density and diversity;– Land use – agricultural, industrial or urban;Land use – agricultural, industrial or urban;

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ProblemsProblems• Soil depletion – the loss of soil fertility;Soil depletion – the loss of soil fertility;• Soil erosion – soil being washed away;Soil erosion – soil being washed away;• Soil contamination - the abnormal Soil contamination - the abnormal

presence of harmful substances;presence of harmful substances;• Water depletion – loss of water because of Water depletion – loss of water because of

over-use reduces its availability for others;over-use reduces its availability for others;• Water contamination – contaminated Water contamination – contaminated

water will move downstream and affect water will move downstream and affect other areas.other areas.

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Causes of Freshwater Causes of Freshwater PollutionPollution• Industries release heated water Industries release heated water

– Thermal pollutionThermal pollution• Farming activities releaseFarming activities release

– Pesticides Pesticides – HerbicidesHerbicides– PhosphatesPhosphates– NitratesNitrates

• Bio-accumulation is the tendency among certain Bio-accumulation is the tendency among certain contaminants to accumulate over time in the tissues of living contaminants to accumulate over time in the tissues of living organisms.organisms.

• Toxins bio-accumulate more in higher trophic level organisms. Toxins bio-accumulate more in higher trophic level organisms.

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EutrophicationEutrophication• Eutrophication is the process by Eutrophication is the process by

which natural waters lose their which natural waters lose their oxygen because of an excessive oxygen because of an excessive accumulation of organic matter and accumulation of organic matter and nutrients;nutrients;

• E.g. fertilizer can harm organisms at E.g. fertilizer can harm organisms at different trophic levels in local food different trophic levels in local food chains or food webs.chains or food webs.

DisturbanceDisturbance• A disturbance is an event that damages A disturbance is an event that damages

an ecosystem.an ecosystem.• It can lead to the elimination of organisms It can lead to the elimination of organisms

and alter the availability of resources.and alter the availability of resources.• Disturbances are described by their:Disturbances are described by their:• Type: natural, human-causedType: natural, human-caused• Frequency: seasonal, freakFrequency: seasonal, freak• Seriousness: hailstorm, tornadoSeriousness: hailstorm, tornado

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Food RelationshipsFood RelationshipsSun Troph Vores Trophic LevelGrass Autotroph - Producer Cow Heterotroph Herbivore Primary ConsumerWolf Heterotroph Carnivore Secondary

ConsumerBear Heterotroph Omnivore Tertiary ConsumerVulture/Worm/Fungus Heterotroph Detritivor

eDecomposer

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Primary ProductivityPrimary Productivity• It is the amount of new bio-mass It is the amount of new bio-mass

generated by producers.generated by producers.• Primary productivity is a measure of Primary productivity is a measure of

what mass (kg) of plant growth can what mass (kg) of plant growth can occur in one year.occur in one year.

• E.g. crop or tree growthE.g. crop or tree growth• It depends on the availability of light, It depends on the availability of light,

heat, water and nutrients.heat, water and nutrients.

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Energy Flow in Trophic Energy Flow in Trophic SystemsSystems• Only 10% of the energy is Only 10% of the energy is

transferred between levels;transferred between levels;• Most is lost to motion, heat, waste.Most is lost to motion, heat, waste.

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Student Science Solution Student Science Solution BrainstormingBrainstormingProblemsProblems SolutionsSolutionsLand - Land - Land - Land - Air - Air - Air –Air –Water -Water -Water -Water -