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PollutionPollution

PHSciencePHScience

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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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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 E.g. Selenium metal is necessary in low dosages, but in high dosages it is toxic;in 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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Background• To understand how To understand how

the biosphere gets the biosphere gets polluted, we must polluted, we must study each of the study each of the “spheres” of the “spheres” of the biosphere (where all biosphere (where all life exists) and how life exists) and how they interact:they interact:– the atmosphere (air the atmosphere (air

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

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

(watery & icy regions);(watery & icy regions);– and the ecosphere and the ecosphere

(plants and animals). (plants and animals).

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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 or Ore are made of different Rocks or Ore are made of different proportions of minerals.proportions of minerals.

• There are many different types of granite There are many different types of granite rock depending on the relative rock depending on the relative concentrations of the minerals - feldspar concentrations of the minerals - feldspar (red), quartz (white) and mica (black)(red), quartz (white) and mica (black)

• A A mineral deposit is said to exist when the is said to exist when the amount and concentration of a mineral in amount and concentration of a mineral in the ore is high enough to be mined.the ore is high enough to be mined.

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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, metamorphic;Origin – sedimentary, igneous, metamorphic;

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Soil

• Soil is the mixture of Soil is the mixture of – Organic matter – decomposing Organic matter – decomposing

plants and animals;plants and animals;– Minerals;Minerals;– Broken-down rock material; Broken-down rock material;

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

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Life in the soil

• For soil to support life it must have:For soil to support life it must have:– A sufficient amount of dissolved A sufficient amount of dissolved

minerals;minerals;– Enough moisture;Enough moisture;– A good soil pH that is neither too acidic A good soil pH that is neither too acidic

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

acidity does not change too much;acidity does not change too much;

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Fossil Fuels and the Fossil Fuels and the AtmosphereAtmosphere

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

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

• Burning these fossil fuels releases Carbon Burning these fossil fuels releases Carbon Dioxide (CODioxide (CO22) into the atmosphere.) into the atmosphere.

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

• Global Warming is caused by too high a Global Warming is caused by too high a concentration of Greenhouse Gases which concentration of Greenhouse Gases which increases the world’s average temperature; 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 can take 100s of years to Plastics can take 100s of years to

decompose;decompose;• Burning fossil fuels releases their chemical Burning fossil fuels releases their chemical

energy in the form of thermal energy or energy in the form of thermal energy or heat for use in car engines;heat for use in car engines;

• One of the products of burning fossil fuels One of the products of burning fossil fuels is Carbon Dioxide (COis Carbon Dioxide (CO2 2 ););

• This also increases the greenhouse gas This also increases the greenhouse gas effect and warms the Earth up;effect and warms the Earth up;

• Other products are Nitrogen Oxides (NOOther products are Nitrogen Oxides (NOxx) ) and Sulphur Dioxide (SOand Sulphur Dioxide (SO22) which form ) which form Acid Acid RainRain;;

Ozone LayerOzone Layer

• Ozone (OOzone (O--33)is one of the gases that )is one of the gases that

make up the air.make up the air.

• The ozone layer in the stratosphere The ozone layer in the stratosphere primarily absorbs the sun’s ultra-primarily absorbs the sun’s ultra-violet rays. violet rays.

• Aerosols gases like Chlorinated Aerosols gases like Chlorinated FluoroCarbons (CFCs) reduce the FluoroCarbons (CFCs) reduce the ozone layers allowing more CFCs in.ozone layers allowing more CFCs in.

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ActivityActivity

• Soil Analysis Demo Soil Analysis Demo

• Page 214, Q. 1-9Page 214, Q. 1-9

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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 Geothermal Energy – from energy of the

Earth;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.up the heat.

• This helps create prevailing wind patternsThis helps create 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.melt and slide towards the oceans.

• 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 The Pacific Gyre is a place in the 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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ActivityActivity

• Rock collection;Rock collection;

• Workbook, page 97 & 99, 101 & 102;Workbook, page 97 & 99, 101 & 102;

• Textbook page 215, Q. 20-23Textbook page 215, Q. 20-23

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Watershed

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

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EutrophicationEutrophication

• Eutrophication is the process by which Eutrophication is the process by which natural waters lose their oxygen natural waters lose their oxygen because of an excessive accumulation because of an excessive accumulation of organic matter and nutrients;of organic matter and nutrients;

• E.g. fertilizerE.g. fertilizer

• This harms organisms at different This harms organisms at different trophic levels in local food chains or trophic levels in local food chains or food webs.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 Level

Grass Autotroph - Producer

Cow Heterotroph Herbivore Primary Consumer

Wolf Heterotroph Carnivore Secondary Consumer

Bear Heterotroph Omnivore Tertiary Consumer

Vulture/Worm/Fungus Heterotroph Detritivore

Decomposer

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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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ActivityActivity

• Textbook page 216, Q. 33-36, A,B,D;Textbook page 216, Q. 33-36, A,B,D;

• Misconceptions on Global Climate Misconceptions on Global Climate ChangeChange

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Student Science Solution Student Science Solution BrainstormingBrainstormingProblemsProblems SolutionsSolutions

Land - Land -

Land - Land -

Air - Air -

Air –Air –

Water -Water -

Water -Water -