Pollution

Pollution: The introduction/disposal of harmful substances/waste into the environment

Visual pollution: pollution that spoils the beauty of the landscape/ pollution that is visible to the eye.

Atmospheric pollution: When the air is made unclean/ contaminated by chemicals.

Water pollution: When the water bodies are made unclean/ contaminated by chemicals.

Noise pollution: disturbing/excess noise that harm activity/balance of human/animal life.

Light pollution: Excessive/obtrusive artificial light

 

Ways in which agriculture can cause atmospheric pollution 

• chemical sprays/fertiliser sprays/insecticide sprays

• smells from manure/silage

• methane from cattle/gas from cows

• fumes from agricultural machinery or tractors/tractors burn fossil fuels

• burning stubble/burning vegetation for farmland 

 

Impact of high level of air pollution on natural environment

• Loss of/damage to natural vegetation

• Habitat loss

• Impact on ecosystems/food chains

• Birds/insects/animals killed/poisoned

• Extinction of species

• Acid rain pollutes water

• Acid rain decreases soil pH

 

How the following economic activities pollute water

• Manufacturing: disposal of toxic waste by manufacturing industry; dirty/waste water

• Transport: oil spills from tanker accidents/washing out fuel tanks/fuel spills

• Power Stations: return of hot water to rivers from power stations/radioactive water to sea from nuclear power stations

• Agriculture: runoff of fertilisers/pesticides from farmland/animal waste or slurry 

 

How local environment is affected by water pollution

• Nutrients from fertilisers change composition of water

• Growth of algae

• Lowering of oxygen supply

• Eutrophication 

• Kills fish

• Predators have no food

• Destruction of food chain/ecosystem 

 

How pollution of beaches can affect the natural environment

• damages habitats

• impacts on food chains

• disrupts breeding patterns

• kills animals/fish/birds/ species

• extinction/endangered

• loss of biodiversity

 

Sources of outdoor/environmental noise pollution

• Traffic/transport/cars/bikes

• Air traffic/aircrafts 

• Machines used in factories 

• Construction sites

• Nightlife/parties 

 

Impacts of noise pollution

• Physical: Headaches, High pulse rate, High blood pressure, Heart attacks/strokes

• Psychological: stress, fatigue, depression, anxiety in humans and animals

• Behavioural disorders: aggressive behaviour & irritability

• Loss of sleep

• Memory & concentration: affect ability to focus, and affects memory

 

Sources of light pollution

• Interior & exterior lighting of buildings

• Advertising

• Street lighting

 

Impacts of light pollution: headache, fatigue, loss of sleep

 

Global warming 

Greenhouse gases

examples of greenhouse gases: carbon dioxide, methane, nitrous oxides, chlorofluorocarbons (CFCs)

 

How greenhouse gases build up in the atmosphere

• Burning of fossil fuels, e.g. oil/coal

• Cars/engines

• Aircraft emissions

• Thermal/coal/oil/gas power stations/electricity generation

• Industry/manufacturing/industrialization

• Deforestation/forest fires: Reduces capacity of vegetation to convert carbon dioxide to oxygen/absorb carbon dioxide/gases

• Methane from rice fields/grazing livestock

 

How increase in greenhouse gases causes global warming

• Greenhouse gases form a layer/blanket

• Sun’s rays pass through the atmosphere

• Short wave energy comes in

• Rays/heat bounce off/radiate from the surface of the earth

• Rays/heat trapped/can’t escape

• Long wave/infrared energy doesn’t leave

• Temperatures increase/heat builds up

• Greenhouse gases increase/build up

 

Human activities that worsen global warming

• burning fossil fuels/oil/coal

• generating electricity/power stations/using electronic devices/using air conditioning

• transport/cars/vehicles/trains/lorries

• aviation/planes

• shipping

• factories

• deforestation

• rice production

• cattle grazing

• landfill sites

 

Why global warming is a threat to natural environment 

• melting of ice caps/glaciers

• flooding of low lying islands/countries // rising sea/water levels

• some areas will become drier/desertification occurs/more droughts

• loss of natural habitat

• impact on food chains; loss of food sources for wildlife

• loss of species/extinction/animals die 

• warming of sea water can destroy/bleach coral

• diversion of cold ocean currents

• loss of biodiversity; vegetation/trees die

• forest fires

 

How melting of ice (by global warming) causes problems for people & natural environment

• Flooding of coastal lowlands/areas/islands/cities

• Loss of cultivable land/farmland/settlement/people are displaced

• Soils become swampy/saline

• Less freshwater supply from glaciers/in mountainous areas

• Increasing cost of coastal protection

• Loss of income from tourism on glaciers/in mountainous areas

• Impacts on food chains/destruction of ecosystems

• Habitat loss

• Threat to wildlife/extinction of species/reduced biodiversity/animals die

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Desertification  

The process by which fertile land becomes less productive; makes the surface unsuitable for vegetation to grow/land becomes desert/dry/arid. 

 

How climate change causes desertification 

• Less rain falls/drought/rapid evaporation

• Plants do not grow/die/soil becomes bare

 

How population growth causes desertification 

• More food is needed

• Areas are overgrazed/over cultivated

• People need more fuel/homes/settlements

• Trees are cut down/soil/land becomes bare

 

How economic activity leads to increased risk of desertification

• Cultivation in marginal areas

• Overcultivation

• Less humus to bind the soil

• Deforestation/excessive fuel wood collection

• Leaves areas unprotected/subject to soil erosion/removal by wind

• Removes protective vegetation cover from the soil/less roots to bind soil

• Overgrazing/trampling of cattle

• Causes deterioration of pasture

• Removal/extraction of water from underground/for industry/for agriculture leads to death of vegetation

• Use of manure as fuel

 

Impacts of desertification

• Loss of soil nutrients

• Loss of biodiversity/vegetation

• Reduction in available land for cultivation/grazing

• Soil erosion

• Loss of income from agriculture/pastoral

• Increased poverty

• Lack of food supply

• Lack of firewood for fuel

• Forced migration

 

Methods people in rural areas of LEDCs can use to reduce desertification

• Limit size of herds/rotate grazing land: So, less overgrazing

• Plant trees/shelter belts/afforestation: Roots bind soil // less deforestation // less surface runoff

• Education about agricultural techniques

• Contour ploughing/ploughing across slope: less soil erosion // less surface runoff

• Crop rotation: less soil erosion // less surface runoff // improve soil fertility 

• Terracing: less soil erosion // less surface runoff

• Maintain soil cover/plant drought resistant plants

• Mulching: less soil erosion // less surface runoff // improve soil fertility 

• Micro HEP project/small scale cookers

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Other environmental risks

Acid deposition 

Causes of acid deposition

• Acid rain

• Rotting vegetation

• Erupting volcanoes

• Burning of fossil fuels (SO2 & oxides of nitrogen)

• Power plants (SO2)

 

Impacts of acid deposition

• Damages forests (trees & needles)

• Makes it harder for trees to take up water

• Depletes soil of essential nutrients

• Reduces crop yields

• Increases acidity of lakes/rivers; toxic to aquatic life

• Reduces visibility 

• Corrodes building materials/historic buildings

 

Soil erosion 

How agriculture may cause soil erosion

• deforestation/clearance of vegetation

• monoculture/overcultivation

• ploughing up and down the slope

• leaving areas of land fallow

• Overgrazing

 

Ways in which economic activities & natural processes cause soil erosion

• Deforestation

• removes vegetation cover

• ploughing leaves soil bare

• soil dried out in arid conditions/drought

• so it can be blown away by wind

• heavy rainfall/storms/floods washes soil away

• overcultivation

• removes nutrients from soil

• and destroys structure of soil

• grazing by animals

• especially if herds are too large

 

Impacts of soil erosion

• Loss of land/farmland/grazing land

• Loss of vegetation/trees

• Soil is made bare

• Gulleys/cliffs/steep slopes created in soil

• Soil washed away 

 

How manufacturing industry/ factory may threaten local natural environment

• Air pollution/smoke/gas emissions/ greenhouse gases

• Water/river pollution; acid rain pollutes water

• Loss of habitats 

• Impact on ecosystems/food chains

• Noise scares wildlife

• Kills wildlife/birds/insects/animals

• Extinction of species

• Loss of/damage to natural vegetation/deforestation;

• Industrial waste 

 

Why manufacturing industry leads to loss of biodiversity

• loss of habitat

• destruction of food chains

• wildlife poisoned/killed by fumes

• wildlife poisoned/killed by pollution of water courses

• forest/vegetation cut down/deforestation

 

How local natural environment may be at risk from industries such as fish processing

• Loss of habitat

• Animals scared by noise

• Water pollution

• Reduction of fish stocks

• Disruption to food chains

• Lowering of water table

• Deforestation

• Air pollution

 

Conservation

Managing use of natural resources to benefit current generations & maintain capacity to meet needs of future generations. 

 

Importance of conserving natural resources & natural environment

• many resources are non–renewable/will run out/are finite

• life in future would not be possible without clean water

• life in future would not be possible without clean air

• life in future would not be possible without land for cultivation

• to protect habitats

• conserving natural environment will ensure ecosystems remain in balance

• forests act as carbon sinks 

• species do not become extinct/animals do not die

• to prevent global warming, acid rain, desertification 

• creates conflict/civil rest

 

Conservation methods

• Reduce the use of fossil fuels

• Energy-efficient methods & policies 

• Reduce the amount of waste produced

• Recycle

• Reuse

• Substitution: use of common/less valuable resources instead of rare/ expensive ones.

• Quotas: agreement between countries to take predetermined amount of a resource

• Rationing: restricting the amount of resource available per week, day, etc.

• Product stewardship: manufacturers, retailers & consumers are encouraged to take responsibility to reduce the impact of a product on the environment.  

 

Energy conservation methods

Government 

• Investment in renewable energy

• Improve public transport

• Set taxes on petrol/fuel

• Set limits for fuel consumption for cars/buses, etc.

• Offer grants/subsidies to households to improve energy efficiency

• Set laws/limits for industries. Eg. carbon credits: industries have to buy permits to emit greenhouse gases over the limit they are allowed. 

 

Individuals 

• Walk/cycle for short journeys

• Multi-purpose trips to reduce use of vehicles

• Use public transport

• Carpool

• Buy low emission cars

• Use low-energy lightbulbs

• Use high-efficiency appliances

• Turn off lights/appliances when not in use

• Improve insulation

• Wash clothes at low temperatures