Pollution (Cambridge International IGCSE Geography)

Spec point — 3.7.3 · Describe how economic activities may pose threats to the natural environment & people, locally & globally

Pollution

• Pollution is the introduction of harmful contamination into the environment

• As development has occurred in countries around the globe, levels of pollution have increased

• There are five main types of pollution:

  • Air
  • Water
  • Land
  • Visual
  • Noise

Air pollution causes and impacts

• Air pollution is a combination of indoor and outdoor particulates

• Sources of air pollution include:

  • motor vehicles powered by petrol/diesel
  • factories
  • power stations burning fossil fuels
  • forest fires
  • open fires and wood-burning stoves

• There are many impacts of air pollution, including:

  • It contributes to 12% of annual deaths worldwide

    • This is highest in middle- and low-income countries

  • Indoor pollution in LEDCs due to the use of fuelwood for cooking and heating increases health impacts

  • Increased release of greenhouse gases contributes to the enhanced greenhouse effect

Water pollution causes and impacts

• Water pollution occurs when harmful substances contaminate streams, rivers, aquifers, and oceans

• The sources of water pollution include:

  • fuel spillages
  • agricultural waste/pesticides/fertilisers
  • leaching of toxic materials from waste
  • sewage disposal into rivers and seas
  • boat oil/diesel waste
  • deforestation leads to soil erosion and soil being washed into waterways
  • plastic waste—becoming microplastics
  • radioactive waste

• The impacts of water pollution are widespread and include:

  • Reduction in available clean drinking water
  • Reduction in crop yields and death of crops
  • Damage to ecosystems and habitats
  • Death of wildlife
  • Abnormalities in fish and other sea/water wildlife
  • Accumulation of toxins in the food chain
  • Spread of diseases such as cholera and typhoid

Land pollution causes and impacts

• Land pollution is the presence of contaminants in the soil at high enough concentrations to pose a risk to humans and the environment

• Sources of land pollution include:

  • solid waste—from domestic and industrial sources
  • agricultural waste/pesticides/fertilisers
  • mining waste - toxic heavy metals such as mercury
  • demolition and construction waste

• The presence of land pollution can lead to:

  • reduced crop yields
  • leaching of toxins into the water system
  • pollutants entering the food chain through plants
  • ecosystem and habitat destruction
  • economic losses

Visual pollution causes and impacts

• Visual pollution is the impact of human-made constructions or pollution that affect the visual landscape

• The main causes of visual pollution include:

  • buildings
  • energy production - power stations, wind turbines
  • signs and advertising (billboards with lights)
  • power lines and structures (pylons, mobile phone masts)
  • waste

• The impacts of visual pollution include:

  • a lower quality of life
  • stress and anxiety
  • an impact on the economy
  • distraction - may lead to accidents

Noise pollution causes and impacts

• Noise pollution is defined as harmful or annoying levels of noise in an environment

• The causes of noise pollution include:

  • transport - roads and airports
  • construction
  • industry
  • night activities—nightclubs, bars
  • energy production - wind turbines, power stations

• Noise pollution has a range of impacts, including:

  • hearing loss
  • scaring wildlife—affects feeding and breeding
  • sleep disturbance
  • stress and anxiety
  • contributing to high blood pressure, heart disease
  • negative effects on child development

Worked Example Study Fig 1, which shows information about threats to the natural environment in the Caspian Sea.

Using evidence from Fig 1 only, suggest three likely impacts on the natural environment of pollution in the Caspian Sea.

[3 marks]

• Answer:

  • Damage to wetlands/river delta [1]
  • Kills species in wetlands/river deltas/impacts food chains in wetlands/river deltas [1]
  • Fish killed/numbers decrease/abnormalities [1]
  • Fish unable to spawn/spawning/breed/breeding grounds destroyed [1]
  • Habitats destroyed [1]

Sustainable management of pollution

• Sustainable management of pollution means ensuring that industries, urban growth, agriculture and domestic activities impact the soils, air, water, landscape and noise levels as little as possible
• There are many ways in which this can be achieved

Air

• Improved public transport and electric vehicles to reduce transport emissions
• Increase the use of renewable energy
• Congestion charges in large cities such as London to reduce the use of vehicles
• Use of unleaded and low-sulphur fuels
• Filters on the chimneys of factories and power stations
• Smokeless fuels
• International agreements (Paris and Kyoto) regarding gas emissions
• Reduced use of energy to reduce the need for fossil fuel power stations

Water

• Regulations on the amounts of fertilisers and pesticides used
• Increased use of water treatment works to treat sewage waste before releasing it back into the waterways
• Education regarding the disposal of plastic waste
• Fines for factories/industries discharging waste into waterways

Land

• Recycling and reuse of materials to reduce the amount of waste
• Separation of waste into compostable and recyclable waste by householders
• Regulations regarding the use of fertilisers and pesticides
• Targets set for local councils and authorities regarding recycling

Visual

• Reduction in the number of billboards/advertising boards that can be in an area
• Planting of trees to screen roads/quarries and other developments
• Buildings that blend into the environment
• Disguising mobile phone masts
• Putting electrical and telephone cables underground
• Regular waste collection and provision of bins

Noise

• Limiting hours of work for construction sites and factories
• Noise barriers between houses and main roads
• Siting activities away from population centres