Environmental Risks -

• Soil Erosion:

  • Occurs in farms, where rainforest is cleared – soil is washed away by rain because there are no tree roots to retain it
  • In the Amazon rainforest, eroded soil goes into rivers & pollutes drinking water

• Global Warming:

  • Occurs due to too much greenhouse gases

• Greenhouse Effect:

  • When infrared radiation passes through the atmosphere, & some is absorbed and re-emitted in all directions by greenhouse gas molecules
  • This warms the surface & lower atmosphere

• Effects:

  • Melting poles = rising sea levels = increase in storms
  • Change in the distribution of precipitation
  • Plants and wildlife might not have time to adjust
  • Lower crop yields in Africa, Asia & Latin America
  • More people at risk from insect/water-borne diseases

• Greenhouse gases are:

  • CO2 from burning fossil fuels or wood
  • Methane from decomposing organic matter & waste
  • CFCs from aerosols, air conditioners, & refrigerators
  • Nitrogen Oxides from car exhausts & power stations

• Air pollution:

  • Carbon monoxide: incomplete combustion of carbon-containing substances causes oxygen starvation
  • Sulphur dioxide: combustion of fossil fuels causes respiratory problems and acid rain
  • Nitrogen oxides: N & O from air combine due to heat (furnace/engine); same effect as sulphur dioxide
  • Lead oxide: burning leaded petrol damages nervous system

• Water Pollution:

  • Chemicals in fertilizers cause eutrophication
  • Oil spilling into the sea
  • Acid rain destroys lakes and kills animals/plants
  • Health hazards for humans
  • Damages limestone buildings and sculptures
  • Fewer crops can be grown on an acidic field

• Noise Pollution:

  • Vehicles
  • Machinery in industries and farms
  • Noisy humans

• Visual Pollution:

  • All man-made things are ugly compared to unspoiled nature

• Desertification:

  • Overgrazing
  • Soil erosion
  • Global climate getting warmer - gets drier due to less rain
  • Deforestation - fewer roots of trees to hold the soil together

• Sustainable Development: Economic development without destroying natural resources

• Management:

  • Population policies
  • Sustainable tourism
  • Use of renewable energy
  • Afforestation

• Resource Conservation: Meeting needs of the present without affecting needs for the future

• Ways of Conservation:

  • 3 Rs: reduce, reuse, recycle
  • Renewable energy
  • Use energy-efficient products
  • Restrict the use of resource
  • Use more public transport
  • The government can raise tax on petrol prices

  

  

  

  soil erosion causes