3.Biodiversity

• Biodiversity meaning


  • Variety of all the different species of organisms on earth, or within an ecosystem
• What does a great biodiversity ensure?

  • stability of ecosystems by reducing the dependence of one species on another for food, shelter and the maintenance of the physical environment
• What does the future of human species on Earth rely on?

  • maintaining a good level of biodiversity
• Consequence of human activity

  • reduction in biodiversity
• Consequence of rapid growth of human population

  • increasingly more resources are used
  • more waste is produced
• Consequence of increase in standard of living

  • increasingly more resources used
  • more waste is produced
• 3 types of pollution

  • Water pollution
  • Air pollution
  • land pollution
• Water pollution 


  • From sewage, fertiliser or toxic chemicals
• Air pollution 


  • From smoke and acidic gases
• Land pollution 


  • Landfill and from toxic chemicals
• Effect of pollution on plants and animals

  • Kills them
  • Reducing biodiversity
• 2 examples of water pollution

  Fertiliser run off

  • algae multiply
  • algae block light so plants cannot photosynthesise
  • lack of oxygen for respiration - fish die

  particles

  • block light
  • plants cannot photosynthesise
  • less glucose made
• 2 examples of air pollution

  Greenhouse gases : carbon dioxide

  • global warming
  • more extreme weather
  • ice caps melt - sea levels rises - flooding

  Carbon monoxide

  • combines with haemoglobin
  • less oxygen carried by haemoglobin
• Examples of land use

  Providing land :

  • quarrying
  • building
  • farming / agriculture
  • dumping waste
• Use of peat bogs

  • Composts
  • Fuels
• Two reasons why farmers should use less peat

  • Reduces biodiversity
  • Peat being used faster than it forms
• Decay or burning of peat leads to:

  • Releases carbon dioxide into the atmosphere
  • Leading to global warming
• Consequence of destroying peat bogs

  • The destruction of peat bogs, and other areas of peat to produce garden compost, reduces the area of this habitat.
  • Reduces biodiversity
• Deforestation


  Large scale:

  • provide land for cattle and rice fields
  • grow crops for biofuels
  • provide land for buildings
  • provide land for farming
• Increase in rice fields

  • Increase the amount of methane released into the atmosphere
• Describe three ways in which large-scale deforestation in tropical areas has increased the concentration of carbon dioxide in the atmosphere.

  1. loss of habitat / shelter
  2. fewer plant species due to clearing
  3. loss of food source
• What are the negative effects of deforestation?


  • Animals and birds migrate due to less food
  • More habitats are destroyed
• Give two possible effects of a rise in the Earth’s temperature.

  1. reduce biodiversity
  2. change in migrations patterns
• Environmental implications of deforestation

  • trees burnt releases carbon dioxide into the atmosphere
  • less trees to remove carbon dioxide from atmosphere during photosynthesis
  • loss of habitat which may lead to possible extinction
  • loss of habitat lead to migrations
  • soil erosion due to shallow roots
• Two effects of global warming

  CLIMATE CHANGE :

  • warmer climate
  • food production affected
  • major ecosystems destroyed

  SEA LEVEL RISE:

  • low-lying land flooded, especially coastal areas
  • less food grown
  • homes flooded

  DESTRUCTION of habitats / extinction / reduction in biodiversity
• What have scientists and concerned citizens put in place to maintain biodiversity?

  • Programmes to reduce the negative effects of humans on ecosystems and biodiversity
• Programmes include :


  • Breeding programmes for endangered species
  • Protection and regeneration of rare habitats
  • Reducing deforestation by some governments
  • Reducing carbon emissions by some governments
  • Recycling resources rather than dumping waste in landfill
  • Reintroduction of field margins and hedgerows in agricultural areas where farmers grow only one type of cro