The impact of environmental change

• Abiotic factors: influence the distribution of organisms

  • can be natural
  • can bee man - made (caused by humans)
• Natural : Geographic

  organisms vary in the tolerance of:

  • altitude
  • salinity
  • water availability

  Examples:

  • desert animals - kidneys conserve water
  • desert plants - no leaves to reduce water loss
  • aquatic plants - vary in tolerance of water (exposure to sun : exposure to water) (more sun = thick waxy cuticle)
• Natural

  Seasonal

  • temperature regions - temperature and water availability vary greatly
  • many species have to migrate to other regions in order to survive
  • less oxygen dissolves in water
• Impacts of no migration

  • Plants may not get pollinated
  • food webs may be distributed
  • diseases (like malaria) may become more wide spread
• Changes due to animal activities : tend to have a more extreme affect

  Burning fossil fuels

  • air pollution (carbon dioxide and Sulfur dioxide)

  Sulfer dioxide = acid rain

  Carbon dioxide = global warming, rise in sea levels

  Lichen - grows on bark wood etc, indicates a good air pollution

  • more lichen in the countryside - less pollution
• Changes due to animal activities

  Industrial and farming ( + sewage)

  Factories near water systems leak waste - causes water pollution

  • Mayfly nymphs - indicates clean / non-polluted water
  • Red midge - indicates polluted water - have a lot of hemoglobin
• Positive causes of these impacts

  • causes us to have a range of knowledge
  • allows us to put strategies in place to minimise these problems
• using invertebrates to indicate water pollution

  Positive : cheap, easy to do, not much equipment required

  Negative : not accurate, need to be able to identify species