Disrupting Ecosystems

• What is biodiversity?

  The variety of species on Earth
• How does high biodiversity affect ecosystems?

  It helps ecosystems become stable
• Why is the future of humans linked to biodiversity?

  Humans rely on biodiversity for survival
• What human activities reduce biodiversity?

  Pollution, deforestation, and urbanization
• What actions are being taken regarding biodiversity reduction?

  Efforts are being made to stop it
• What factors put biodiversity at risk?

  • Changes in availability of water
  • Changes in temperature
  • Changes in atmospheric gases
• What can cause changes in biodiversity factors?

  Seasons, geographic activity, and human actions
• What is one consequence of pollution on biodiversity?

  Pollution kills plants and animals
• How does the increase in human population affect resource use?

  It leads to more resources being used
• What is a result of the increase in the standard of living?

  More waste is produced
• What happens if waste and chemical materials are not properly handled?

  More pollution will be caused
• What are the three main types of pollution mentioned?

  • Water pollution
  • Air pollution
  • Land pollution
• What are common sources of water pollution?

  Sewage, fertilizers, and toxic chemicals
• What gas contributes to air pollution and acid rain?

  Sulfur dioxide
• How does sulfur dioxide contribute to acid rain?

  It dissolves in moisture in the atmosphere
• What causes land pollution?

  Landfill and toxic chemicals
• How can pesticides and herbicides affect water sources?

  They may be washed from land into water
• What can put biodiversity at risk according to humans?

  Taking too many resources from the environment
• How do human activities reduce land available for wildlife?

  Through building, quarrying, farming, and waste dumping
• What is the impact of producing garden compost on peat bogs?

  It destroys peat bogs and their habitats
• What greenhouse gas is released by the decay or burning of peat?

  Carbon dioxide
• What is the term for cutting down trees and destroying forests?

  Deforestation
• Why has deforestation occurred in tropical areas?

  To provide land for cattle and rice fields
• What is one reason for growing crops in deforestation areas?

  To produce biofuels
• What is global warming?

  A gradual increase in Earth's temperature
• What do scientists agree is causing global warming?

  Changes in gases from human activities
• What is the basis of the scientific consensus on global warming?

  Systematic reviews of peer-reviewed publications
• Key Point

  Many garden centres now sell 'peat-free' compost to try and reduce the destruction of peat bogs.
• Which gases are primarily involved in global warming?

  Carbon dioxide and methane
• What are the biological consequences of global warming?

  • Loss of habitats due to flooding
  • Changes in species distribution
  • Altered migration patterns of animals
• Key Point

  Any increase in carbon dioxide levels will cause photosynthesis rates to increase. However, there is a limit to how well plants will be able to reduce the effect of global warming, especially if huge areas of rainforests are cut down.
• Conserving Biodiversity


  . Scientists and some governments have taken steps to reduce pollution and over-exploitation to help maintain biodiversity. These include:

  - setting up breeding programmes in zoos for endangered species

  - protecting rare habitats, e.g. coral reefs, mangroves and heathland

  - encouraging farmers to reintroduce margins and hedgerows in fields where only one type of crop is grown

  - reducing deforestation carbon dioxide emissions

  - recycling resources rather than dumping waste in landfill