Chapter 18

• Biodiversity


  All of the different species living in a certain ecosystem
• Importance of biodiversity


  • Biodiverse environment is usually a stable environment
  • Species can rely on other species to survive
• Biodiversity is being threatened due to the human population explosion
• Human population explosion


  Humans are taking over the planet and their numbers are growing massively
• Reasons for rapid human population growth

  • Less people dying of illnesses
  • Better healthcare
  • Spread of information
  • Healthier lifestyles
  • No natural predators
• There are now 7 billion humans on planet earth
• Pressures on the world due to human population growth

  • Draining of natural resources
  • Less space for animals
  • Increased pollution
• Land pollution


  Plastic waste that is non-biodegradable
• Water pollution


  Fertilizers washed into river ecosystems causing plant and fish death
• Bio-indicator


  Used to look at how we are affecting river ecosystems, e.g. shrimp numbers decreasing indicates pollution
• Bioaccumulation


  Chemicals travelling through the ecosystem and becoming more toxic, affecting top predators
• Example of bioaccumulation is mercury in sharks
• Sewage and drugs flushed into rivers contribute to water pollution
• Air pollution


  Burning of fossil fuels releases carbon dioxide and contributes to greenhouse effect and global warming
• Fossil fuels


  • Coal
  • Oil
  • Natural gas
• Sulfur dioxide from burning fossil fuels creates acid rain
• Deforestation


  • Cutting down of trees for buildings, farming and housing
  • Loss of carbon sinks
  • Loss of specific wildlife habitats
• Peat bogs


  • Plant matter that hasn't fully decayed, acting as carbon stores
  • Being removed for use as fertilizers
• Efforts to combat environmental issues


  • Breeding programs for endangered species
  • Reforestation
  • Recycling waste
  • Reducing carbon emissions
• Food consumption and production


  • Meat production is bad for the environment due to methane emissions and energy loss through the food chain
  • Vegetarian/vegan diets are more sustainable
• Food security


  • Ability to meet the food needs of the population
  • Affected by human population growth, disease, changing diets, and economic factors
• Sustainable farming


  • Meeting the needs of today without hindering future generations
  • Examples include greenhouse farming and fish farming