biodiversity

• Climate Change


  Changes in global weather patterns, sea levels and temperatures
• Effects of Climate Change

  • Habitat loss
  • Animals forced to migrate
  • Some species and populations directly destroyed
  • Decreasing gene pool available for selection and evolution
  • Speed of climate change too fast for species to adapt to new conditions, leading to extinction
• Biodiversity


  The Variety of living organisms in an ecosystem
• Species richness


  The number of species in a habitat or community
• Levels of biodiversity


  • Habitat
  • Global
• Measuring species richness


  Counting the number of different species in the habitat
• Factors affecting biodiversity


  • Human population growth (using land to raise animals, urbanisation, hunting for food or fun)
  • Agriculture (monoculture)
  • Climate change
• Agriculture (monoculture)


  • Growing crops with the same requirements in terms of nutrition and ease of harvesting
  • Reduces biodiversity
  • Monocultures lacking genetic diversity may be less resistant to diseases
  • plus the use of fertilisers that could potentially leach into a river and kill aquatic life
  • Use of pesticides kills all nearby insects further reducing biodiversity
• Climate change


  • Habitat loss, driving animals to migrate
  • Some species and populations may be directly destroyed, decreasing the gene pool available for selection and evolution
  • The speed of climate change can sometimes be too fast for species to adapt to new conditions, leading to extinction
• What a keystone species and why are they important?


  Keystone species are species that have a significant impact on the ecosystem

  many species rely on the actions of the keystone species to survive as they may provide habitats which conditions for more and new species to survive
• What is genetic diversity?


  genetic diversity is the number and variation of alleles within a species
• Reasons to maintain biodiversity?


  Ecological reasons like the stability of the ecosystem (think about keystone species if they were to die the impact)

  Economical reasons like Ecotourism or the fact that many medicines are derived from plants and other organisms and some organisms may have health benefits we have yet to identify and extract

  Aesthetic reasons, humans like how nature looks

  Environmental reasons like climate change
• Species richness is the 


  total number of species in a habitat
• Species evenness is the 


  relative proportion of population size of species
• An ecosystem with higher biodiversity is more stable
• An advantage of greater genetic diversity is that the species is more likely to adapt to changes in the environment and survive against disease
• How does habitat loss due to human activity lead to less genetic diversity?

  
  

  Habitat loss occurs when an area of natural habitat is destroyed by human activity such as deforestation, agriculture, urbanisation etc. This can lead to extinction of native species and fragmentation of habitats which reduces gene flow between populations leading to reduced genetic diversity.
• Sampling methods that should be used: stratified and random
• How can pitfall traps be used?


  dig a hole and place a container

  Leave a cover to protect it from rain

  leave it overnight

  return and count the number of desired species caught

  do this multiple times in random location in each area you want to measure