MODULE 8

• Biodiversity

  Variety and extent of differences among and within living things
• of biodiversity

  • Genetic diversity
  • Species diversity
  • Ecosystem diversity
• Examples of genetic biodiversity

  • Color of corn
  • Fur color and sizes of cats and dogs
  • Skin color
  • Eye color
  • Fur color
• Species richness

  Number of different kinds of organisms present in a particular area
• Species evenness

  Compares the similarity of the population size of each of the species present
• Biodiversity attributes

  • Compositional biodiversity
  • Structural biodiversity
  • Functional biodiversity
• Compositional biodiversity

  Variety of components present at each level (genes, species, ecosystems)
• Structural biodiversity

  Variety of ways in which components (genes species, ecosystems) are arranged over space and time
• Functional biodiversity

  Variety of biological processes due to species interaction that generate biodiversity
• Surrogate species

  • Keystone species
  • Umbrella species
  • Indicator species
  • Flagship species
• Keystone species

  Impact on the community or ecosystem are much larger relative to its abundance, and more influential than expected
• Example of keystone species

  • Tigers
• Umbrella species


  One with large habitat area and exerts a major ecological influence on the community
• Example of umbrella species

  • Philippine eagle
• Indicator species


  Species that are sensitive to certain environmental factor changes thus only found in environments where these factors are optimal
• Examples of indicator species


  • Lichens and freshwater invertebrates
• Flagship species


  Popular, charismatic species that serve as symbols and rallying points to stimulate conservation awareness and action
• Examples of flagship species


  • Tarsier, polar bears, deers, eagle, tamaraw
• Biodiversity hotspot


  Place on Earth that is both rich in endemic species living in a deeply threatened habitat mainly due to human activity
• Criteria for biodiversity hotspot


  • Have a high percentage of endemic plant life of at least 1,500 endemic vascular plants
  • Have 30% or less of its original natural vegetation
• Biodiversity coldspot


  Places on earth not rich in endemic species, but have high biodiversity and ecosystem service values but low threat values
• Conservation strategies


  • Reactive
  • Proactive
• IUCN categories


  • Extinct (EX)
  • Extinct in the wild (EW)
  • Critically endangered (CR)
  • Endangered (EN)
  • Vulnerable (VU)
  • Near threatened (NT)
  • Least concern (LC)
  • Data deficient (DD)
  • Not evaluated (NE)
• Extinct (EX)


  When there is no doubt that the last individual has died
• Extinct in the wild (EW)


  When it is knows only to survive in cultivation, in captivity
• Critically endangered (CR)


  The calculated probability of extinction during the next 10 years of >50%
• Example of critically endangered species


  • Chinese stripe-necked turtle
• Endangered (EN)


  Calculated probability of extinction during the next 20 years is >20%
• Example of endangered species

  • Tiger
• Vulnerable (VU)


  Calculated probability of extinction during the next 20 years is at least 10%
• Near threatened (NT)


  Does not qualify for Critically Endangered, Endangered or Vulnerable now, but is close to qualifying for or is likely to qualify for a threatened category in the near future
• Example of near threatened species


  • Western white pine
• Least concern (LC)


  Widespread and abundant taxa are included in this category
• Example of least concern species


  • Black emo skink
• Data deficient (DD)


  There is inadequate information to make a direct, or indirect assessment of its risk of extinction
• Not evaluated (NE)


  No assessment has been made
• Causes of biodiversity loss


  • Population growth or overpopulation
  • Habitat loss (deforestation, loss of mangrove species, invasive alien species, urbanization, environmental pollution)
  • Climate change
• Effects of Biodiversity Loss


  • Threats to food security
  • Threats to energy security
  • Unavailability of clean water
  • Damage to social relationships
• Levels of biodiversity


  • Genetic
  • Species
  • Ecosystem
• biodiversity attributes

  • Composition
  • Structure
  • Function