Biodiversity

• Define Biodiversity:

  The variation of living organisms in an ecosystem
• Define Habitat:

  The place where individuals of a species live
• State two ways biodiversity can be measured:

  • Species richness
  • Species evenness
• Define Species Richness:

  The number of different species in a community
• Define Species Evenness:

  The number of individuals of each species living together in a community
• Define Species:

  A group of organisms that can successfully produce fertile offspring
• The more variation of genes present, the more likely a species is to be able to adapt to changes in the environment
• Name population estimate techniques:

  • Quadrats
  • Point quadrats
  • Line transect
  • Belt transect
• Define Variation:

  The differences between individuals due to genes and/or the environment
• State four types of sampling strategies:

  • random
  • non-random opportunistic
  • non-random stratified
  • non-random systematic
• State the advantage of random sampling:

  • not bias
  • easier
  • quicker
• State the advantage of non-random opportunistic sampling:

  • easier
  • quicker
• State the advantage of non-random stratified sampling:

  • ensures that all different areas of a habitat are sampled- decreases under representation
  • accurately reflects population structure, guaranteeing proportional representation of all individuals, allows analysis of specific areas and observe relationships between individuals of different areas
• State the advantage of non-random systematic sampling:

  • useful to show a clear gradient in environmental factors
  • easy
  • quick to use
  • suitable for larger samples and populations
• State the disadvantage of random sampling:

  • may not equally cover all areas of the habitat
  • species of low presence may be missed resulting in an underestimate of biodiversity
• State the disadvantage of non-random opportunistic sampling:

  • bias - resulting in an over estimate of biodiversity, under representing individuals, highly dependant on researcher
• State the disadvantage of non-random stratified sampling:

  • the habitat must be clearly classified into areas
  • same disadvantages as random sampling in each area: may not equally cover all areas of habitat, species of low presence may be missed resulting in an underestimate of biodiversity
• State the disadvantage of non-random systematic sampling:

  • only the species on or within the belt can be recorded - resulting in an underestimate of biodiversity
• Define a Quadrat:

  A square frame used to define the size of the sample area
• Define a Transect:

  A line taken across the habitat
• Name two non-random systematic sampling techniques:

  • line transect
  • belt transect
• Define Genetic Diversity:

  The variation (variety of genes) amongst individuals of the same species
• Define Sample:

  A small proportion of the population
• Define Climax Community:

  When a community is stable and the final stage of succession
• Define Habitat Diversity:

  The range of different habitats
• What is the name of the formula used to calculate biodiversity?

  Simpson's Index of Diversity
• What does n represent in the Simpson's index of Diversity?

  the number of individuals of a species or the percentage cover

  
• What does N represent in the Simpson's Index of Diversity?

  the total number of individuals of all species or total percentage cover

  
• For calculating biodiversity with the Simpson's Index of Diversity:

  • a high value of D indicates a diverse habitat

  ∴ a change in the environment may affect a small portion of the individuals: stable
• Outline the disadvantages of captive breeding:

  • limits genetic diversity
  • nutritional issues are difficult to manage
  • maintaining the correct environment for survival may be difficult to achieve = expensive
  • individuals cannot adapt to the wild when reintroduced
  • ethical concerns
• Name reasons that affect genetic diversity:

  • captive breeding
  • inbreeding
  • poor gene pool
  • population bottleneck - genetic bottleneck
• Captive Breeding is a form of Conservation Ex Situ
• Define Conservation Ex Situ:

  Conserving an endangered species outside its normal habitat
• Give examples of Conservation Ex Situ:

  • Seed banks
  • Zoos
  • Botanical gardens
  • aquarium
• Outline some advantages of Conservation Ex Situ:

  • organisms are protected from predation and poaching
  • medical assistance provided
  • the genetic diversity of a population can be measured
  • aids research
  • tourist attraction = economic opportunity
  • education
• Outline how Human Population Growth can affect habitat diversity.

  • increase demand of food and shelter
  • increase use of resources
  • deforestation
  • pollution
  • poaching - directly and indirectly links to extinction
• Define Poaching:

  The illegal killing or capture of animals that are not one's own
• Define Monoculture:

  The cultivation of one strain of crop of one species in one area
• Name the types of reasons for maintaining biodiversity.

  • Ecological
  • Genetic Resource
  • Economical
  • Aesthetic
• What is Non-random Opportunistic Sampling?

  Deliberately selecting individuals that fit the criteria based on prior knowlege