Biodiversity

• Biodiversity

  • Sampling helps see if human activities affect habitat
  • Planning process of major construction, EIA, maintain + minimise damage
  • Environment Impact Assessment (EIA): Effect environment considered when doing eco work; aim min habitat disturbance
  • Measuring:
  • Habitats are too large to count all species + organisms in each
  • Take sample, small area; assumed representative of habitat
  • Sampling Methods…
  • Random
  • Non-random: Systematic, Stratified or Opportunistic

  Key Terms

  • Species richness (diversity): Different species no.
  • Species evenness: Each species abundance
  • Habitat: Place where species live; specific locality, conditions + organisms, well adapted
  • Genetic: Variation between species individuals; all look a little different
  • Genetic diversity: Allele variation + range in species
  • Species: Similar in appearance, anatomy, biochemistry + able to interbreed for fertile offspring; different structurally or functionally
• Simpson's Diversity Index

  • Measure habitat diversity accounts for species richness + evenness of habitat using equation:
  • D = 1-[Σ (n/N)^2]
  • n = number of individuals of a species
  • N = total number of individuals of all species
  • Always get value between 0 + 1
  • High value (close to 1) = more diverse
  • Indicates highly biodiverse habitat w/ high species richness
  • Evenly represented, tends to be stable + can withstand change
  • These habitats should be conserved and not used for development projects
  • Low value (close to 0 ) = less stable + easily damaged by change
  • Habitat dominated by few species
  • Unstable as environmental change (e.g. disease) damaging dominant species pop could change whole habitat
  • Humans often cause biodiversity damage by their activities
• Genetic Biodiversity

  • Genetic biodiversity allele variation; different gene versions
  • Low genetic diversity; species more susceptible to environmental changes - whole pop could be wiped in single event
  • Key Terms:
  • Polymorphism: Gene more than 1 allele (e.g. Hair colour, eye colour + blood type)
  • Monomorphism: Gene has only 1 allele; most genes ‘monomorphic’ to ensure species base structure similar
  • Locus: Where on chromosome alleles located
  • Calc
  • Proportion of polymorphic gene loci = number of polymorphic gene loci/total number of loci