BIODIVERSITY

• biodiversity=


  variety of living organisms in an area
• habitat


  place where an organism lives
• community


  all populations of different species in a habitat
• High biodiversity= lots of different species
• LOCAL BIODIVERSITY= variety of different species living in a small habitat eg. pond or meadow
• GLOBAL BIODIVERSITY= Variety of species on earth
• Ways to measure biodiversity

  • species richness - take random samples of a community and counting number of different species
  • Index of diversity - equation that uses both number of species and abundance of each species , higher the number = more diverse an area is
• define the index of diversity

  relationship between the number of species in a community and the number of individuals in each species
• evaporation = inc conc of pesticide
• How to ensure index of diversity was accurate

  • Random samples
  • large number of samples
  • Continue sampling until stable running mean
• Why does biodiversity decrease In larger farming field

  • more centre
  • Less hedge
  • Fewer species
• advantage of replanting hedges on fields

  • more pollinators= healthier and larger yield of crop
  • inc in predators of pests= inc in yield of crop
  • greater biodiversity therefore inc in predators of pest
• methods to reduce biodiversity

  • woodland clearance
  • hedgerow clearance
  • pesticides
  • herbicides
  • monoculture