Biodiversity definitions

• biodiversity


  the number of different species in an area

  the variety of organisms and habitats
• habitat biodiversity


  the number of different habitats found within an area
• species richness


  the number of different species present in a habitat
• species evenness


  a comparison of the number of individuals of each species living in a community
• community


  all the populations of living organisms in a particular habitat
• genetic biodiversity


  the variety of genes that make up a species
• habitat


  the place where a population lives
• what do you use to measure light intensity

  light meter
• what is light measured in

  lux
• what is wind speed measured with

  anemometer
• what is wind speed measured in


  m/s
• what is relative humidity measured with

  humidity sensor
• what is humidity measured in

  mg dm cubed
• what causes the genetic biodiversity of a species to increase?

  mutation- new allele are made

  interbreeding between different populations- transfer of alleles (gene flow)
• what causes the genetic biodiversity of a species to decrease?

  Selective breeding

  Captive breeding

  Artificial cloning (asexual reproduction)

  Natural selection (only advantageous allele passed down)

  Genetic bottlenecks (only some survive to an event or change)

  Founder effect (new colony made- isolated)

  Genetic drift (due to random nature of alleles being passed down)
• in situ conservation advantages

  maintains the evolutionary adaptations: enables a species to adapt continually to changing environment

  maintains interdependent relationships

  cheaper
• examples of active management techniques used in wildlife reserves

  control grazing

  control poaching

  removal of invasive species

  halting succession

  restrict human access

  reintroduction of species
• problems associated with reintroducing species back into the wild

  disease- resistance to disease may be lost in captive bred animals

  genetic- the genetic makeup of captive bred animals may become very different to the wild animals, so they can no longer inter-breed

  habitat- the habitat threshold may already be met, so it can no longer support new animals competing for space and food

  behaviour- learned behaviours such as hunting for food may not be present in captive bred animals
• explain the benefits of maintaining biodiversity to agriculture

  Genetic variation/ higher number of alleles:

  Used for selective breeding to create crops that can cope with climate change

  Provide a habitat for pollinators

  Source of a new medicine for livestock
• how to make a biodiversity investigation more valid- REPRESENTATIVE


  More transects in different parts of areas

  Collect at different times of day and year

  Use a butterfly net to capture individuals

  Use a key to identify species