Biodiversity

• What are the 3 levels of biodiversity?


  habitat

  genetic

  species
• Random sampling

  No particular system.

  usually randomly generated numbers are used as coordinates
• advantage of random sampling

  not biased
• Disadvantage of random sampling

  -Species in low presence may be missed

  -not covering all areas of a habitat equally
• opportunistic sampling 


  making decisions based on prior knowledge/ during the process
• advantage of opportunistic sampling


  easier and quicker
• disadvantage of opportunistic sampling

  • biased
  • large/colourful species entice researcher- causing an overestimate
• stratified sampling

  dividing habitat into areas which appear different
• advantage of stratified sampling

  -all different areas of habitat sampled

  -species not underrepresented
• disadvantage of stratified sampling

  over-representation of same areas in sample
• systematic sampling 


  samples taken at fixed intervals
• advantage of systematic sampling

  useful for clear gradients in environmental factors
• disadvantage of systematic sampling

  only species on line/belt recorded, other species missed- underestimate
• what are the 2 types of transects?

  -continuous

  -interrupted
• what techniques can be used to sample animals?

  -pooter

  -sweep nets

  -pitfall trap

  -kick sampling

  -tree beating
• what techniques can be used sampling plants?

  -frame quadrats

  -point quadrats
• Why is sampling important?

  Can’t study the whole population so using a representative sample allows us to investigate the population easily
• threats to biodiversity 


  -human population growth- overexploitation

  -agriculture

  -global warming/ climate change
• How is agriculture effecting our environment-selective breeding?

  Selective breeding leads to lack of genetic diversity makes crops more susceptible to pests and diseases
• how does global warming effect out biodiversity?

  -species move to higher altitude and cant adapt- causes extinction

  -coral bleaching increased

  increased co2 dissolved in ocean
• species richness 


  The number of species within a community
• Conservation for economic reasons

  -regulation of atmosphere and climate

  -recycling nutrients

  -purification and retention of water

  -crop pollination

  -formation and fertilisation of crops
• conservation for aesthetic reasons

  attracts tourists
• conservation for ecological reasons


  -develop new crop varieties

  -provides genetic sources to maintain existing wild species

  -wild varieties of species used for cross breeding
• why is it a problem when species are lost?

  -loss of pollinator species

  -loss of predator species

  -disruption to food chain- some species lost food
• how does soil depletion effect the economy?

  -monocultures create more money- increases yield

  -nutrients used up- soil depletion occurs

  -increased fertilisers bought
• What increases biodiversity?


  -mutations

  -interbreeding- alleles will be transferred
• what is decreasing biodiversity?

  -selective breeding

  -captive breeding

  -rare breeds

  -artificial cloning

  -natural selection

  -genetic drift
• what creates genetic diversity?

  difference in alleles
• are species with high biodiversity more or less likely to adapt to changes in the environment?

  more likely to
• Ex situ examples

  Seed banks

  botanic gardens

  zoos
• In situ 


  Keeping species in natural habitat
• Ex situ 


  Protecting endangered species outside of natural habitat
• What does CITES stand for?

  Convention on International Trade in Endangered Species of Wild Fauna and Flora
• What is the aim of cites?

  control the trade of endangered species and their associated products
• What does css stand for?

  Countryside stewardship scheme
• What is the aim of css/ environmental stewardship scheme?

  Provide funding to farmers and private land owners who used environmental management strategies to protect and increase their Natural biodiversity
• Advantage of in situ 


  Kept in original habitat

  habitats protected

  helps scientific research
• Disadvantage of in situ

  -Encourages ecotourists and poaches- disturbance

  -requires co ordination of different organisations

  -conflict of interest with those living and working in the area
• Advantage of ex situ

  -Animals are safe from hunting

  -selective breeding used to increase genetic diveristy