biodiversity

• the benefit of using the index of diversity instead of species richness is that it takes into account population sizzes of different species in one community
• what is genetic diversity?

  number of different alleles that can be found at a given gene locus within a population
• greater genetic diversity = greater number of alleles at a different given locus
• genetic diversity = no of polymorphic gene loci divided by total number
• systematic sampling:

  • individuals or locations are selected at regular intervals within a target
  • easy to implement
  • often involves line/belt transect
• stratified sampling:

  • some populations can be divided into strata based on characteristics
  • random sample taken proportional to size
• random sampling:

  • selecting individuals by chance
• field data collection techniques:

  • sweep netting = catch airborne insects
  • pitfalls = catch organism that falls into hole
  • pooters = retrieve targeted organisms that have been identified for selection
• measuring plants in frame quadrats:

  • density
  • frequency
  • percentage cover
• state the difference between species richness and evenness:

  • species richness = number of species living in a certain area
  • species evenness = comparison of number of individuals living in a community
• what is the difference between in situ and ex-situ conservation:

  • in-situ = inside natural habitat = wildlife reserve
  • ex situ = outside natural habitat = zoo
• factors affecting genetic biodiversity (increase):

  • mutations
  • inbreeding
• factors affecting genetic biodiversity (decrease):

  • selective breeding
  • captive breeding programmes
  • artifical cloning
  • genetic bottleneck
  • founder effect\
• Human influence on biodiversity:

  • deforestation
  • agriculture = use pesticides
  • climate change
• aesthetic reasons to maintain biodiversity:

  • provides inspiration to writers
  • help recovery from stress
  • enrichment
• economic reasons to maintain biodiversity:

  • monoculture can leach nutrients causing crops to become poorer in yield = helped by crop rotation
  • harder to manufacture products in the future
  • allow countries to grow crops and feed population leading to economic independece
• ecological reasons for maintain biodiversity:

  • protect key species to prevent collapse of ecosystem
  • sustainably obtain resources we need
  • maintain resources that could result in development od new medicines
• conservation agreements:

  • CITES = regulate international trade
  • Rio convention = maintain biodiversity
  • Countryside stewardship scheme = flood risk management and reduction of water pollution