11 - Biodiversity Flashcards

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1
Q

What are the different levels of biodiveristy?

A

habitat biodiversity
species biodiversity
genetic biodiversity

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2
Q

What is habitat diversity?

A

the number of different habitats in an area

  • e.g one area could contains lots of habitats
  • sand dunes
  • woodlands
  • meadows
  • streams
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3
Q

What is species diversity?

A

the number of different species (species richness) and abundance of each species (species evenness) in an area.

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4
Q

what is species richness?

A

the number of different species in an area.

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5
Q

what is species evennness?

A

the relative abundance of each species in an area.

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6
Q

what is genetic diversity?

A

the variation of alleles within a species (or a population of species).

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7
Q

How can sampling be used to measure biodiveristy?

A
  • choose an area to sample (small area within a habitat).
  • count the number of individuals of each species.
  • repeat the process many times to get have a better representative of the whole habitat.
  • use the results to estimate the total number of species and individuals in the habitat.
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8
Q

What tools do you use to sample different organisms for when measuring biodiversity?

A
plants: quadrat
flying insects: sweep net
ground insects: pitfall trap
insects: pooter
aquatic animals: net
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9
Q

Why are samples taken to measure biodiversity in a habitat?

A
  • too time consuming to count every individual in a habitat.

- samples provide an estimate about the whole habitat.

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10
Q

what is random sampling?

A
  • random sampling means selecting individuals by chance.
  • each individual has an equal chance of selection.
  • avoids bias
  • measuring tapes to divide area into a grid.
  • random number generator to generate random coordinates.
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11
Q

what is non-random sampling?

A

sample is not chosen at random.

systematic sampling
opportunity sampling
stratified sampling

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12
Q

what is systematic sampling?

A
  • samples are taken at fixed intervals.
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13
Q

what is opportunistic sampling?

A
  • samples are chosen by the investigator.
  • bias
  • simple to carry out
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14
Q

what is stratified sampling?

A

when different areas within a habitat are identified and sampled separately in proportion to their part of the habitat as a whole.

  • different sub groups are called strata based on a particular characteristic.
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15
Q

reliability of sampling

A

never 100% reliable or representative

there may be bias or by chance the may not be representative.

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16
Q

Simpson’s index of diversity

A

used to calculate the biodiversity of a habitat

  • takes into account both species richness and evenness.
  • value between 0 and 1.
  • 0 no diversity
  • 1 infinite diversity.
  • the greater the species evenness and richness, the higher the value.
17
Q

genetic polymorphism

A
  • used to measure genetic diversity.
  • polymorphism describes a locus that has two or more alleles.

proportion of polymorphic gene loci = number of polymorphic gene loci / total number of loci.

18
Q

examples of suitable populations

low genetic diversity

A

zoos (captive breeding)
rare breeds
pedigree animals

19
Q

Factors affecting biodiversity

A
  • human population growth
  • agriculture (monoculture)
  • climate change
20
Q

factors that affect genetic biodiversity?

A
  • mutations in DNA of an organism
  • interbreeding between different populations
  • selective breeding
  • captive breeding
  • natural selection
21
Q

How does human population growth affect biodiversity?

A
  • deforestation, destroying habitats
  • over exploitation of resources
  • urbanisation, can isolate species
  • pollution can kill species or destroy habitats.
22
Q

How does agriculture (monoculture) affect biodiversity?

A
  • deforestation to increase land available for growing crops.
  • use of chemicals such as insecticides/herbicides
  • monoculture: growing a single variety of a single crop. Greatly lowers biodiversity as only one type of plant is present.
23
Q

How does climate change affect biodiversity?

A

pollutants caused by human activity.

  • greenhouse gases can cause global warming, which causes other types of climate change such as changing rainfall patterns.
  • climate changes affect different areas of world in different ways: warmer, colder, wetter, drier. All have an affect on global biodiversity.
  • climate change can make an area uninhabitable or inhabitable.
  • can cause increase or decrease in range of some species in the area.
  • increase/decrease diversity.
  • can cause migration. Decreases biodiversity in original location, increases biodiversity in new location.
  • if climate change occurs too fast or organisms cannot migrate, this can cause a species to become extinct. Decreases biodiversity.
24
Q

Why do we maintain biodiversity?

A

ecological reasons:

  • protecting keystone species (often predators).
  • maintaining genetic resources (e.g plants for medicine)

economic reasons:
- to reduce soil depletion caused by continuous monoculture.

aesthetic reasons:

  • protecting landscapes
  • protecting exotic animals
  • because they are nice to look at.
  • attracts tourism / increases tourism

ecotourism

25
Q

Why does a change in one organism in an ecosystem have drastic effects on the ecosystem?

A
  • organisms in an ecosystem are interdependent.
  • disruption of food chains
  • disruption of nutrient cycles.
26
Q

What is in-situ conservation

A

protecting species in their natural habitat.

e.g marine conservation zones, wildlife reserves

27
Q

What is ex-situ conservation

A

protecting a species by removing them from their natural habitat and placing them in a new location

e.g zoos, seed banks, botanic gardens.

28
Q

what are captive breeding programmes?

A

they produce offspring of species in a human-controlled environment.

29
Q

Rio convention on biological diversity (CBD)

A
  • develop international strategies on the conservation of biodiversity and how to use animal/plant resources in a sustainable way.
  • international law that conserving biodiversity is everybody’s responsibility.
  • guidance to governments on how to conserve biodiversity.
30
Q

Convention on international trade in endangered species (CITES agreement)

A
  • increase international cooperation in regulating trade in wild animals and plant specimens.
  • illegal to kill endangered species in all countries.
  • illegal to trade in products made from endangered animals.
  • raises awareness of threats to biodiversity through education.
31
Q

the countryside stewardship scheme (CSS)

A
  • aim to conserve wildlife and biodiversity.
  • 10 year agreements to pay landowners who followed management techniques.
  • since 2000, 10000 agreements. Populations of various species have begun to regrow.