biodiversity🌈🌴🐿 Flashcards
explain importance of sampling in measuring biodiversity of a habitat
- impossible to count every individual
- sample is represetative of the habitat
- sample provides an estimate
what is species evenness?
number of individuals of each species in a habitat
why is species evenness and richness used to assess biodiversity
- both richness and evenness are used to reveal dominance of a species
- high species richness and species evenness are needed for high biodiversity
what does a low simpsons index suggest
- dominance of one/few species
- ecosystem unstable and less likely to cope with change
what is phylogeny and how is it related to classification
- phylogeny is the study of evolutionary relationships between species
- phylogeny is the basis of classification
- common ancestry
- closer relationship= closer taxonomic grouping
- DNA evidence/ amino acid sequence/ base sequence
reasons to conserve a species
- keystone species/impact on food chain
- aesthetic reasons: beautiful
- ecotourism: economic
why is it sometimes necessary to use ex situ conservation
- habitat lost due to climate change
- protection from pathogens
- protection from herbivores/predators
- reproduction difficult in the wild
- competition reduced
- reduced mortality of young
what are the advantages of conserving plants as seeds and not adult plants
- remain viable for long periods
- lower maintenance costs
- large numbers can be stored
- less susceptible to disease
- cheaper to transport
- take up little space
outline an unbiased sampling method to use on grassland
-quadrat
-random sampling method
-2 measuring tapes perpendicular to
each other to make grid
OR
-systematic sampling
-transect
- take 10 samples
- use identification key
- sample at different times in the year
why are estimates of total number of species on earth inaccurate
- some species may recently have become extinct
- new species constantly being formed/evolution ongoing
- some species difficult to distinguish/ scientists may disagree on classification of species
ways to ensure simpsons index value is accurate
- standardisation of technique
- random sampling
- identification key
- survey at different times of year
define biodiversity
- range of species in an area
- range of habitats/ecosystems
- variety of alleles
why is it important to conserve species in particular areas
- tourism
- native species
- part of local food chain
what is considered in an environmental impact assessment for building a wind farm
- size of development
- which species are present in area
- potential damage to species in the area
- potential strategies to minimise impact
how could a population of antarctic fish be conserved
- ban fishing in the area
- limits of numbers caught
- protect habitat
- ex situ/captive breeding
why might it become increasingly more difficult to discover new drugs
- biodiversity is reducing
- global warming
- species which may have been sources of drugs will become extinct
risks of bringing species into a new area
- outcompete native population
- might not be adapted to local conditions
why is the number of species identified by scientists lower than actual number of species
- not all areas explored
- microscopic species difficult to see
- concept of species difficult to define
why is the number of species identified increasing rapidly
-improved identification techniques
if the number of endangered species stays constant as number of species identified increases what does this suggest
conservation techniques working
what does CITES stand for
Convention on International Trade in Endangered Species
aims of CITES
- regulate trade in endangered species
- ensure trade doesnt endanger wild populations
- prohibit wild plant trade
- allow some trade in less endangered species
aims of the Rio convention
- sustainable use of ecosystems
- share genetic resources
- promotes ex situ conservation
- share access to scientific knowledge
- international cooperation
how do organic fertilisers improve crop yields
- add minerals to soil
- nitrate phosphate potassium
- nitrogen for protein
- lack of minerals is limiting factor for growth
inorganic fertilisers are not toxic to organisms but reduce biodiversity suggest how
- promotes growth of one species
- other species are outcompeted
- reduction in soil quality
why reduction in biodiversity will cause problems for agriculture
- loss of genetic variation
- lost genes may have been useful
- eg gene for disease resistance
- fewer pollinators
when conserving species why is it important to get them from different areas
- maintain genetic variation
- reduced chance of disease affecting whole population
- prevent interbreeding
what do plants need phosphate for
nucleic acids
why is nitrogen fertiliser needed
- fertiliser replaces lost nitrogen
- nitrogen removed from soil by plant (depletion)
- fertilisers maintain yield
- nitrogen for amino acids for protein synthesis
factors to consider when selecting individuals for breeding programme
- unrelated
- of reproduction age
- higher proportion of females
- health
how to ensure success of release programme after captive breeding
- make sure individuals are healthy before release
- adequate food supply
- no hunting
- tag individuals to monitor
why might a species decrease in number
- global warming
- change too rapid for adaptation
- outcompeted
- disease
when using sweep net how can you make sample more representative
- standardised seeeping procedure
- use of transect
- sample at different times of year
- sample many times and calculate mean
explain importance of species evenness in determining biodiversity
- number of individuals of each species
- higher species evenness means higher biodiversity
- low species evenness indicates dominance of a species
- used for Simpsons index of biodiversity
environmental impact assessment of motorway through ecosystem
- biodiversity
- endangered species
- reduction in size of habitat due to development
- strategies to minimise damage to species
if there is a high simpsons index how does this affect planning of a development
- high biodiversity
- should be conserved
- development reconsidered
explain critically endangered
likely to become extinct
on verge of extinction
long term ways to preserve species after breeding programme
- ban hunting
- reserves/sanctauries
- breeding sites
- protect habitat from destruction
benefit of genetic diversity
- allows for adaptation to changing environment
- provides variation for natural selection
adaptation of plant in shallow waters
leaves with stomata on upper surface only
what is species richness
number of species in an area
