biodiversity Flashcards
definition of diversity
variety of living organisms in an area
definition of species
a group of organisms able to breed to produce fertile offspring
definition of habitat
the area where the population of species lives
what 3 things is biodiversity considered by
-habitat diversity
-genetic diversity
-species diversity
what is species richness
the different number of species in an area
what is species eveness
the relative abundance of each different species within the community
what is the importance of measuring biodiversity
enables comparisons to be made between different areas and in the same area at different times
what is random sampling
when sample sites have been selected randomly
what is non-random sampling
when sites have been selected with a purpose
benefits and negatives of stratified sampling over random
stratified ensures all different areas are sampled but it may lead to an over representation of some areas and species
what is sweep netting
small insects get caught in net when swept through the vegetation. a pointer stops insects from flying away
positives and negative’s of random sampling
-ensures that the data is not biased by selective sampling
-may not cover all areas of a habitat equally and underestimate of biodiversity
positives and negatives of opportunistic sampling
-easier and quicker than random
-may be biased- overestimate of bio diversity
what is opportunistic sampling
researcher makes sampling decisions based on prior knowledge
what is stratified sampling
dividing a habitat into areas which appear different and sample them each differently
positives and negative’s of stratified sampling
-ensures that all different areas are sampled
-may lead to over-representation of some areas
what is systematic sampling
when samples are taken at fixed intervals across the habitat
positives and negative’s of systematic sampling
-useful when the habitat shows a clear gradient in some environmental factors
-only the species on the line can be recorded. missing species
what is an allele
a version of a gene
what is a locus
the position of a gene on a chromosome
what is a polymorphic gene locus
a locus that has more than two alleles
factors affecting biodiversity
-deforestation
-agriculture
-global warming
-mining
-pollution
-over exploitation
what is monoculture
growing one type of crop
what is genetic erosion
selecting for specific breeds means other breeds die out
how does the loss of genetic diversity affect species
crop is highly susceptible to diseases and pests
why are habitats hard to restor
harder to restore in different conditions and harder to adapt
what is extinction
when the last living member of a species dies
how does the human population growth effect biodiversity
-alter ecosystems to provide ourselves with food
-we destroy and fragment
-we pollute u
what is a pitfall trap
trap in soil which catches small animals when they walk over it
what is a tulgren funnel
leaf litter is placed in a funnel. a light above the litter drives the animals downwards
what is light trap
light trap collects flying insects
how does the proportion of polymorphic gene loci affect diversity
the higher the proportion of polymorphic gene loci, the larger the genetic diversity within the population
what is the value for high and low diversity with the simpsons index
lower biodiversity- value closer to 0
higher biodiversity- value closer to 1
how can u ensure your sample is representative
take a large sample
use random sampling
what is a point quadrant
horizontal bar with holes along it
what is a frame quadrant
a square frame of a known size
what are pooters
two tubes connected to a closed pot. create suction on the tube which draws the insect into the pot
reasons to maintain biodiversity
ecological
economical
aesthetic reasons
ethical
what is the ecological reason to maintain biodiversity
removal of a habitat also removes food sources for animals. all organisms are interdependent on each other so a loss of one species effects others
what is the economic reason to maintain biodiversity
-tourism relies on people visiting an area of natural beauty
-many medicines use plants
-plants reduce soil depletion
-resources like wood for fences ect
what is in situ
within the natural habitat
what is ex situ
not within the natural habitat
what is the aesthetic reason to maintain biodiversity
protecting landscapes: enjoying the natural beauty of the planet
-beautiful creatures
what is the ethical reason to maintain biodiversity
they have the right to exist
why is it important to collect organisms from several different sites
-maintains genetic variation and gene pool
-reduce the chance of future disease affecting whole population as there is more variation
-reduces inbreeding
-maintains varieties
what does CITES do
-regulate and monitor endangered species
-ensures international trade does not endanger wild population
-prohibit trade in wild plants
-allow trade in less endangered species
what does the Rip convention do
-replant trees, fishing quotas
-share genetic resources
-share access to scientific knowledge
-promotes ex situ conservation
advantages of ex situ
-protected from predation and poaching
-health can be monitored and assisted
-genetic diversity of the population can be measured
-selective breeding can be carried out to increase genetic diversity
disadvantages of ex situ
-a captive population is always likely to have a limited genetic diversity
-animals can be exposed to diseases
-correct environmental conditions may be hard to achieve
-nutritional issues can be difficult to manage
advantages of in situ
-species are conserved in their natural environment
-permanently protects biodiversity
-facilitates scientific research
-may be possible to improve and restore the ecological integrity
disadvantages of in situ
-endangered habitats may be fragmented
-population may have already lost much of its genetic diversity
-area can act as a honey pot for tourists and poachers
advantages of seed banks
-seeds are viable for a long time
-don’t take up a lot of space
-easy to transport
-less vulnerable to disease
