Biodiversity Flashcards
what are the different levels biodiversity may be considered at ?
habitat, species, genetic
what is habitat biodiversity?
range of habitats where different species live
what is species biodiversity?
range of organisms found in a habitat, high species evenness and richness
what is genetic biodiversity ?
variation between individuals belonging to the same species. ensures we don’t all look the same and can create breeds within a species
what is species eveness ?
degree of representation of a species, how even the species are
what is species richness?
the number of species
how is sampling used in measuring the biodiversity of a habitat?
select a small portion of the habitat and study that carefully, multiply this up to size of the habitat to create an estimate. more practical method of measuring biodiversity by observing the species present
what are the 4 types of sampling used?
random, opportunistic, stratified, systematic
how is random sampling carried out ?
sample sites are randomly selected by random generally numbers (co ordinates)
how is an opportunistic sample carried out?
sample deliberately put in an area they know contains a particular species
how is stratified sampling carried out ?
dividing a habitat into areas that appear to be different
how is systematic sampling carried out?
samples are taken at fixed intervals
what is the importance of sampling a range of organisms in the habitat?
makes it more representative of the whole habitat
what is the preparation for sampling a habitat?
suitable clothing, suitable footwear, apparatus needed for sampling, equipment for recording observations, key to identify species, phone to record specimens or grid location
how can you randomly sample plants
co ordinates to place quadrats
how can you calculate percentage cover of a species?
use a point frame
how can an abiotic factor be measured in a habitat?
interrupted or continuous belt transect
how can you sample large animals?
observation
what are 5 methods for catching invertebrates ?
sweep net, stout net, poster, pitfall trap, tullgreen funnel, light trap
how can you trap small animals to measure population size?
Longworth trap, mark and recapture technique
how to measure the total population ?
name the Cs
(C1 X C2) / C3
C1= number captured first time
C2= number captured 2nd time
C3 number already marked animals recaptured
how could the calculated total population value be effected (decreased) ?
animals learn the trap is harmless and contains food so will increase C3 and decrease total population
how could the calculated total population value be effected (increases) ?
animals stay away from the trap as they know they will get caught so decrease C3 and increase total population
how are birds and small animals tagged?
birds ringed and small animals tagged
how can you measure species richness?
counting all species present
how can you measure species evenness?
percentage cover for plants
what can we use to measure the diversity of a habitat?
simpsons index