Topic 3 - sampling methods Flashcards
what is the abundance scale
the relative representation of a species in a particular ecosystem
what is a beating tray
A pale coloured cloth that is stretched out using a frame. The frame is then placed under a tree or shrub and the foliage is then shaken. invertebrates fall from the tree and land on the cloth
what is a belt transect
like a line transect except but gives more information on the presence or abundance of a species
extend a measuring tape from one side of the habitat to the other
place a quadrat at 0m on the tape
calculate percentage cover of each species
move quadrat along tape
what is the dependent variable
the variable being measured or tested
what is eDNA
environmental DNA is DNA that is collected from a variety of environmental samples such as soil or snow. DNA is collected as organisms interact with the environment
what is homogeneity
a lack of biodiversity
what is a hypothesis
a precise, testable statement of what researchers predict will be the final outcome of the study
what is the independent variable
the variable the experimenter controls or changes and is expected to have a direct impact on the dependent variable
what is kick sampling
when a net is held underwater and the surrounding substrate is disturbed by kicking
used to see species diversity and presence or absence of a species
what is the lincoln index
a statistical measure, provides a way to measure population sizes of individual animal species
uses total population ( figured out ) number of animals captured on the first day number of animals recaptured number of marked animals recaptured
what is a null hypothesis
an assumption or proposition where an observed difference between two samples of a statistical population is purely accidental and not due to systematic causes
name the specialised sampling techniques
tagging ( capture and tag to track )
auditory monitoring
photographing eg camera traps
satellite sensing eg shows clearance of rainforest
DNA databases figures out which species are endangered ( labour intensive )
tracking eg radio tracking , collars. works land and water but must be close to or know species size
indirect methods eg footprints, scratch posts. doesn’t disturb but must be knowledgeable
what is the pit fall trap
( cup in ground and species fall into the cup )
used to sample populations of mobile animals in the ground surface
other species can fall into cup or eat species
what is colonisation media
used for aquatic invertebrates
some species can be monitored by providing suitable habitats for them to live in
what is suber sampling
a more standardised technique then kick sampling
fixed area of riverbed sampled with box like frame riverbed disturbed via trowel or similar tool and stones manually inspected
netting at sides of net opening reduces organisms escaping
