Flashcards in Biodiversity Deck (10):
What is sampling?
Taking measurements of a limited number of individual organisms present in a particular area
What does the abundance of an organism tell us
The number of individuals of a species present in an area
What is random sampling
Means selecting individuals by chance
What is non random sampling
When the sample is not random
What are the three main techniques if non random sampling
Explain opportunistic sampling
Weakest form of sampling. Uses organisms the are conveniently available.
Explain stratified sampling
Population can be divided into a number of strata based in particular characteristics. A random sample is then taken from each strata proportional to its size.
Explain systematic sampling
Areas within an overall population are identified and sampled separately. Often carried out using a line or belt transect.
What is sample bias
Selection may be biased. May be by accident or deliberate. Effects may be reduced using random sampling.