RP12-effect of different variables on species distribution

Question 1

list 3 abiotic factors

Answer 1

-temperature
-rainfall
-humidity

Question 2

list 3 biotic factors

Answer 2

-predation
competition for resources
-disease

Question 3

Outline the procedure to this practical

Answer 3

-choose an area to take samples from, use random number generator to generate a large number of co-ordinates
-use two tape measures to create a set of aces off which co-ordinates can be read
-place the quadrat at each of the co-ordinates
-records percentage cover for the chosen species
-at each co-ordinate, a measure of the independent variable should be taken, i.e record water supply in soil sample with desiccator

Question 4

why should a random number generator be used

Answer 4

to avoid bias in random sampling

Question 5

state the formula for the mark-release-recapture method

Answer 5

population size = no. in 1st sample x no. in 2nd sample / no. marked in 2nd sample

Question 6

state the assumptions when using the mark-release-recapture method

Answer 6

-no births, deaths or immigrations
-random mixing of marked individuals with population
-marking does not affect individual or make them more vulnerable