Diversity and ecological stability

Question 1

Simpsons diversity index

Answer 1

D=N(N-1)/En(n-1)
D=diversity
N=Total number of all species
E=Sum of
n=total number of organisms in a particular species

Question 2

Importance of assessing species diversity

Answer 2

Monitoring environmental change
Monitoring habitat damage
Monitoring success of conservation efforts

Question 3

Calculation to describe biodiversity

Answer 3

Simpsons diversity index

Question 4

Reasons why not all species have been discovered

Answer 4

Not fully researched ecosystems
Difficulty in identifying different species
Many plants can only be identified by flowers
Males and females may only come together for breeding

Question 5

Population dynamics

Answer 5

Factors affecting birth rates

Factors affecting mortality rates

Question 6

Calculating population size

Answer 6

Population size= +births +immigrants -deaths -emigrants

Question 7

Factors affecting birth rates

Answer 7

Natural reproductive cycles
Herring produce many young because most of them will die before reproduction
Elephants produce very few young because very few will die before reproducing

Question 8

Factors affecting mortality rates

Answer 8

Density independent factors

Density dependent factors

Question 9

Density independent factors

Answer 9

Drought
Flood
Volcanic eruptions

Question 10

Density dependent factors

Answer 10

Food supply
Disease
Become more important as population increases until a balance with birth rates is reached

Question 11

Homeostatic population regulation

Answer 11

Carrying capacity
Predator:prey relationships
Artificial population control

Question 12

Carrying capacity

Answer 12

The maximum population that can be sustainably sustained
Populations above the carrying capacity become more susceptible to density dependent factors
Populations below the carrying capacity are less susceptible to density dependent factors

Question 13

Homeostatic

Answer 13

An example of dynamic equilibrium

Question 14

Predator:prey relationships

Answer 14

Example of population self-regulation
Found in areas where there are few prey species for a single predator
A reduction in one prey species will cause a reduction in the predator species

Question 15

Artificial population control

Answer 15

Also known as culling/ selective killing
Necessary to conserve species or habitats
Mainly found where the natural predator has been removed
Eg. culling deer where wolves have gone extinct