Quantifying And Measuring Biodiversity

Question 1

What does vegetation affect?

Answer 1

Temperature, humidity, light and wind speed

Question 2

What controls biodiversity?

Answer 2

In the environment it’s the physical structure and the nutrition/resources that affects and controls biodiversity

Also competition

Question 3

What does the plant dominance index measure and who invented it?

Answer 3

Gives a measure of the competitive ability of plant species and tells you if it will take over an environment

Phillip Grime

Question 4

Give some examples of dominant plant species

Answer 4

Nettle (Urtica dioca)

Bracken (Pteridium aquilinium)

Rose bay willow herb

Question 5

What 4 aspects are taken into account when calculating the dominance index?

Answer 5

1. Growth rate
2. Potential height
3. Potential for lateral spread
4. Litter production

Question 6

How do you calculate the dominance index?

Answer 6

Species are given a score of 1-5 on each character

The score is summed and divided by 2 to give a score out of 10

Question 7

Give an example of controlling plant dominance

Answer 7

Rhinanthus minor (Hay rattle)

Prevents grasses in meadows becoming too dominant, allowing other plant species to grow

Question 8

What is the diversity index?

Answer 8

Measure of the number of species/families/genera and number of individuals of each

Evenness= dominance of species

Question 9

On the k-dominance curve what do you plot and where?

Answer 9

Different species: x axis

Abundance of each species: y axis

Question 10

What does Shannon diversity calculate?

Answer 10

The proportion of all individuals that belong to each species

Question 11

Where do natural communities usually fall on the Shannon diversity?

Answer 11

H’= 1.5-3.5

Question 12

What does Simpson dominance index measure?

Answer 12

The degree of dominance by a few species in the sample

Question 13

What does island biogeography take into account?

Answer 13

Rates of migration and dispersal
Controls on species richness
Isolation
Relationship between the number of species, the size of the island and the distance from neighbours

Question 14

What is colonisation and extinction dependent on?

Answer 14

The emergence of new ecosystems

Linkage between plants and animals

Question 15

Give an example of a case study that demonstrates colonisation

Answer 15

Rakata

Largest remnant of volcanic eruption of Krakatau 1883

Also Hawaiian islands