4b

Question 1

Species richness

Answer 1

Number of individuals per species

Question 2

Abundance

Answer 2

Number of individuals per species

Question 3

Two main models

Answer 3

Niche apportionment

Neutral theory

Question 4

Ecological niche

Answer 4

Totality of adaptations of a species to the biotic and abiotic factors

Question 5

Niche breadth

Answer 5

Range of resources exploited by a species occurring together

Question 6

Niche overlap

Answer 6

Range of resources used by two species

Question 7

Niche apportionment theory

Answer 7

McArthur 1957

Assumption that niche structure is hierarchical

Question 8

Neutral theory

Answer 8

Hubble 2001
All species in a community is ecologically similar
Species arise at random through mutation
As individuals dies they are replaced by random individuals
Communities are saturated with species
Violates most observations of competition

Question 9

Disturbance

Answer 9

Disruption to ecosystem - fire, flooding, human

Does affect biodiversity in general

Question 10

Nutrient availability effects on biodiversity

Answer 10

Inputs of nutrients = human = agriculture

Algae blooms = lack of oxygen for such in lakes

Question 11

Threats to biodiversity

Answer 11

1. Local pollution (pesticides, light)
2. Atmospheric pollution (eutrophication)
3. Land use (grazing)
4. Habitat loss and fragmentation
5. Invasive species
6. Recreation (human)