Topic 3

Question 1

Biodiversity

Answer 1

Amount of biological or living diversity per unit area

Consists of species, habitat, and genetic diversity.

High biodiversity doesn’t ALWAYS mean a healthy ecosystem

Question 2

Species diversity

Answer 2

The variety of species per unit area

Product of 2 variables: number of species (richness) and their relative populations (evenness)

Question 3

Habitat diversity

Answer 3

The range of different habitats in an ecosystem or biome

Question 4

Genetic diversity

Answer 4

Range of genetic material present in a gene pool or population of a species

Question 5

Pros and cons of biodiversity

Answer 5

Pros of area w high biodiversity:

• resilience and stability against disasters
• genetic diversity to resist disease
• deep roots to help cycle nutrients

Limitations of using this as an indicator of health:

• could be result of fragmentation or succession
• Challenging to manage for grazing
• some stable communities have few plants species, so there’s exceptions

Question 6

Hotspot requirements

Answer 6

Lost over 70% of habitat

Contain more than 1500 endemic plant species

Question 7

Hotspot critiques

Answer 7

Focus only on plants. Doesn’t represent total richness or diversity. Focus on lost habitats, not loss that’s still happening. Doesn’t consider genetic diversity. Doesn’t consider the value of resources

Question 8

Threats to biodiversity

Answer 8

Pollution, habitat loss and degradation, species over exploitation, invasive species and disease, climate change, habitat fragmentation, introduced species, modern agriculture

Question 9

Factors that maintain biodiversity

Answer 9

Complexity of ecosystems (food webs)

Stage of succession (later stages more stable)

Question 10

What makes a species prone to extinction

Answer 10

Narrow geographical range
Small/declining population
Low pop density in large territory
Large body (10% rule)
Low reproductive potential

Question 11

Why are island organisms more vulnerable to extinction

Answer 11

Smaller populations, high degree of endemic populations, low genetic diversity, vulnerable to introduced species

Question 12

Why conserve biodiversity

Answer 12

Sources of food, ecotourism, biorights

Question 13

Conservation biology

Answer 13

The sustainable use and management of natural resources

Anthropocentric viewpoint

Question 14

Preservation biology

Answer 14

Attempts to exclude human activity in areas that have not yet been encroached

Ecocentric viewpoint

Question 15

Species based conservation approaches

Answer 15

Captive breeding and zoos, flagship species, botanical gardens and seed banks