SP 3.2 Flashcards
Biodiversity →
Considered at three levels: genetic diversity, species diversity and ecosystem diversity.
Genetic Diversity →
Variety of genetic information contained in all the individual plants, animals and micro-organisms.
Species Diversity →
it is literally the divers range of different species in an environment.
More specie diversity the more robust the ecosystem
Ecosystem Diversity →
Ecosystem diversity is the variety of habitats, communities and ecological processes present within ecosystems.
Extent →
The smaller the ecosystem the more vulnerable.
The most important is the microclimate variations created by the physical features of an area.
Extent (example) →
The Great Barrier Reef coral ecosystem covers 348 000km2 whereas the Intertidal Wetlands at Homebush Bay covers 0.58km2.
Location →
effects ecosystem functioning. High familiarisation = more vulnerable an ecosystem is to change.
Location (example) →
Eucalyptus trees are only found in certain areas of Australia and it is the only food source for koalas. Therefore, if there is damage or habitat loss within Eucalyptus forests it places koalas at extreme risk.
Linkages →
Is related to species diversity. The greater the level of interdependence the greater the ability to absorb change.
Linkages (example) →
Any reduction on the supply to Krill will directly affect whales. Primary consumers with highly specific food shortages are vulnerable to disturbances.
Ecosystem Resilience →
Resilience is the ability of an ecosystem to adapt to a changing environment and to restore function following an episode of natural or human induced stress.
Natural Stress →
Gradual Change
- Immigration or invasion of a new species
Catastrophic Change
- Natural disasters (Volcanic eruption)
Natural Stress Impacts →
Organism Level
- fewer to no offspring with genetic defects
Population Level
- population levels increase or decreases
Ecosystem Community Level
- disruption of energy
- disruption of chemical cycles
- disruption of species diversity
Human Induced Modifications →
→ Removal: the clearance of native vegetation and disruption of ecological processes
→ Replacement: the removal of native vegetation and its replacement with agriculture, horticulture and plantation forestry
→ Utilisation: the exploitation of native vegetation for forestry, pastoralism and recreation
→ Conservation: the maintenance of natural vegetation for conservation with minimum deliberate modifications of natural processes – lands designated to national parks, nature reserves
Intentional Change →
→ Incomplete knowledge of ecosystem functions
→ Intentional modifications but unintended consequences
- Aboriginals burnt bush
