Unit 3 Outdoor and Environmental Education

3.1.1 Australian Outdoor Environments

Before Humans

Continental Drift

– 40 to 50 million years ago Australia split off from Antarctica

– Some species of animals and plants have remained common from this earlier break up of the super continent…Pangaea….that became Gondwana and eventually Australia. Some examples include:

Banksia tree on the left is found in Australia, South Africa and India

•

                                                                                                                      Beech Tree above is found in Australia ,New Guinea and South America

The uniqueness of the Australian environment has been shaped by three main factors:

• Biological Isolation• Geological Stability• An erratic climate

Biological Isolation

• Over the past 40 million years since separation from Gondwanaland the flora and fauna have been able to evolve in isolation

Geological Stability

• Volcanoes and glaciers have not been active for a very long time. The land mass is made up of very old rock with very poor soils. The soil has been subjected to much wind and erosion. The poor state of the soils has had an influence on the flora and fauna.

An erratic climate• There seems to be a

swing between climate extremes. Australia moves from long lean droughts (El Nino) to flooding rains (La Nina). This erratic climate has affected the reproductive cycles and survival rates of the flora and fauna.

Fire and Drought

• Fire has had a significant impact on the Australian landscape it has greatly influenced the type of vegetation that now predominates the continent.

FIRE• As Australia became drier tropical forests retreated

to gullies and valleys • Arid areas spread helped by the higher incidence of

naturally occurring bushfires• Increased frequency of fire led to many plant and

animal adaptations• Fire frequency and intensity has increased since

European settlement : Why?

Work task oneAdaptations of native plants and animals to the unique and often harsh Australian environment

Work task twoDescribe the role of fire in the Australian

environment