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1. Introduction

Biodiversity , a word derived from biological diversity , is the variety of all life forms: the different plants , animals and microorganisms , their genes and the communities and ecosystems of which they are part . Biodiversity is usually recognised at three levels : genetic diversity , species diversity and ecosystem diversity . Biodiversity loss is the local or global extinction of an allele or species .(Steffen,2009)

Austrlia is separated from other countries so when the biodiversity loss happen in Australia , it could be more serious than in other countries . In this report , two causes of biodiversity loss are demonstrated is climate change and human actions in the past and present which their effects and comparison .

2. Two causes

2.1 Climate change

2.1.1 Effects

Evidences of the effects of climate change is verified by variety researches . The first one would be the rising of the sea level (1.8mm/per year 1960-1983 and 3.1mm/year afer that time ) and tropical happened because of climate change , which cause the loss of wetland , low-lying island and coastal ecosystems . The climate change also lead to the increasing of global average temperature , about 2oC so it is hard for animals to adapt these changes . As the results , a lot of species will become extinct . Morover , a lot of areas were highly vulnerable like

Great Barrier Reef , the Australia Alps , the Queensland Wet Tropics , Kakadu wetland ,ect. with switches in genetic composition , changesd some birds’ migration patterns , altered life cycles of some species and ruduced the reduction rat of other ,ect. ( Healey,2001,p7,Steffen,W et al,2009)

2.1.2 Compare

To support the effects of climate change on the Austarlia’s biodiversi...

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...lacial maxima , time of peak cold , about 90 species dissappeared . As well as , 50 thousand years later , other species disappeared but it still long before the time which first Aborigines arrived . Thus Woe has different conclusion for the major cause of the extinction .

3. Conclusion

In conclusion , both climate change and human actions impact on Australia’s biodiversity but each of them effect in a different way . While human actions are more likely cause the extinction of animals in the past like causing the extinction of giant animals 40,000 years ago , climate change lead to the loss of biodiversity in present such as the loss of wetlands or low islands. Although controlling the impacts of climate change can a challenging for the whole word , reducing its impact can be done by finding out the reason of it and solve those problem .