Biodiversity. (Department of Sustainability, Environment, Water, Population and Communities)

Transcription

1

2 Biodiversity Biodiversity is the variety of life: the different plants, animals and micro-organisms, their genes and the ecosystems of which they are a part. (Department of Sustainability, Environment, Water, Population and Communities)

3 Past Mass Extinctions The Permian Triassic Event Loss of ~ 95% of all species Evidence for a drying climate

4 Past Mass Extinctions The Permian Triassic Event Loss of ~ 95% of all species Evidence for a drying climate Possible causes possible meteorite impacts (sites to be confirmed) lava outpourings (Siberian Traps) catastrophe theory

5 The K/T event Past Mass Extinctions Loss of ~80% of all species Evidence for a cooling climate

6 The K/T event Past Mass Extinctions Loss of ~80% of all species Evidence for a changing climate Possible causes Asteroid impact (Chicxulub Crater) Lava outpourings (Deccan Traps)

7 Climate Change and Biodiversity Biodiversity changes over time are strongly linked to climate change

8 Climate Change and Biodiversity Biodiversity changes over time are strongly linked to climate change The Late Ordovician mass extinction (~450 million years ago) =the second-largest mass extinction

9 Climate Change and Biodiversity Biodiversity changes over time are strongly linked to climate change The Late Ordovician mass extinction (~450 million years ago) =the second-largest mass extinction coincided with a short but intense ice age during which enormous glaciers grew and sea levels dropped it is believed that the majority of extinctions were caused by habitat loss due to falling sea levels and cooling of the tropical oceans

10 Current Activities Impacting land clearing Biodiversity

11 Current Activities Impacting land clearing Biodiversity More than half the native forest in Australia has been cleared in the last 220 years

12 Current Activities Impacting land clearing Biodiversity More than half the native forest in Australia has been cleared in the last 220 years for agriculture, mining, timber production and urban development

13 Current Activities Impacting land clearing Biodiversity More than half the native forest in Australia has been cleared in the last 220 years For agriculture, mining, timber production and urban development ~27,000 species lost from tropical rainforests each year (globally)

14 Current Activities Impacting Biodiversity Introduction of species 56 recognised vertebrate animal species introduced to Australia

15 Current Activities Impacting Biodiversity Introduction of species 56 recognised vertebrate animal species introduced to Australia Cane toad = for biological control WA Museum

16 Current Activities Impacting Biodiversity Introduction of species 56 recognised vertebrate animal species introduced to Australia Cane toad = for biological control Rabbit = for hunting Cat = for pets WA Museum

17 Current Activities Impacting Biodiversity Introduction of species 56 recognised vertebrate animal species introduced to Australia Cane toad = for biological control Rabbit = for hunting Cat = for pets WA Museum Issues include = competition for food and space with native species, predation and land degradation (e.g. brumby hooves)

18 Current Activities Impacting Biodiversity Soil degradation Salinity

19 Current Activities Impacting Biodiversity Soil degradation Salinity Increased fertiliser use (eutrophication)

20 Current Activities Impacting Biodiversity Soil degradation Salinity Increased fertiliser use (eutrophication) Impact on local weather (e.g. decreased rainfall)

21 Current Activities Impacting Biodiversity Soil degradation Salinity Increased fertiliser use (eutrophication) Impact on local weather (e.g. decreased rainfall) Increased run off and erosion

22 Human Impacts on Biomass Our main impact on biomass is in the destruction of vegetation/land clearing The loss at level one of producers provides an on-flow effect

23 The Holocene Event The concept that we are currently in the most damaging mass extinction event of all time Began ~11,500 years ago Two pulses First ~10,000 years ago end of the last glaciation event movement of human populations Second ~1950 onwards - mass deforestation & other human activities

24 Charles Darwin Reserve 2003 White Wells Station was acquired by Bush Heritage 93% of the native vegetation on the station had been cleared 68,000 hectares (450km from Perth) In South West Botanical Province International biodiversity hotspot 4% of Australia s land area Has 52% of threatened plant species 12.5% of the world s rare flora For more info visit

25 References Conservation of Australia s Biodiversity, Department of Sustainability, Environment, Water, Population and Communities, last updated 28 August 2012, accessed at on 15 October 2012 Cane Toad, Western Australian Museum, 2010, accessed at on 15 October Unless otherwise stated all information and graphics are from: Tompkins, D.E. (Ed.), 2010, Exploring Earth and Environmental Science Stages 1, 2 and 3, Earth Science Western Australia or ESWA photo/graphic library

26 Jim Ross, Mitsui E&P Australia and Wythenshawe