Download VCE Biology Unit 2 Area of Study 01 Adaptations of Organisms

VCE Biology Unit 2
Area of Study 01
Adaptations of Organisms
Chapter 13.4
Surviving a major disturbance
Chapter 13.4 Surviving a major disturbance
Fire
• Victoria – major fires in 1851, 1898, 1905, 1906, 1912,
1914, 1919, 1926, 1932, 1939, 1942, 1943, 1944, 1952,
1962, 1965, 1968, 1969, 1972, 1977, 1980, 1983, 1985,
1997, 1998, 2002, 2003, 2005-2006, 2006-2007 and 2009
Department of Sustainability and Environment “Fire and
Other
Emergencies”http://www.dse.vic.gov.au/dse/nrenfoe.nsf/c
hilddocs/-D79E4FB0C437E1B6CA256DA60008B9EF?open
• Most Australian plants are adapted to fire.
Bushfire, La Trobe Valley, February 2009
Chapter 13.4 Surviving a major disturbance
Epicormic buds of eucalypts
• Flammable oils in leaves result in rapid hot fire
• Destroys crowns of trees but only chars the trunks
• Bark is good insulator against heat
• Bark protects underlying cambium layer
• Cambium layer produces regenerative growth of bark
and woody tissue
Chapter 13.4 Surviving a major disturbance
Epicormic buds of eucalypts (continued)
• Epicormic buds, which lie under the bark of stems
and roots, allow sprouting and re-growth
• For plant stem to survive, both cambium layer
and epicormic buds must survive
• Epicormic buds are kept dormant by growth
inhibitors produced by the crown of the tree
Lady Talbot Drive, Marysville, August 2008
Lady Talbot Drive, Marysville, February 2009
Lady Talbot Drive. Marysville. April 2010
Lady Talbot Drive, Marysville, April 2010
Chapter 13.4 Surviving a major disturbance
Lignotubers – underground protection
• When all above ground parts of tree has been
destroyed, plants that have lignotubers,
rhizomes (underground stems) or root suckers
can regenerate from subterranean buds
• A lignotuber is a swelling at the base of the
stem where dormant buds lie.
Lignotubers
Chapter 13.4 Surviving a major disturbance
Tough wattle seeds
• In Australian forests, Acacia species make up
most of the understorey
• Acacia seeds have hard outer seed coats and
can survive high temperatures and require
heat to germinate.
Acacia seeds
Acacia seedlings after fire
Chapter 13.4 Surviving a major disturbance
How do animals live with fire?
• Small animals killed by fire, but fire burns in a mosaic
pattern and unburnt areas are left.
• Predator birds patrol in front of fire front to catch prey
• Butcherbirds eat animals exposed by lack of undergrowth
• Parrots eat seeds and young plants in the regenerating
forest
• Some animals live underground to escape fire and
predators
Tarra Bulga National Park, December 2009
Just north of Tarra Bulga National Park, December 2009
Just north of Tarra Bulga National Park, December 2009