VCE Biology Unit 2 Area of Study 01 Adaptations of Organisms 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, , and 2009 Department of Sustainability and Environment “Fire and Other Emergencies” hilddocs/-D79E4FB0C437E1B6CA256DA60008B9EF?openhttp:// hilddocs/-D79E4FB0C437E1B6CA256DA60008B9EF?open Most Australian plants are adapted to fire.
Bushfire, La Trobe Valley, February 2009
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
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
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
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
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