Transcript applying - MY PORTFOLIO

Fire is an environmental factor that can affect
Australian lifecycles. In a PowerPoint identify
why fire is so important to one Australian
ecosystem.
•Four things are important to our
Australian landscape these are fire,
water, air and sunshine
•Is vital in ancient traditions
•It benefits specific plants and
animals
•When everything is covered in ash,
a new life is beginning
•Plant materials break down into
micro-organisms over many years
•Nutrients are released after a fire
and growth follows
•Some plants need fire to introduce
reproduction
•Considered disastrous by many
•Natural occurrence
•Releases nutrients to the soil and
creates rich seedbeds for newly
dispersed seeds
•First rains brings landscape to life
•Cycle of growth, competition and
maturation starts all over again
•Fire has been used for years by
Aboriginals to manage the
country
•Long-term use has influenced the
evolution of plants and animals
•Many plants depend on fire for
survival
•Managed correctly it is good for
the country but managed
incorrectly it does large damage
•Fire affects everything from
plants to animals
•An example of a healthy fire cycle
is
Unburnt, old
Spinifex
Freshly burnt
growing back
country
0-6 months
after managed
burn
five years after
burn
one year after
managed burn
You’ve just seen an general overview as to why fire is an important factor to
life cycles in the Australian ecosystem, now let’s take a look at one
ecosystem in particular – The Australian Eucalyptus
Fires play a natural and useful role in the life-cycle of a forest and its
ecosystem. But fire can also have a devastating long-term effect on
ecosystems that are not adapted to such patterns of burning but
important to remember that fire is a natural part of the environment and
not only are many of the species fire resistant, but some actually depend
on fire to trigger new growth and to germinate seeds.
Eucalyptus trees have dotted the Australian landscape for millions of
years, and today they are probably the most common trees on the
continent. Eucalyptus are able to survive poor soil, dry spells, and fire
and are hardy enough to have spread throughout much of the land and
take a central place in the lives of the forest's wildlife.
Eucalyptus oil catches fire very easily, and bush fires can travel quickly
through the oil-rich air of the tree crowns. The dead bark and fallen
branches are also flammable. Eucalypts are well adapted for periodic
fires - in fact most species are dependent on them for spread and
regeneration. They do this in several ways: by sprouting from
underground tubers, hidden buds under their bark and from seeds
sprouting in the ashes after the fire has opened them.
As fire sweeps through a eucalyptus forest, destroying everything in
sight , the area appears to be devastated, Fires take warm air up into the
tops of the trees, which dries the cones and makes them split, allowing
the seeds to pop out. Fire also clears the undergrowth allowing the
seeds to germinate. To allow these processes to continue, the
authorities started creating controlled fires and allowing natural fires to
burn.
The eucalyptus trees will recover quickly however, and even thrive.
Eucalyptus leaves contain oils that can actually fuel an intense fire, but
the tree's thick bark protects its core from damage. Eucalypts grow
back quickly after fire because they are so well adapted to fire that a
blaze actually causes them to flourish. Soon after a fire dies out,
chemical changes triggered by the flames' heat cause new buds to
shoot out of the trees. The fire's hot winds can also help distribute
eucalyptus seeds.
Most dry eucalypt species have evolved under a variety of conditions
in response to soils with low nutrient levels, periodic droughts and the
prevalence of fire. They germinate readily following a fire while wet
eucalypt forests species and rainforest species are killed by fires. Wet
eucalypt forests tend to evolve where fire disturbance is infrequent and
rainfall is high.
Eucalyptus has adapted to the harsh Australian environment. It has a number of
features including a very deep root system that can store water and act as an
emergency store of water in dry seasons.
Eucalypts have a thick waxy coating on the leaves to protect them from water
loss. leaves hang vertically, rather than horizontally, so that the surface area
exposed to direct sunlight is reduced and therefore water loss due to
evaporation is also reduced.
Many Eucalypts have a very thick and hard coating of bark on the lower truck –
a sock – which protects the trunk from fire damage. Eucalyptus oil in the leaves
has a taste that is unpleasant to most predators. However, interestingly the Koala
has also made some adaptations, and is able to eat huge amounts of Eucalyptus
leaves.
All eucalypts are evergreen but shed part of their canopy to reduce their water
need in high heat. These changes and adaptations occurred over thousands of
years as the climatic conditions gradually changed. Each new generation –
derived from seeds that germinate and grow to maturity and then in term
reproduce themselves. – has the potential to show some new changes. However,
it takes generations and generations to see significant change.
Fire in the cycle of life: An ideas and resources kit to interpret fire in the
Australian Alps, 2003, Australian Alps Liaison Committee
Grampians National Park Fire ecology - an overview, 2004, Grampian National
Park Notes
The Fire Book, 2005, Tangentyere Landcare
Eucalypt Forests: Parks and wildlife service Tasmania, 2014, Retrieved from
www.parks.tas.gov.au 23/9/14
Eucalypt Forests of Tasmania: Parks and wildlife service Tasmania, 2014, Retrieved
from www.parks.tas.gov.au 23/9/14
Eucalypts, Retrieved from www. australia.gov.au 23/9/14
Rohr. I., 2006, Go Facts: Fire and Drought. Australia, Blake Publishing
McGhee, Margaret., 2004, Australian Focus on issues: Bushfires, Australia,Watts
Publishing