Dry forest & woodlands

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Unit 2, Outcome 1
DISCOVERING OUTDOOR ENVIRONMENTS
2.1.1
Types and characteristics of selected
outdoor environments
Australians are the custodians of some of the most diverse
ecosystems on the planet. Our continent is one of the
world’s 12 biologically ‘mega-diverse’ regions, with a high
proportion of endemic species — those that are found
nowhere else in the world. For example, 93% of our
marsupial species and 88% of our native rodents are
endemic.
Victoria’s land area supports a wider range of broad ecosystems
than any area of a similar size in Australia: Alpine, marine,
coastal, heathlands. wetlands, grasslands, forest and arid.
Each have specific features/characteristics that make them
unique and different from others.
These environments support at least 3140 native species of
vascular plants, 111 mammals, 447 birds, 46 freshwater and 600
marine fish, 133 reptiles, 33 amphibians and 750 mosses.
This richness — in the number of different ecosystems and
different species, and the genetic variety they exhibit — is what
we call biodiversity.
KEY CONCEPT
Victoria contains a variety of natural
environments that have evolved and developed
over millions of years.
KEY CONCEPT
The specific type of environment you find
yourself in in dependent on a number of factors.
These include:
Geology
Climate
Position & Aspect
GEOLOGY
The influence of Geology can be seen in an area by the type of
rock found there, the soil characteristics and drainage.
• Soil changes occur through the parent rock, the elements
(wind/rain/sun), living and decomposing plants, and
groundwater.
• The shape of the land (topography) is also important, such as
is found at the Cathedral Range (upswept rocks).
CLIMATE
• Annual rainfall, extremes in temperature, and average daylight
hours are examples of climatic factors that can affect a
landscape. HOW?
• Other aspects include wind patterns, evaporation, ground
temperature, frost frequency and snow cover.
• Australian rainfall is seasonal and erratic, producing extended
periods of drought.
POSITION & ASPECT
Geographic location is very important when determining the development of
environment types. In physical geography, aspect generally refers to the
horizontal direction to which a mountain slope faces.
Aspect can have a strong influence on temperature. This is
because aspect affects the angle of the sun rays when they
come in contact with the ground, and therefore affects the
concentration of the sun's rays hitting the Earth.
The aspect of a slope can make very significant influences on its
local climate. The sun's rays are in the west at the hottest time
of day in the afternoon, in most cases a west-facing slope will be
warmer than a sheltered east-facing slope
Example:
• In Australia, remnants of rainforest are almost always found
on east facing slopes which are protected from dry westerly
wind.
• In eastern Australia, southerly and easterly aspects receive:
- Lower radiation loads, resulting in reduced water-loss
- Are fire protected, thus permitting the survival of rainforest
species.
Factors affecting natural environments.
• Read pages 61 – 62
• Complete a table in your workbook like this:
• Summarise as many key points as you can from the text
which influence the characteristics of Australian outdoor
environments.
Factors affecting natural
environments:
GEOLOGY
CLIMATE
POSITION AND ASPECT
Environmental influences of each
factor
Different types of outdoor
environments.
Research and map – Activity 1
1. Work with a partner to create a poster depicting the
characteristics of a specific outdoor environment.
*See Mrs. G for a detail handout of the topic.
2. Present your poster to the class in pairs. Individuals will
be required to take notes for their - ‘Biodiversity table of
Victorian Ecosystems.
Activity 2
To expand your understanding of the different types of
outdoor ecosystem, use ‘Victoria’s Biodiversity – Our
living Wealth’ or ‘Viridians’ to complete an unfinished
sections of your ‘Biodiversity table of Victorian
Ecosystems.
http://www.nre.vic.gov.au/plntanml/biodiversity/wealth/cont
ents.htm
or
http://www.viridans.com/ECOVEG/
Activity 3
On a large map of Victoria, outline the main
environment types and their distribution.
Make sure you follow appropriate mapping
conventions (BOLTSS+D) where possible.
(Viridians website will be useful here)
Dry forest & woodlands
Dry forest & woodlands
 The Great Dividing Range forms a barrier across
Victoria.
 It protects many north-facing slopes from the cool/moist
winds sweeping from Bass Straight.
 This results in the northern foothills being relatively dry.
Different forest ecosystems include:
• Stringybark forests (these dominate the near-coastal
landscape east of Western Port)
• Red gum forests survive along major rivers in the north
of the State
• Box–Ironbark forests lie in a wide arc from west of
Stawell to east of Wangaratta
Box-Ironbark forest
Red-Gum Forest
Stringy Bark Forest
Dry forest & woodlands
• Most of the dry forest & woodlands that
would have been found are now gone due
to clearing.
• Dry forests and woodlands are biologically
diverse and support a variety of plants and
animals, included some vary rare flowers
and birds.
• Habitat modification, vegetation clearance,
weed invasion, feral predators and loss of
hollow-bearing trees are significant
concern.
Arid and semi-arid areas
Arid and semi-arid areas
• Approx. 4 million yrs ago, a vast inland sea covered what
we now call the Mallee and the north-western part of
Victoria. This has left this area with a legacy of sand and
shallow soils that cover the area today.
• The area is dominated by low Mallee scrub and small
eucalyptus that can withstand prolonged dry periods and
harsh conditions.
• The flora and fauna in this place is remarkably diverse –
this being an area that seems very lifeless.
Grasslands
Grasslands
• Prior to European settlers arriving in Victoria, extensive
grasslands covered the plains between the Murray
Valley and the Great Dividing Range
• Indigenous people had used fire in the past to maintain
the open nature of the landscape.
• These grasslands contain a variety of floral species,
kangaroo grass, wallaby and spear grass.
• This environment attracted Europeans for uses in cattle
grazing, cropping and pasturelands.
Grasslands
• As a result of these things listed, less than
1% of Victoria’s native grasslands remains
intact today. These areas are however in
very small areas and therefore face the
risk of weed invasion, salinity and urban
development.
Heathlands
• Heathlands are
found within Vic
from the Coast to
the mountains.
• Characteristically
a low and
shrubby
environment,
trees twisted by
the dry winds
they are typically
subjects to.
Heathlands
• Nutrient levels in the
soil are generally low,
and the soils are also
acidic. These areas
have a close
relationship with fire,
some plants needing
this to re-germinate.
• The grass tree is one
example.
(Xanthorrhoea
australias)
Heathlands
• These environments are dominated by
hard-leaved plants such as banksias,
bottlebrushes, tea trees and eucalypts.
• As their name suggest they are also
populated by a number of heaths.
Wet Forests and Rainforests
• Victoria’s wet forests
and rainforests are
found in southern,
central and northeast
regions of the state.
They include the
Otways, Wilson’s
Prom, and the Alps .
• The worlds largest
flowering plant (the
Mountain Ash) occurs
in these ecosystems.
Wet Forests and Rainforests
• Other plants/trees include manna gum,
messmate stringybark, mountain grey
gum, Blackwood, and various tree ferns.
• Several rare mammals including possums
and birds require hollow trees to nest and
habitat.
• Many forest plants have adapted well to
fire and can re-establish them afterwards,
however rainforest plants have not
adapted well and can reduce significantly
after a fire.
The Alps
The Alps (Alpine)
• The word ‘Alpine’ is often used to describe any
high mountain area. Theoretically, the term
refers to the area above a certain altitude where
there are no trees because of prolonged cold.
• Snow covered areas of Australia cover approx
0.15% of the country (11,700 square km’s).
• Mt Kosciusko is Australia’s highest peak (2228
m) and Mt Bogong is Victoria's highest (1986
meters).
The Alps (Alpine)
• Aust. Alps have eroded
over 500 million yrs,
unlike others around the
world. This has formed
rounded mountains and
plateaus.
• Sphagnum moss is a
very unique vegetation
that has adapted to suit
the Victorian Alps.
Bogong High Plains
The Coast
The Coast
• Victoria has over 2000 km of coastline
• It ranges from sheltered bays and inlets to rugged
eroded cliffs.
• The west coast is sometimes exposed to gale forced
winds that have contributed to the amazing scenery
along the Great Ocean Road.
• The coast is constantly changing due to the relentless
effects of the wind, rain and waves.
• Some factors that influence coastal ve
• getation are related to wind, salt and natural land
instability.
The Coast
• Dunes are held together by grasses and herbs, while salt
marsh and mangroves inhabit the mudflats.
• These plants play a crucial role in holding the subsoil
together in these environments.
• Birds are the most common types of fauna in this
environment, ranging from Fairy Penguins to a large
number of migratory birds from Siberia, Japan and the
North Pacific Ocean.
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