Deserts year 10

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• Watch an Attenborough documentary. If you have
Netflix, they are on that. This is just a link for
those who don’t have Netflix. Its not the best
quality.
https://www.youtube.com/watch?v=RD56Aj0YW
XI
• This one is about Arabia, but not Attenborough.
https://www.youtube.com/watch?v=F83XAKUN9
54
Deserts year 10
http://www.ga.gov.au/scient
ific-topics/national-locationinformation/landforms/dese
rts
Hot and temperate (cold) deserts
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Word definitons for HSC
Learn
Practice
Discriminate between
Follow : Mindfullness in answering/ exam
technique!
In terms of global wind patterns,
typical deserts are…
• Located mainly within Southeastern and
Northeastern Trade wind belts.
• Due to the direction of wind movement in these
regions, the land receives dry air because the
moisture is removed before the air gets to the
region.
• Most deserts are formed because the moisture is
removed from the air over the tropical rainforests
before travelling to these regions. Deserts can
also be created when the air they receive passes
over a mountain range first. When the air rises to
move over the mountain range, it cools, and the
moisture in the air is lost as rain. As a result, when
the air gets over the mountain range, it is very
dry.
Climate
• What does it mean?
• Definition
• Esp
• Precip
• temp
Temperature – another defining and
unique characteristic
• Most are warmer in the day than at night, and the different is quite
drastic. Average daytime temperature 40 degrees C, while at night
average temps of between 5 and below zero degrees C.
• Large diurnal temperature difference is due to low amounts of
moisture in the deserts air. LARGE DIURNAL RANGE
• Normally moisture in the air absorbs and retains heat energy in high
INSOLATION (day) and helps to regulate temperature by releasing
this back into the air when the INSOLATION decreases (night).
• As very little moisture in the air, there is nothing to absorb and
retain heat energy transferred during the day by the sun
INSOLATION.
• As a result, when the sun sets, the heat energy escapes and the
temperature drops.
• Desert environments
are so dry that they
support only
extremely sparse
vegetation; trees are
usually absent and,
under normal climatic
conditions, shrubs or
herbaceous plants
provide only very
incomplete ground
cover.
Extreme aridity renders some deserts virtually devoid of plants;
however, this barrenness is believed to be due in part to the
effects of human disturbance, such as heavy grazing of cattle, on
an already stressed environment.
Environment
• Deserts are varied and variable environments
and it is impossible to arrive at a concise
definition that satisfies every case.
• However, their most fundamental
characteristic is a shortage of available
moisture for plants, resulting from an
imbalance between precipitation and
evapotranspiration.
This situation is exacerbated by considerable variability in the
timing of rainfall, low atmospheric humidity, high daytime
temperatures, and winds.
Average annual precipitation ranges
• From almost zero in some South American coastal
deserts and Libyan deserts to about 600mm in deserts
in Madagascar, although most recognised deserts have
an annual rainfall of below 500mm.
• Some authorities consider 250mm the upper limit for
true (arid) deserts,
• describing places with 250 – 500mm as semiarid
deserts.
• Regions this dry are barely arable and contribute to
human food production only by providing grazing lands
for livestock.
Latitudes and desert locations clip
• INSOLATION and thermal gradient explained
Global-circulation-patterns
Pressure and weather
https://www.youtube.com/watch?v=4ozwCtUuU_s
More detailed video
• details video on global atmospheric
circulation, pressure and weather
• medium detail video
3 cells
• Hadley cell
• The largest cells extend from the equator to between 30 and 40
degrees north and south, and are named Hadley cells, after English
meteorologist George Hadley.
• Within the Hadley cells, the trade winds blow towards the equator,
then ascend near the equator as a broken line of thunderstorms,
which forms the Inter-Tropical-Convergence Zone (ITCZ). From the
tops of these storms, the air flows towards higher latitudes, where
it sinks to produce high-pressure regions over the subtropical
oceans and the world's hot deserts, such as the Sahara desert in
North Africa.
• Ferral
• and Polar
Ferral cell Just FYI
• In the middle cells, which are known as the Ferrel cells, air
converges at low altitudes to ascend along the boundaries between
cool polar air and the warm subtropical air that generally occurs
between 60 and 70 degrees north and south. This often occurs
around the latitude of the UK which gives us our unsettled weather.
The circulation within the Ferrel cell is complicated by a return flow
of air at high altitudes towards the tropics, where it joins sinking air
from the Hadley cell.
• The Ferrel cell moves in the opposite direction to the two other
cells (Hadley cell and Polar cell) and acts rather like a gear. In this
cell the surface wind would flow from a southerly direction in the
northern hemisphere. However, the spin of the Earth induces an
apparent motion to the right in the northern hemisphere and left in
the southern hemisphere. This deflection is caused by the Coriolis
effect and leads to the prevailing westerly and south-westerly winds
often experienced over the UK.
Polar cell just FYI
• The smallest and weakest cells are the Polar
cells, which extend from between 60 and 70
degrees north and south, to the poles. Air in
these cells sinks over the highest latitudes and
flows out towards the lower latitudes at the
surface.
Global atmospheric circulation
patterns – Hot deserts and the
Hadley cell
• The arid conditions of the major deserts result from their position in
subtropical regions to either side of the equatorial belt. The
atmospheric circulation pattern known as the Hadley Cell plays an
important role in desert climate. In areas close to the Equator, where
the amount of incoming solar energy per unit surface area
(INSOLATION) is greatest, air near the ground is heated, then rises,
expands, and cools.
• This process leads to the condensation of moisture and to
precipitation. At high levels in the atmosphere, the risen air moves
away from the equatorial region to descend eventually in the
subtropics as it cools; it moves back toward the Equator at low
altitudes, completing the Hadley cell circulation pattern.
• The air descending over the subtropics has already lost most of its
moisture as rain formed during its previous ascent near the Equator.
As it descends, it becomes compressed and warmer, its relative
humidity falling further.
• Hot deserts occur in those regions to the North and
South of the equatorial belt that lie beneath these
descending, dry air masses (i.e 30 degrees N and S).
• This pattern may be interrupted where local
precipitation is increased, especially on the east side
of continents where winds blow onshore, carrying
moisture picked up over the ocean.
• Conversely, deserts may be found elsewhere, as in the
lee of mountain ranges, where air is forced to rise,
cool, and lose moisture as rain falling on the windward
slopes.
Precipitation - Rainfall in deserts
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Usually meagre, in some cases several years may pass without rain, e.g. Cochones
in Chile received no rain at all in 45 consecutive years between 1919 and 1964.
Usually, however, rain falls in deserts for at least a few days each year – typically 15
– 20 days.
When precipitation occurs it may be very heavy for short periods. FLASH FLOODS
E.g. 14mm fell at Mash‘abe Sade in Israel in only 7 minutes on October 5th 1979.
In southwestern Madagascar the entire annual rainfall commonly occurs as heavy
showers falling within a single month.
Such rainfall usually occurs only over small areas and results from local convection
cells, with more widespread frontal rain being restricted to the southern and
northern fringes of deserts. LOCALISED FLASH FLOODING
In some local desert showers, the rain falling from clouds evaporates before it hits
the ground.
Regions near the equatorial margins of hot deserts receive most of their rain in
summer – June to August in the Northern Hemisphere and December to February
in the Southern Hemisphere – while those near the temperate (cold) margins
receive most of their rainfall in winter.
Rain is particularly erratic and equally unlikely to occur in all seasons in
intermediate regions.
Complete climate graph work
• Find or draw a climate graph of a city in your
chosen desert. Be able to describe this
climate. Look at
http://www.bbc.co.uk/schools/gcsebitesize/ge
ography/weather_climate/climate_rev5.shtml
to help.
Some deserts near coasts
• E.g. Namib Desert in southwestern of Africa and
those of the west coasts of the Americas in
California and Peru, fog is an important source of
the moisture that is otherwise scarce. Moisture
droplets settle from the fog onto plants and then
may drip onto the soil or be absorbed directly by
plant shoots. Dew may also be significant,
although not in deserts in from the central parts
of continents where atmospheric humidity is
consistently very low.
Atmospheric humidity
• In most deserts it is usually too low to permit
the formation of fog or dew to any significant
extent.
• Potential evaporation rates (rate if water were
continually present) are correspondingly high,
typically 2,500 to 3,500mm per year, as much
as 4,262 mm potential evaporation per year
recorded in Death Valley in California.
• Find some examples of desert landforms in
your chosen case study (hint: its not just sand
dunes, they also have hobgoblins!!). How have
these landforms been created? Look at the
role of wind and water as agents of erosion
and temperature changes along with wind as
an agent of weathering. Look also at
deposition.
Winds and landforms
• Not unusually strong or frequent in comparison with adjacent
environments, but the general lack of vegetation exacerbates the
effect of wind at ground level. Winds can induce the erosion of fine
materials and the evaporation of moisture and thereby help
determine which plants survive in the desert.
• Rain falling on hot rocks can cause them to shatter and the resulting
fragments and rubble strewn over the desert floor is further eroded
by the wind. This picks up particles of sand and dust and wafts
them aloft in sand or dust storms.
• Wind-blown sand grains striking any solid object in their path can
abrade the surface. Rocks are smoothed down, and the wind sorts
sand into uniform deposits. The grains end up as level sheets of
sand or piled up high in billowing sand dunes.
• Other deserts are flat, stony plains where all the fine material has
been blown away and the surface consists of a mosaic of smooth
stones. These areas are known as desert pavements and little
further erosion takes place.
• Hot deserts as their name implies experience very high
temperatures by day especially in Summer.
• Temperate or cold deserts occur in temperate regions
at higher latitudes and therefore colder temperatures
than those at which hot deserts are found. These dry
environments are caused by either remoteness from
the coast which results in a low atmospheric humidity
from a lack of onshore winds, or the presence of high
mountains separating the desert from the coast.
• The largest area of temperate desert lies in Central
Asia, with smaller areas in western North America,
southeastern South America and southern Australia.
• While they experience lower temperatures than the
more typical hot deserts, temperate deserts are similar
in aridity and consequent environmental features
including landforms and soils.
Landforms
• Other desert features include rock outcrops, exposed bedrock and clays
once deposited by flowing water. Temporary lakes form and salt pans may
be left when the water evaporates. There may be underground sources of
water in the form of springs and seepages from aquifers. Where these
occur oases can occur.
• The peculiar climatic environment of the deserts has favoured the
development of certain characteristic landforms. Stony plains called regs
or gibber plains are widespread, their surface covered by desert pavement
consisting of coarse gravel and stones coated with a patina of dark “desert
varnish” (a glossy dark surface cover consisting of oxides of iron). Rocky,
boulder-strewn plateaus cut by dry, usually steep-sided valleys called
wadis are also found in deserts in many parts of the world.
• The local topographic and microclimatic variations produced by this
rugged surface, and the opportunities for runoff – and in a few places
surface accumulation- of rainwater, are important in providing localised
habitats for plants and animals. Large areas of loose, mobile sand provide
the harshest and poorest of the major desert habitat types.
Soils
• Desert soils are mainly immature, weakly developed in
terms of their soil profiles, and mostly alkaline. Sands,
sandy or gravelly loams, shallow stony soils, and
alluvium (material deposited by rivers and streams)
and scree-derived deposits (rocky material at the base
of cliffs) predominate. Although almost always dry,
these soils may support well-developed microbial
communities, particularly in association with roots.
Domestic animals, however can have a deleterious
impact by trampling and compacting soil; this activity
can reduce the infiltration of water and damage
vegetation, leading to erosion and redistribution of soil
materials.
Biological Productivity
• In the highly stressful desert environment, productivity is generally very
low; however, it is also highly variable from time to time and from place to
place.
• Temporal variations are caused by the occasional input of moisture; this
allows the vegetation to grow for only a short period before arid
conditions resume. Spatial variations are due in part to the structural
patchiness of the vegetation itself, as surface soil beneath shrubs is several
times more fertile than it is between shrubs.
• Shrub roots contribute to this process by retrieving nutrients from the
deep soil and depositing them in the litter on the soil surface beneath the
shrub canopy.
• Windblown litter that accumulates around shrubs and the microbial flora
found in soil shaded by the shrub canopy also creates patchy, fertile areas.
• Because human disturbance of desert vegetation commonly involves the
partial or total removal of the shrub cover, the impact of human
disturbance on these ecosystems is significant.
• Draw a simplified food chain/food web in your
chosen desert. An example from the Sahara is
here:
https://sites.google.com/site/charlessaharade
sert/food-web-and-food-chain
• Outline how plants and animals in your
chosen case study are adapted to this
environment.
Flora
Fauna
Deserts
• Definition: any large, extremely dry area of land with sparse vegetation.
One of the Earth’s major ecosystems, supporting a community of
distinctive plants and animals specially adapted to the harsh environment.
( Britannica online encyclopedia).
• According to some definitions, any environment that is completely free of
plants is considered to be a desert, including regions too cold to support
vegetation – i.e frigid deserts.
• Other definitions use the term desert to apply only to hot and
temperate(cold) deserts, a restriction followed from here.
• Precipitation definition/criteria of deserts:
• True/Arid: receive less than 250mm precipitation per year
• Semi Arid: receives between 250 and 500 mm precipitation per year.
• A desert is a barren area of landscape where little precipitation occurs and
consequently living conditions are hostile for plant and animal life. The
lack of vegetation exposes the unprotected surface of the ground to the
processes of denudation. About 1/3rd of the World’s land surface is arid or
semi-arid. This includes much of the polar or cold deserts.
• Deserts can be classified by the amount of precipitation that falls, by the
temperature that prevails, by the causes of desertification or by their
geographical locations.
Deserts biomes can be classified
according to several characteristics.
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There are 4 major types:
Hot and Dry
Semi Arid
Coastal
Cold/Temperate
Precipitation
• Although most of us think of deserts as places
that do not get much rain the precipitation
received in deserts can be in the form of
either rain or snow.
• 1 classification of deserts uses precipitation:
• Deserts that receive their precipitation as rain
are called hot deserts and those that receive
snow are called cold (temperate) deserts.
Sub-classified as: Hot and Cold
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Hot generally located along the tropics (and on Westward coasts)
Hot and Dry deserts
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Australian
Ethiopian (Africa)
Southern Asian Realm,
Neotropical (South and Central America)
4 major North American deserts of this type
are:
• Chihuahuan, Sonoran, Mojave and Great
Basin.
Hot and Dry deserts
• Seasons - Generally warm throughout the year and very hot in the
summer. Winters usually bring little rainfall.
• Atmospheric humidity is so low little blocking of the Sun’s rays.
• Desert surfaces receive a little more than TWICE the INSOLATION
received by humid regions and lose twice as much at night.
• Soil surface temperatures can rise even beyond that of the air with
values as high as 78 degrees C recorded in the Sahara.
• Night temperatures fall dramatically because the same lack of cloud
cover that admits high levels of INSOLATION in the day also allows
rapid loss of energy through longwave radiation at night.
• Diurnal temperature range – Many mean average temperatures
range from 20 – 25 degrees C. Minimum temp sometimes drop to 18 degrees C. Extreme maximum ranges from 43.5 – 49 degrees C.
Hot and dry deserts
• Rainfall – usually very low and/or concentrated in
short bursts between long rainless periods.
Evaporation rates regularly exceed rainfall rates.
Sometimes rain starts falling and evaporates
before reaching the ground!
• Rainfall is lowest on the Atacama Desert of Chile,
where it averages less than 15mm. Some years
are even rainless. Inland Sahara also receives less
than 15mm/yr.
Hot and dry deserts
• Soils – coarse-textured, shallow, rocky or
gravely with good drainage and have no
subsurface water.
• They are coarse because there is less chemical
weathering.
• The finer dust and sand particles are blown
everywhere, leaving heavier pieces behind.
Hot and dry deserts
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Canopy – in most deserts is rare.
Plants – mainly ground- hugging shrubs and short woody trees.
Leaves are “replete” (fully supported with nutrients) with water conserving
characteristics.
Tend to be small, thick and covered with a thick (waxy) cuticle.
In cacti – leaves are much-reduced to spines and photosynthetic activity is
restricted to stems.
Some plants
Including: yuccas, ocotillo, turpentine bush, prickly pears, false mesquite,
sotol, ephedras, agaves and brittlebrush.
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open their stomata for gas exchange only at night when evaporation rates are
lowest.
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Animals
Include small nocturnal carnivores. Dominant animals are burrowers and kangaroo
rats. There are also insects, arachnids, retiles and birds.
The animals stay inactive in protected hideaways during the hot day and come out
to forage at dusk, dawn or at night, when the desert is cooler.
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Australian Deserts are subtropical which means
they are in the same category as the Sahara and
Kalahari Deserts in Africa and the Mojave desert
in the USA. Hot and dry.
• Not all desert areas are expanses of dry sand. In
Australia, water is available if you know where to
look for it. The semi-arid grasslands. Or
savannahs, support Australia’s beef cattle
industry. The Savannahs merge into the dry
desert and the boarders of savannah regions can
easily become very arid if the weather changes
and there is not enough rainfall in any one year.
Water in the Australian Deserts
• Although Australia’s deserts are dry, sandy
places, they still have some sources of water.
In temperate regions, the water cycle brings
rain to the land. In Australia’s deserts, rain
rarely falls.
Any water that evaporates is carried away to
other areas. When this moisture in the air hits
an area of cold air, water condenses forming
clouds and precipitation.
This precipitation falls into the ocean or on
land, where rivers carry it back into the
deserts.
The cycle then continues as water in the
desert evaporates in the intense heat.
Underground water
• Some water exists as underground reserves and comes
to the surface as springs. Over time, mineral deposits
in the water can cause a mound to build up around the
spring.
• These mound springs were very important to the
traditional owners of the land, wildlife and livestock.
• Water from the mound flows around it creating a pool,
which can be a permanent oasis in the desert.
• The Dalhousie Springs are a large and well known
mound spring in the Australian desert.
The Great Artesian Basin – a
freshwater source
• The GAB lies beneath more than 20% of
Australia, much of it beneath desert areas.
• The underground water reserve is a mixture of
ancient freshwater as well as top-up water
that seeps into it from areas where rainfall is
high, such as along the Great Dividing Range.
• The GAB is under threat from overuse and
water flows have declined since people began
drawing from it for livestock and mining.
Rivers and Creeks
• When heavy rain falls in areas outside the
deserts, water flows along rivers and creeks that
are normally dry, eventually providing water to
arid regions. The monsoon in northern Australia
sends water into the inland deserts in this way.
• Many desert plants and animals have developed
adaptations that take advantage of these
temporary sources of ewater which dry up
quickly.
Salt Lakes
• Salt lakes exist throughout Australia’s deserts. They are low-lying
areas into which creeks drain when there is rain. The extreme heat
evaporates all the water leaving only a salty crystalline covering on
the dry lakebed.
• When there is water in these lakes life flourishes many birds
migrate, fish and frogs appear and plants bloom quickly, producing
large quantities of seeds.
• Budgerigars fly long distances to feed on the seeds of deserts plants
after the rains.
• Shrimp and fish produce eggs, which can survive long periods
buried in the desert until the rain returns. Then they grow quickly
and breed before it dries again.
• Kati Thanda – Lake Eyre in South Australia is a salt lake that
periodically becomes the largest freshwater lake in Australia WHEN
it fills with rain water.
Dam – Ord River Irrigation Scheme
• This massive irrigation scheme in the north of
Western Australia involved damming the River
Ord.
• Lake Argyle was produced as a result and it is
now one of the largest artificial lakes in the
world, holding more water than Sydney
Harbour.
• The scattered settlements in the deserts and
savannahs resulted in these areas being one
of the most untouched environments in
Australia. However, feral animals, mining
tourism and defence force activities have now
caused changes to parts of these desert
ecosystems.
Afghan cameleers
• Afghan cameleers provided a transport service
and the supply of goods to settlers across the
deserts during the 180’s. The Afghans
accompanied many of the early explorers, who
could not have succeeded without their
assistance.
• A tax was introduced on camels in and as a result
many were set free rather than be slaughtered.
As a direct result Australia now has a feral camel
problem.
Economic Utility of Australia’s deserts
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Tourism
Mining
Defence Force Areas
Art
Cattle – Canning Stock Route
Tourism
• Australia’s deserts attract tourists who want to
experience the open spaces and the bright
night skies, unaffected by the light pollution of
the World’s cities.
• Many desert locations are on traditional
Aboriginal lands.
• Tourists may need a permit to visit them and
areas of spiritual significance SHOULD be
shown respect. (Uluru)
Mining
• Mining in the deserts provides employment
and therefore contributes to the economy.
• The desert flora and fauna and the balance
between them are fragile and can be easily
destroyed.
• Balance is needed between preservation of
flora and fauna, and the mining of resources
for economic benefit.
Defence Force Areas
• Australia’s deserts are the location of a number of military
and security facilities.
• Defence Facility Pine Gap – NT
- A satellite tracking and communications Centre
• Maralinga – SA
- The site of ATOMIC BOMB testing from 1955 – 1963.
• Woomera Prohibited Area – SA
- A rocket testing establishment.
Art
• Art in Australia often looks to the deserts for
inspiration.
• Famous artists such as Russell Drysdale, Albert
Namatjira and Sidney Nolan used the desert
landscapes in their paintings.
• The Papunya Tula art of the Aboriginal desert
painters is sought by art collectors around
Australia and the world.
Cattle Industry
• Australia has a thriving beef cattle industry in the
savannahs. Although the restricted water supply and
the saltbush that the cattle eat both make the
savannah unsuitable for raising dairy cattle, farmers
can successfully raise beef cattle.
• They make up for sparse vegetation by having
extremely large areas on which the cattle can graze.
• Early settlers believed the hot, dry conditions would
result in fewer tick infestations than wetter climates.
• Later they introduced other breeds like the Brahman
and crossbred to create new drought tolerant cattle
subspecies, such as Drought-Master cattle.
Canning Stock Route
• 1 of the world’s largest stock routes, covering
1,800km across the western Australian desert.
• Crossing the Gibson Desert, the Little Sandy
Desert and the Great Sandy Desert.
• Alfred Canning first surveyed it in 1906, his
aim to produce a route for droving cattle from
the Kimberley region in the north down to
Kalgoorlie where they would be sold.
Canning Stock Route – Water and War
• The provision of water along this route was
paramount.
• It relied on the knowledge of the First People of
Australia who had been using these water
sources for thousands of years.
• However this resulted in bloody, violent conflict
and the ruination of many water holes.
• It was never really successful and the land it
traverses is now largely returned to it’s original
owners.
• It is now a popular tourist route.
Feral animals
• Australia’s feral animals are descended from
domesticated animals that have either escaped
or been released into the wild.
• Examples include: Camels, horses, donkeys, wild
pigs, goats, cats, dogs and rabbits.
• They are all very destructive.
• They ruin water holes, overgraze, kill small
animals.
• They provide no contribution to the natural
desert ecology.
Threats to Australian desert
biodiversity
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Muddying and pollution of water sources.
Climate Change
Mining, tourism and the grazing of livestock.
Weeds and feral animals.
Specific Australia Desert economies
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Great Victorian Desert
Great Sandy Desert
Tanami Desert
Simpson Desert
Gibson Desert
Little Sandy Desert
Strzelecki Desert
Sturt Stony Desert
Tirari Desert
Pedirka Desert
Great Victorian Desert
Traditional Owners: Maralinga Tjarutja people.
Location: south of WA extending into SA
• Largest desert in Au.
• Includes: stony gibber plains, salt lakes and
red sand hills.
• Named by Earnest Giles in 1875. The first
European to cross it.
• Nuclear weapons were tested at Maralinga in
the 1950s. Some traditional owners were
exposed to nuclear fallout and the effects of
contamination of the environment.
Great Victorian Desert
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Flora and Fauna:
Princess parrot
Major Mitchell cockatoo
Mallee fowl
Woma python
Southern marsupial mole
Gould’s goanna
Australian bustard? Buzzard?
Scarlet-chested parrot
Spinifex
Saltbush
Great Victorian Desert
• Economic Activities
• Tourism
• Visitors must obtain permits for some areas. No facilities so all fuel, food
and water have to be carried.
• Mining
• Surface mining for gold occurs on the edge of the desert, reserves of iron
ore and other minerals are as yet unmined.
• The GVD Biodiversity Trust was set up under the mining requirements
established by the WA government. The Trust’s role is to investigate
conservation and biodiversity in relation to mining activities.
• Livestock grazing
• There has never been large scale grazing of livestock in the GVD because
of this there are very few weeds to compete with native vegetation.
Great Sandy Desert
Traditional Owners: Martu and Pintupi people.
Location: north of WA extends into NT.
Westerly limit Indian Ocean at 80 mile beach on WA coast.
• The GSD includes stony gibber plains, salt lakes and red sand dunes.
• Also regions of savannah grassland and a few gum trees.
• First European settler to cross the GSD was Peter Warburton in 1874. An
Aboriginal man called Charley assisted him. Warburton attributed his
survival in this crossing to Charley’s skill and knowledge.
• A Martu couple, Warri and Yatungka, may have been the last Aboriginal
people who had never met Europeans. When they came out of the GSD in
1974, their story was widespread across AU and created great interest.
• 2 main population settlements: Telfer, a mining town, and Yulara, which is
the service centre for the Uluru-Kata National Park.
• The Wolfe Creek meteorite crater is ion the north of the GSD. It is 300,000
yrs old and it weighed about 50,000 tonnes.
• The Djaru people call the crater Kandimalal.
Great Sandy Desert
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Flora and Fauna:
Marsupial mole
Rufous hare-wallaby
Bilby
Spinifex
Great Sandy Desert
• Economic Activities
• Tourism
• Uluru-Kata National Park is in the south-east of this desert. The tourist
facilities are confined as much as possible to specific areas. People
travelling through the desert are encouraged to stick to the tracks to avoid
damaging the environment.
• Mining
• Gold and copper has been mined in the GSD and there are uranium
reserves. As yet untouched!
• Livestock Grazing
• Cattle are grazed in the western part of this desert on about 7% of the
total GSD area.
• Arts
• The Aboriginal people of this area have developed a thriving arts
movement.
Tanami Desert
Traditional Owners: Kutatja and Warlpiri people.
Location: Kimberley region in WA to near Alice Springs in the NT.
• The Tanami desert has mostly flat, red sand plains.
• Main townships are the communities of Yuendumu, Nyirrpi,
Willowra and Lajamanu.
• Histor of violent clashes when the traditional owners
opposed the use of their land for grazing livestock and the
associated hostile take over of their traditional watering
holes.
• In 1928, the Coniston Massacre occurred after an aboriginal
man killed a white worker on one of the grazing properties.
• In reprisal, groups including the police, white settlers and
some Aboriginal trackers took weeks to hunt down and kill
about 60 Warlpiri men, women and children.
Tanami Desert
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Flora and Fauna:
Western chestnut mouse
Little native mouse
Grey falcon
Australian painted snipe
Freckled duck
Western hare-wallaby
Spinifex
Native rock fig
Tanami Desert
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Economic Activities
Tourism
The Tanami Track crosses this desert and gives tourists a route they can follow to see its isolated
beauty. Unlike the larger deserts Tanami does have some tourist stops where limited facilities and
fuel are available. The Stuart Highway also crosses parts of the Tanami Desert.
Mining
Gold is mined in underground operations in the TD. The mining operators monitor water quality,
noise, dust emissions and the presence in environment of cyanide, which is used to extract gold
from the ore!
Livestock grazing
There are a few pastoral areas. The lack of water has kept 75% of the Tanami Desert free from the
effects of livestock on the natural ecosystem.
Newhaven Wildlife Sanctuary
Covering 262,000 hectares
1 of Australia’s largest non-government areas for protection of wildlife. It is a bird-watching
destination home to 170 species of birds.
Involves Warlpiri people in its management.
Karlu Karlu/ Devils Marbles
Located on the Stuart Highway on the edge of the Tanami Desert, these rock formations have been
formed by erosion. The tip of a large mass of underground granite. A sacred site for the Kaytete,
Warumungu, Warlpiri and Alyawarra traditional owners. Visitors are asked not to climb them.
Animals include the Fairy Martins, little birds that build mud nests hanging from the underside of
the boulders, keeping their nestlings in the shade. Also finches, black-headed goanana and large
sand goannas that live in the micro-climate created by the huge balancing boulders.
Simpson Desert
Traditional Owners: Wangkangurru, Yarliyandi and Arrernte people.
Location: 3 states: SA, Queensland and NT
• Salt lakes and grass plains.
• Parallel, red sand dunes cover 100’s of km. Tallest sand dune in the
Simpson Desert is 40 m high and is called Nappanerica or Big Red.
• Stationary dunes, unlike in some deserts, mostly anchored by vegetation.
• Apart from the few permanent water holes, it receives a small amount of
rain causing sudden brief explosions of plant growth.
• Great Artesian Basin lies under the Simpson Desert.
• Surface is dry, but GAB surfaces in springs or from bores.
• First European to see it was Charles Sturt in 1845.
• Knowledge of water hole was vital to the Aboriginal survival and it was
passed on through art and in ceremonies.
• They actively dug and maintained the springs over many generations.
• Pastoralists were desperate to find the location of these wells sometimes
using force.
Simpson Desert
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Flora and Fauna:
Water-holding frog
Wedge-tailed eagle
Kestrel
Crested pigeon
Zebra finch
Galah
Corellas
Perentie
Spinifex
Poached-egg daisies
Grevilleas
Acacias
Sampire
Kati Thanda – Lake Eyre
Australia’s largest salt lake.
Periodically fills with water, which then
evaporates to leave a salty crust.
The extent of the water in the lake depends
on the monsoon in the tributary areas.
As the lake fills, 1000’s of birds migrate to
feed on insects and the small fish that
multiply in the lake. Some birds usually only
seen in seaside locations include: pelicans,
gulls and terns.
Dalhousie Springs
These hot, mineral springs rise from the Great
Artesian Basin. They are an oasis in the desert and
support unique species of fish that have evolved
there in complete isolation.
Simpson Desert
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Economic activity
Tourism
Temps often exceed 50 degrees C.
SA National Park Authorities close the area in these conditions.
Passes are required to enter the Simpson Desert Conservation Park
or Simpson Desert Regional Reserve.
Pets are banned as feral animals are 1 of the greatest threats to the
desert’s ecosystems.
Mining
A gas pipeline runs across the Simpson Desert, but there is no large
scale mining.
Livestock grazing
Cattle grazing occurs on the edges of this desert region.
Gibson Desert
Traditional Owners: Pintupi people
Location: central WA
.
• Sand dunes, gibber plains and small salt lakes.
• 1876, Earnest Giles first E to cross. He named
it after 1 of his team who died on the journey.
• Despite extreme dryness, underground water
is in the Officer Basin and Canning Basin.
Gibson Desert
Traditional Owners: Pintupi people.
Location: central WA
• Largest communities are at Kanpa, Patjarr, Kaltukatjara,
Kintore and Tjirrkarli.
• Warburton at the southern edge has its own airstrip.
• Pintupi people have a town centre at Patjarr, run by the
Ngaanyatjarra Council.
• They were moved out in the 1960’s, when the Au
government used the area for weapons testing.
• After the Pintupi people were removed their desert
homelands were declared a Nature Reserve, which
prohibited them from returning and living there. The
Pintupi have returned despite this prohibition.
Gibson Desert
• Lake Gruszka near Warburton is a surprisingly large
lake in the Gibson Desert. Surrounded by vegetation it
attracts ducks and other aquatic birds.
• Endangered Flora:
• Mulgara (related to the Tasmania Devil but only 20cm
long).
• Marsupial mole
• Ghost bat
• Black-footed rock wallaby
• Greater bilby
Gibson Desert
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Economic Activities
Mining
Reserves of copper, gold and diamonds.
Livestock Grazing
No suitable water sources = no cattle.
Feral camels have increased in numbers in recent years and
are a threat to the ecosystems.
• They graze on desert vegetation contributing to erosion as
the plants they eat die and no longer anchor the soil in
place.
• Sandalwood
• The Ngaanyatjarra Council is considering the possibility of
making economic use of the sandalwood trees in the area.
Little Sandy Desert
Traditional Owners: Mandilara people.
Location: centre of WA in the East Pilbara region. Part of the Rudall River
National Park
Sand dunes and low rocky hills.
Rudall River, or Karlamilyi, flows through the desert with
wetlands along the course, and drains into Lake Dora (which
becomes a salt lake when it dries up).
Thr rocky hills have some permanent water sources, and there
are man made holes created for the Canning Stock Route.
Town of Jigalong, with a population of about 400 mainly
Aboriginal people is on the edge.
Parnngurr and Punmu are 2 of the Aboriginal communities.
Caves and rock walls in the hills of this desert are rich in and
famed for their rock art.
Little Sandy Desert
• Flora and Fauna:
• Great variety of lizards, rocky hills perfect
habitat.
• Camels are responsible for damaging many
water sources.
• Recent studeis show an increase in feral cats
and a decrease in bilbies and mulgara.
Little Sandy Desert
• Economic Activities
• Tourism
• No facilities for tourists. Harsh and dangerous place for newcomers.
Water is hard to find but there are sudden, dangerous floods.
• Mining
• Mineral exploration is an important economic activity close to the
Little Sandy Desert. Including: copper and gold mining and uranium
exploration.
• Building of access roads effect the desert ecosystems but it also
brings employment and contribute to the Au economy.
• Mining workforce general fly in and out and do not reside
permanently in the desert.
• Livestock grazing
• Grazed in very small portion of the east of the LSD, as no suitable
water sources available for large scale grazing. Lack of grazing
means introduced weeds are not an environmental problem.
Strzelecki Desert
Traditional Owners: people.
Location: parts of SA, Queensland and NSW
• Sand dunes and salt lakes.
• Charles Sturt named it after the Polish
explorer, Paul Strzelecki. The Strzelecki Creek,
Cooper Creek and the Diamantina River all run
through the Strzelecki Desert.
• Rivers are often dry but may fill suddenly after
rain.
• The Strzelecki Regional Reserve protects part
of it.
Strzelecki Desert
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Flora and Fauna:
Dusky hopping mouse
Brolga
Mulgara
Dunnart
Sandy inland mouse
Long-haired rat
River red gum
Strzelecki Desert
• Economic activity
• Tourism
• Tourists visit to enjoy 4-wheel driving camping trips and a desert
experience.
• The Birdsville Track passes through the Strzelecki Desert.
• Mining
• The Strzelecki Track is used for mining access. The Moonba oil and gas
processing plant and the associated mining operations are important for
industrial developments in the Strzelecki Desert. Moonba uses bore water
and has its own airstrip.
• Livestock grazing
• Extensive livestock grazing in the Strzelecki Desert. An increase in the
number of goats grazing is contributing to damage of the desert
vegetation since goats can get into areas that are inaccessible for larger
grazing animals.
Sturt Stony Desert
Traditional Owners: Dieri, Yandruwantha, Yawarawarrka and Ngamini people.
Location: northeast of SA and in neighbouring parts of Queensland and NSW
• Gibber desert, meaning covered in stones.
• Stones are glazed with a natural colouring of iron oxide,
giving them a purple-reddish colour.
• The Aboriginal peoples used the hard stones to make tools
and weapons.
• Numerous massacres by white settlers of the original
owners occurred. In the 1880s the Warrhampa massacre
occurred at the Goyder Lagoon executed by cattle owners
against the Aboriginals.
• Charles Sturt and his team took their horses into the SSD
and the stones damaged the horses hooves and legs.
• A number of creeks drain into the SSD but they are mostly
dry except after rain.
Sturt Stony Desert
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Flora and Fauna:
Kowari
Saltbush
Grevillea
Sturt Stony Desert
• Economic Activity
• Tourism
• Diamantina Road and the Birdsville Track cross the SSD
and provide tourists with access to remote areas.
• Mining
• Gas and oil fields on the edge of the SSD.
• Livestock grazing
• Some parts are grazed, cattle use the underground
bore water. Despite the apparent lack feed, the SSD
manages to support a few cattle stations, as well as
kangaroos and smaller animals.
Tirari Desert
Traditional Owners: Dieri people (Numbering about 1,000 in the mid 1800s.
The Dieri Native Title Claim extends along the eastern edge of the Kati Thanda
–Lake Eyre).
Location: SA
• Sand dunes and salt lakes.
• Cooper Creek crosses the Tirari Desert but its bed is often
dry, except after rain.
• Part of the Tirari Desert is in the Kati Thanda –Lake Eyre
National Park.
• First European was Peter Warburton in 1866.
• Dieri language was studied and recorded in detail by
German Lutheran Missionaries who worked in the area in
1869. They ran a school for Aboriginal children where the
Dieri language was spoken and written. The remains of the
Killalpaninna mission are a SA Heritage Site.
Tirari Desert
• Flora and Fauna:
• Fossil remains of ancient types of ring-tailed possums
suggest the area was once much wetter with forest
tree species.
• Low wattle bushes
• Saltbush
• Grasses.
• After rains small shrubs and flowering plants bloom in
abundance.
• River red gum and Coolabah trees grow around
permanet water holes and springs.
Tirari Desert
• Economic Activities
• Tourism
• Tirari Desert is only visited by a small number of
tourists.
• No facilities for camping and visitors need to be
very experienced in survival in remote, arid areas
– Bear Grylls style!
• Livestock grazing
• Large cattle stations using underground water
sources.
Pedirka Desert
Traditional Owners: people.
Location: SA. Closest sizeable town is Oodnadatta and the northern border is
the Hamilton Creek.
• Stony or gibber desert (like GD and SSD) but
much smaller.
• Also low, red sand dunes.
Pedirka Desert
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Flora and Fauna:
Mostly Mulga scrub
Grasses
Saltbushes
Near the Hamilton River, River Red gums and
Coolabah trees.
• Short lived flower bloom after rains (as with
all Au deserts).
Pedirka Desert
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Economic activity
Mining
Petroleum, natural gas and coal exploration have occurred, but the lack of bore
water over the central part of the Pedirka Desert has limited economic
possibilities.
Rumbulara Ochre Mine operated during the 2nd WW, producing camouflage
pigments. IT has its own railway siding. No local water so it had to be brought in by
train and then truck. It employed 10 Aboriginal miners.
Mine was and is used by Aboriginal people for generations before Europeans
started mining.
Livestock grazing
Large part used for cattle grazing. Groundwater for cattle is accessed along the
western part.
Railway
During building of The Ghan Railway, there was a small side track called Pedirka,
used to load building materials and supplies.
Semi arid deserts
Desertification
Drought in Kenya means there is little water left for herds to drink and
many have died as a result. Maasi shepherds like this one now have to
drive their herds up to 45km to get water.
CAUSES OF CHANGE –
at least 5 3 of your study
specific details needed not just general statements
• Look at both human use of hot deserts and
natural change in your chosen case study. In class
I will have a visual that you can use to help you.
• The main natural cause of change is climate
change. In 9 of the 12 deserts studied by UNEP,
temperatures were rising faster than the global
average. You need to focus on the impact of
climate change in your chosen case study.
EXTENT OF CHANGE
WHY SHOULD WE CARE?
• All desert areas globally are being impacted. Some may
have more positive impacts than negative but in an
environment that is already difficult to live in plants
and animals that are highly adapted to this
environment and may be resilient are becoming
vulnerable as their micro habitats are changing.
•
• WHY SHOULD WE CARE?
• Using the 4 S’s or my use of terms such as Utility Value,
Intrinsic Value etc outline why your particular case
study should be looked after.
The Desert: Journey through the
Sahara lays bare effects of climate
change
• In our new special series, The Desert, CCTV
takes an epic journey through the Sahara to
explore how climate change is affecting the
world's largest hot desert, and the people
who inhabit it. Our journey begins in
Mauritania, near the Zarga Mountains, where
we meet the nomads of the Sahara.
MANAGEMENT
• * Looking at your specific case study explain a
range of management options being used.
These tend to focus on water conservation,
reducing soil erosion and limiting the spread
of desertification.
• * Evaluate the effectiveness of these.
https://www.britannica.com/science/c
old-desert
Management of Au deserts and
deserts in general
• Examples and statistics
• Need at least 2 of your own with detail
specific numbers/stats examples.
Evaluate the effectiveness of
management techniques
• Definition of evaluate:
• At least 1 in excellent detail
http://www.australiangeographic.com.au/topics/scienceenvironment/2016/04/australias-10-deserts
• http://www.ucmp.berkeley.edu/glossary/gloss
5/biome/deserts.html
• https://www.awa.asn.au/documents/Geograp
hy1_Comparing_Australia_and_Arab_Water.p
df
12% of the World’s biodiversity
hotspots are found in desert biomes.
• Causes of change can be classified as human
induced or natural.
Extent of change
• All desert areas globally are impacted. Plants
and animals are impacted as habitat is lost.
Life is already coping at the extremes –
resilient but often they live in micro-habitats
so are extremely vulnerable.
Why Care?
• Desert flora and fauna have utility value.
• Genes of flora and fauna could help develop
new crops and livestock that can cope with a
warming world.
• Could lose ancient cultures and landscapes
• Namibia – diet plant - california
Management
• Tends to focus on
• Planting trees – green belts – China
• Water conservation – more effective irrigation
systems.
• We will find examples from:
• Thar
Mojave
• Sahel
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