Extreme Environments Flashcards
What is a desert?
What is a dryland?
A desert is an area that receives less than 250mm of rainfall each year.
It is a semi-arid environment with an annual rainfall of around 250mm-500mm.
Why is most of Australia desert?
a
In what three ways have plants adapted to arid climates?
1) Succulence
2) Drought tolerance
3) Drought avoidance
What are the adaptations of succulent plants? (4)
1) They can absorb large amounts of water very quickly through extensive, shallow root systems and they can store this water for long periods of time.
2) Their stems and leaves have waxy cuticles which makers them almost waterproof when their stomata are closed.
3) Their metabolism slows down during drought and their stomata close permanently, so their is almost no water loss, so there is almost no growth during drought.
4) They are attractive to animals because they contain lots of water so many of them have toxic spines to ward off animals or are camouflaged.
What is drought tolerance? (plants) (2)
1) During drought some plants have adapted so that their leaves fall off to stop water being lost from the plant through the stomata in the leaves.
2) Some plants have developed really deep roots, so they are able to reach water deep underground.
What is drought avoidance? (2)
1) These are annual plants that only flower once.
2) After flowering they die, but leave behind their seeds, that can survive for years before growing into plants when it rains again.
What is the Bilby and how is it adapted to survive in Australia’s outback. (3)
The Bilby is a small marsupial.
1) It is nocturnal to avoid dehydration in the daytime heat.
2) It burrows for moister, cooler conditions.
3) It has low moisture needs, obtaining enough from its food such as bulbs, fungi and insects.
What is the Perentine and how is it adapeted to survive in Australia’s outback? (3)
The Perentine is a lizard which can grow up to 2.5 metres long.
1) It digs, burrows and deep rock crevices.
2) It hibernates from May to October to avoid the cold.
3) It has low moisture needs.
How is the Red Kangaroo adapted to survive in Australia’s outback? (6)
1) Hopping is a fast and energy efficient form of travel and enables it to find food in the sparsely populated desert.
2) It feeds at dawn and dusk when it is cooler.
3) Sleeps throughout most of the day.
4) Dew is an important part of its water intake.
5) Rain triggers a hormonal response in the females so breeding only happens in the rains.
6) Licks its forearms to cool off.
How are buildings adapted in semi-arid areas?
1) Flat roofs collect rain water.
2) Walls are painted white to reflect sunlight and keep buildings cool.
3) Walls are often thick to help maintain the cool temperature inside.
4) Windows are small to keep temperatures and sunlight low.
How is clothing adapted in semi-arid areas? (3)
1) Loose-fitting clothes
2) Often white to reflect sunlight
3) Heads and faces often covered as protection from the sun, wind and sand.
How is transport adapted in semi-arid areas? (2)
1) Camels are used in some areas as they can travel so far without needing water.
2) Nowadays 4x4 cars are the preferred mode of transport.
How is energy use adapted in semi-arid areas? (3)
1) Many buildings are fitted with solar panels.
2) There are strong winds so wind turbines often work very well.
3) Modern building have air conditioning.
What are the aboriginal beliefs and lifestyle? (4)
What is the main threat to their culture?
1) Their beliefs focus on the land, they see themselves as caretakers of the land.
2) Their crafts are based on hunting, music and tribal celebrations.
3) They built dams across rivers to catch fish and made pools where birds would gather.
4) They traditionally survived as hunters and gatherers.
As generations split and younger people move to the cities, stories about care of the land are being lost.
What are the main components of the aboriginal diet? (4)
1) Fruits - tomatoes, limes and bannans
2) Seeds - Wattle seeds used in biscuits, drinks and dressings.
3) Grubs - witchetty grubs are the larvae of moths and beetles, which are eaten raw or cooked.
4) Meat - kangaroo, crocodile or emu.