Extreme Environments

Question 1

What is a desert?

What is a dryland?

Answer 1

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.

Question 2

Why is most of Australia desert?

Answer 2

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Question 3

In what three ways have plants adapted to arid climates?

Answer 3

1) Succulence
2) Drought tolerance
3) Drought avoidance

Question 4

What are the adaptations of succulent plants? (4)

Answer 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.

Question 5

What is drought tolerance? (plants) (2)

Answer 5

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.

Question 6

What is drought avoidance? (2)

Answer 6

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.

Question 7

What is the Bilby and how is it adapted to survive in Australia’s outback. (3)

Answer 7

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.

Question 8

What is the Perentine and how is it adapeted to survive in Australia’s outback? (3)

Answer 8

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.

Question 9

How is the Red Kangaroo adapted to survive in Australia’s outback? (6)

Answer 9

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.

Question 10

How are buildings adapted in semi-arid areas?

Answer 10

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.

Question 11

How is clothing adapted in semi-arid areas? (3)

Answer 11

1) Loose-fitting clothes
2) Often white to reflect sunlight
3) Heads and faces often covered as protection from the sun, wind and sand.

Question 12

How is transport adapted in semi-arid areas? (2)

Answer 12

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.

Question 13

How is energy use adapted in semi-arid areas? (3)

Answer 13

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.

Question 14

What are the aboriginal beliefs and lifestyle? (4)

What is the main threat to their culture?

Answer 14

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.

Question 15

What are the main components of the aboriginal diet? (4)

Answer 15

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.

Question 16

Give three. facts about the aboriginal population.

Answer 16

1) Has 2/3 life expectancy of white Australians
2) Has Australia’s worst drug and alcohol abuse; homelessness is also problems.
3) Traditional lifestyle disappearing.

Question 17

Give four benefits and four problems of tourism in Uluru.

Answer 17

Benefits:
1) The Uluru Aboriginal culture centre educates people about aboriginal culture.
2) Guides are led by aboriginal people, the aim is to educate and entertain.
3) Income from admission fees goes towards the Anangu community.
4) Over 30 aboriginal people work in the park and the parks management is dominated by aboriginal owners.
Problems:
1) Culture can be exploited, paintings are produced to suit visitors tastes rather than preserve culture.
2) People climb the rock even though it is against Anangu spiritual beliefs. and they don’t learn about aboriginal culture when they visit.
3) Aborigines are exploited through a disney-like attraction.
4) Cultural dilution of Aboriginal beliefs, and introduction of western language and beliefs which has lead to drug and alcohol abuse among Aborigines.

Question 18

Give 4 main impacts of climate change in the Australian Outback.

Answer 18

1) Temperatures in the outback may be between 1.4-5.8ºC higher by 2100.
2) Rainfall will decrease in Southern Australia so the area of the desert will move south, desertification.
3) Increased drought due to increase in evaporation in the north and east.
4) Bushfire weather will continue across south-eastern, central and north-eastern Australia.

Question 19

What is desertification?

Answer 19

Desertification is when wind erodes away the top layer of soil that contains the nutrients which plants need to grow, it results in the area becoming desert and plants not being able to grow.

Question 20

In what three ways can human action lead to desertification?

Answer 20

1) Overpopulation - an increase in population leads to more intensive farming to get more food from the land, eventually the soil becomes infertile and is eroded by wind turning the area into desert.
2) Overgrazing - Cattle are farmed on less and less land, they overgraze remaining grasslands which leads to desertification.
3) Deforestation - trees are cut down due to increased demand for firewood, the soil becomes exposed to wind and is more easily eroded leading to desertification.

Question 21

In what two ways can a change in rainfall pattern caused by climate change lead to desertification?

Answer 21

1) If the rains don’t arrive, the grasslands die, this leaves the soil exposed which can then be easily eroded by wind.
2) When the rains do arrive the exposed soil is easily washed away by the heavy rain.

Question 22

What is bunding, which charity has helped to fun the project in the Sahel and what impact (3) has bunding had?

Answer 22

Bunding involves putting lines of stones across a slope to stop rain water running away and also to stop the wind from eroding topsoil. It is cheap and easy to use.
Oxfam
1) It has improved soil quality and slowed down the loss of water.
2) It allows water time to infiltrate into the top soil.
3) Which means farming has improved and food production has increased.