Booklet Two - Explanations And Definitions

Question 1

Characteristics of a hot dessert

Answer 1

Subtropics between 20-30 n and s from equator
Tropic of Cancer and Tropic of Capricorn
Arid - dry and hot
High pressure so clear skies
Heat
Low biodiversity

Question 2

Climate of hot desserts

Answer 2

Clear skies so hot in the day cold at night

Question 3

Water

Answer 3

In short supply for most of the year
When rainfall does occasionally happens it is torrential downpours and can lead to flash flooding
Rapid evaporation

Question 4

Soils

Answer 4

Typicall sandy stomy and dry contain little organic matter
Infertile
When it does flash flood plants rapidly grow
Rapid evaporation- salutation

Question 5

Plants and animals

Answer 5

Low biodiversity
Leaves are thick and waxy
Plants have developed ways of storing water in roots cacti or succulents
Extensive root networks 10m
Rapid life cycles
Nocternal
Live in burrows
Large ears
Games hump stores fat
Long interdtine

Question 6

People

Answer 6

Desert fringes are sparsely vegetated and used by people for farming

Question 7

Interdependence In desserts

Answer 7

Complex food webs
Adaptions of plants and animals to the climate
Coexistence of species
Damage of human behaviour

Question 8

Issues with biodiversity in hot desserts

Answer 8

Have low biodiversity as low rainfall and lack of available water
Where water is present however rich biodiversity
Hot desserts are very fragile and the slightest change can have disastrous consequences

Question 9

Case study example

Answer 9

The western dessert

Question 10

Development opportunities in the western dessert

Answer 10

Mineral extraction
Energy
Farming
Tourism

Question 11

Mineral extraction in the western desert

Answer 11

There are rich reserves of copper uranium and coal
Copper is mined in the Sonoran dessert near Arizona
Elsewhere developments have been limited due to environmental concerns

Question 12

Energy in the western desert

Answer 12

Solar energy eg Sonoran solar project for 100000 homes
Oil in Arizona operated by indigenous people
HEP from lake mead

Question 13

Farming in the western desert

Answer 13

Irrigation enables commercial farming
Eg coachella valley pepper grapes
Water extracted from aquifers
Irrigation canals used in large scal farming

Question 14

Tourism in the western dessert

Answer 14

National parks eg Grand Canyon
Lake mead and powell for water sports
Las Vegas - 37 million a year

Question 15

Challenges facing hot desserts

Answer 15

Water supply
Extreme temperatures
Inaccessibility

Question 16

The challenge of water supply in the western desert

Answer 16

Water transfer from river Colorado has supplied drinking water and irrigation since the hoover dam
Piped water now
Problem as demand increases and temps rise due to climate change

Question 17

The challenge of extreme temps

Answer 17

Average temp in 27
Can go above 50 in the summer
Working outside can be hard for farmers
And high temps lead to rapid evaporation and water shortages
Plants and animals have to adapt
Houses have think whitewashed walls

Question 18

The challenge on inaccessibility

Answer 18

Low density population so lack of surfaces roads
Route 66

Question 19

Causes of desertification

Answer 19

Climate change
Population growth
Removal of feul wood
Overgrazing
Over cultivation
Soil erosion

Question 20

Desertification due to climate change

Answer 20

Fringe areas are semi arid and rely on low rainfall
Since 1970 Sahel experiences significantly less rainfall
Causing more droughts

Question 21

Desertification due to population growth

Answer 21

Sahel increased by 30 million
Demand for food has increased putting enormous pressure on the land leading to vegetation destruction in order to plant crops soil erosion and poor management leading to desertification

Question 22

Removal of fuel wood

Answer 22

Millions of people who live in semi arid conditions rely on wood as their primary source of fuel
When land becomes stripped of its trees can lead to soil erosion

Question 23

Desertification via overgrazing

Answer 23

Strip the land of vegetation leave it bare and vulnerable to soil erosion
Can happen because land is reduced
Natural causes
Or government pressure

Question 24

Desertification via over cultivation

Answer 24

Overcultivated for growing crops exhausting the soil of its nutrients
Semi arid areas already contain less nutrients so will become dry and infertile

Question 25

Desertification via soil erosion

Answer 25

Soil is left bare
Baked by sun
Washes away top soil
Left behind infertile

Question 26

Strategies to reduce risk of desertification

Answer 26

Water and soil management
Tree planting
Use of appropriate technology

Question 27

Water and soil management

Answer 27

Dresses the problem of intense rainfall
Involves water storage and attempts to control surface flow of water
Bunds - low rock walls interrupting the downward flow of surface water so soul is deposited on the side and can be cultivated

Question 28

Tree planting

Answer 28

Trees act as umbrellas protecting the soil and their roots, bind the soil together, preventing it from being washed or blown away
Great green wall plant trees across the southern edge of the Sahara desert

Question 29

Use of appropriate technology

Answer 29

Bunds
Alternative cooking devices such as efficient, stoves that only bone small amounts of wood