Hot Deserts - P1 SEC B

Question 1

characteristics of hot deserts?

Answer 1

• 30N/S equator
• less than 250mm rain/yr

Question 2

climate of hot deserts?

Answer 2

• at these latitudes , air that has risen at Equator descends forming perisistent belt of high pressure
• causing lack of cloud, high temp in day, low temp at night

Question 3

plant adaptations ?

Answer 3

• horizontal root system
• store water in roots,stems,leaves or fruits
• small leaves,spines,waxy coating reduce water loss
  (cacti have spines - reduce SA for water loss)
• long traproots (7-10m deep to reach groundwater)
• many plants are slow growing - requires less energy, so less food needed, less water loss

Question 4

animal adaptations?

Answer 4

• live in areas of good water supply/biodiveristy
• kangaroo rats dont need to drink water (get water from food)
• desert fox have thick fur on feet protecting from hot ground
• large SA maximises heat loss
• fatty hump that provides energy in times of food shortage

Question 5

how is vegetation effected by environment in desert?

Answer 5

Sparse/low growing as it is effected by lack of rain /infertile soils

Question 6

how is soil impacted by desert’s environment?

Answer 6

Dry,thin due to HIGH TEMPS /STRONG WINDS blow away layers of topsoil

Question 7

Interdependence of climate ?

Answer 7

Dry/ dries out soil
- determines type of plant and animal that can survive extreme heat

Question 8

Interdependence of animals?

Answer 8

Adapted to harsh climate /effected by vegetation as they have to roam large areas to eat

Question 9

Environmental challenges to biodiversity?

Answer 9

• dry conditions
• high temps
• rainfall

Question 10

Location of hot desert case study?

Answer 10

NW india into Pakistan
- covers area of 200,000km2 mostly in Rajastan

Question 11

Opportunités for development in Thar desert ?

Answer 11

MINERAL EXTRACTION: - valuable reserves of minerals ( Gypsum, Feldspar , Phospherite , Kaolin)
ENERGY
FARMING : subsistence farming - grazing animals on grassy areas/cultivating veg /fruits trees
- commercial farming by IRRIGATION (INDRA GHANDI CANAL) –> creates jobs/increase economy

TOURISM : tens of thousand visit per yr
- desert safaris are popular /annual Desert Festival attracts tourists

Question 12

How is Thar Desert a good energy source ?

Answer 12

COAL: extensive lignite coal deposits in parts of desert
OIL: oilfield in Barmer District which could help economy
WIND : developing wind power (Jaisalmer Wind Park in 2001)
SOLAR : Bhaleri solar power used in water treatment

Question 13

Challenges of hot deserts ?

Answer 13

EXTREME TEMPS : exceeds 50C in summer
- hard to work outside / evaporation lead to water SHORTAGE

WATER SUPPLY : as farming develops /population grows DEMAND for water Increases
- low annual rainfall /high temps cause scarce water supply

ACCESSIBILITY: extreme weather /vast barren areas , there is limited road network

Question 14

What is the Indra GHANDI Canal ? And the importance ?

Answer 14

Main form of irrigation
- transformed extensive area of desert /revolutionised farming
- provides drinking water

Question 15

What is desertification ?

Answer 15

When land gradually becomes desert due to over grazing

Question 16

Causes of desertification?

Answer 16

CLIMATE CHANGE : drier/unreliable rain
POPULATION PRESSURE: - lead to land near deserts to be overgrazed , as too many animals supported by limited vegetation
- vegetation is destroyed —> desertification

SOIL EROSION : - vegetation destroyed leaving soil exposed to wind/rain, eroding soil
OVERCULTIVATION : need to produce more food can lead to soil becoming exhausted
POPULATION GROWTH : increase demand of fuel wood (trees stripped of branches)/ more demand for food/water -> MINES/ INDUSTRY

Question 17

how to reduce desertification?

WANT

Answer 17

WATER/SOIL MANAGMENT: too much irrigation in commercial farming leads to SALINATION (build up of salts due to high rate of evaportation–> reduce soil fertility/kills plants)
e.g ponding banks/contour traps

NATIONAL PARKS
TREE PLANTING : - tree roots bind soil tgt / branches provide shade/grazing for animals
APPROPRIATE TECH : using methods/materials that are appropriate to level of development
e.g stone lines

Question 18

how to reduce soil erosion as part of soil managment?

Answer 18

PONDING BANKS : area of land enclosed by low walls to store water
CONTOUR TRAPS: embankments built along contours of slopes to prevent washing away of soil during rainfall

Question 19

e.g of water/soil managment?

Answer 19

Badia, jordan
part of Tai Rimah Rangland Rehabilitation Project to reverse desertfication caused by overgrazing they built:
- low stone walls to stop water running down slopes
- this water is used to irrigate newly planted ATRIPLEX shrubs that are well adapted (atriplex holds soil tgt/provide grazing)
- as soil conditions improve, plants start to grow

Question 20

what can the prospis cinaria tree be used for?

Answer 20

• good quality firewood
• strong wood
• shaded/moist growing conditions
• roots stabalise sand dunes