deserts - thar

Question 1

challenges (soil)

Answer 1

sandy
not very fertile - little organic matter
drain quickly so little surface water
evaporation draws salts to the surface, leaving white powder on the ground

Question 2

challenges (landscape)

Answer 2

mainly sandy hills with sand dunes and clumps of thorn forest vegetation - mixture of small trees, shrubs and grasses

Question 3

challenges (rainfall)

Answer 3

between 100 and 240mm per year
summer temperatures in July can reach 53 degrees C

Question 4

opportunities (tourism)

Answer 4

10000s people visit each year
safaris on camels in Jaisalmer
annual desert festival each winter
local people provide food and accommodation, act as guides, rear and look after camels

Question 5

opportunities (mineral extraction)

Answer 5

used all over india and exported all over the world
- gypsum (plaster, cement)
- feldspar (ceramics)
- phosphorite (fertiliser)
- kaolin (whitener in paper)

Question 6

opportunities (stone)

Answer 6

at Jaisalmer Sanu Limestone is the main source of India’s steel industry. quarried near Jodhpur - for construction industry

Question 7

opportunities (energy, coal)

Answer 7

Giral thermal energy plant
extensive lignite coal deposits in parts

Question 8

opportunities (energy, oil)

Answer 8

Barmer field oilfield - makes large contribution to state revenues

Question 9

opportunities (energy, wind)

Answer 9

Jaisalmer wind park - constructed in 2001, India’s largest wind farm

Question 10

opportunities (energy, solar)

Answer 10

ideal conditions
- Bhadla solar park - spreads across 40km, generates enough energy to meet Rajasthan’s needs

Question 11

opportunities (farming)

Answer 11

most involved in subsistence farming
commercial has grown because of irrigation, Indira Gandhi in 1985
wheat and cotton thrive

Question 12

challenges (extreme temp)

Answer 12

health challenges for people working outside, can’t work outside for too long so not efficient
low rainfall + high evaporation rates - water shortages, essential for farming mining and tourism
dehydration of animals and plants - decrease biodiversity and farming

Question 13

challenges (water)

Answer 13

population grown, industry developed - demand increased
low rainfall, high temp strong winds - high evaporation rates

Question 14

Indira Gandhi Canal

Answer 14

650km long
supplies Jaisalmer and Jodhpur - 3500km^2
constructed in 1958
fresh water source for drinking and farming

Question 15

challenges (inaccessibility)

Answer 15

limited road networks
tarmac melts
sand blown onto roads
many places only accessible by camel

Question 16

climate

Answer 16

lack of rain - less than 250mm of rainfall per year, dryness and aridity, high pressure, very high daytime temperatures, lack of cloud - temperature plummets to below freezing in night during winter

Question 17

where are hot deserts found

Answer 17

dry continental interiors (away from coast) approx. 30 N and 30 S

Question 18

plants and animals

Answer 18

find ways of surviving the hostile conditions, plants tend to have small leaves or spines to limit water loss and have long roots to reach underground sources

Question 19

interdependance

Answer 19

very fragile environment, high levels of interdependence
plants and animals adapt to store water, lose heat and seek shelter, sand perfect for burrowing
plant seeds remain dormant for long periods until rainstorms arrive

Question 20

hot desert animals adaptations

Answer 20

many animals are nocturnal and live in burrows in the day, large eyes help them hunt for food at night, snakes have water proof skin and produce small amounts of urine
camels - long eyelashes, broad flat hooves, thick wooly fur, tough mouth, fat stored in hump

Question 21

threats to biodiversity (climate change)

Answer 21

changing patterns of rainfall, increased frequency and intensity of droughts threated ecological balance

Question 22

threats to biodiversity (wildfires)

Answer 22

may become more common, replacing slow growing shrubs with faster growing grasses, altering the ecosystem

Question 23

threats to biodiversity (overgrazing, overcultivation)

Answer 23

excessive gathering of fire wood in desert margins can destroy vegetation, exposing soil to erosion by wind and rain, leading to desertification

Question 24

threats to biodiversity (desert tourism)

Answer 24

off-road vehicles can damage vegetation and disturb wildlife

Question 25

what is desertification

Answer 25

when land gradually turns into desert, usually on fragile margins of existing deserts, mainly due to humans, land stripped of vegetation, exposed to water and wind erosion, top soil eroded away

Question 26

where is desertification a problem

Answer 26

mostly on boarders of existing deserts
an estimated one billion people live in the areas at risk
not just in poorer countries e.g. US

Question 27

what causes desertification (climate change)

Answer 27

results in drier conditions (more droughts) and unreliable rainfall. climate very fragile - slight changes to temperature and rainfall can have serious impacts. on average it now rains less than it did 50 years ago

Question 28

what causes desertification (soil erosion)

Answer 28

when vegetation is destroyed, it’s exposed to the wind and rain, making it vulnerable to erosion
deforestation, mining, urban developments

Question 29

what causes desertification (population growth, overgrazing)

Answer 29

results in land close to deserts being overgrazed - too many animals to be supported by the limited vegetation. when vegetation has been destroyed, land will turn to desert.

Question 30

what causes desertification (overcultivation)

Answer 30

resulting from the need to produce more food, can lead to the soil becoming exhausted - will turn to dust and become infertile.

Question 31

what causes desertification (fuelwood)

Answer 31

population growth leads to the removal of fuelwood, removing too many tree branches can lead to them dying

Question 32

water and soil management in desert

Answer 32

irrigation - water from underground sources or from rivers and canals can be sprayed into crops or used to flood fields. too much can lead to salinisation - high rate of evap, build up of salts on surface, soil fertility reduced, plants die
ponding banks - areas of land enclosed by low walls to store water
contour traps - embankments built along contours to prevent soil from being washed down

Question 33

where is the thar desert?

Answer 33

major hot desert, stretches across north-west india and into pakistan, covers an area of 200000km^2
most densely populated desert in the world

Question 34

tree planting in desert

Answer 34

tree roots bind soil together and leaves and branches act like an umbrella, protecting soil from rain
in thar desert, community led project has planted one million trees to form a ‘green wall’ at Bikaner in Western Rajasthan to reduce soil erosion by wind and reduce destertification

Question 35

appropriate technology in desert

Answer 35

in burkina faso lines of stones have been used to reduce soil erosion, uses basic tools and trucks to transport stones, low stone walls between 0.5 and 1.5 m along contours, walls trap water and soil from rain, increases crops by up to 50%, reduces desertification.