Hot deserts Flashcards
hot deserts location
- between 20-30 degrees north and south of the equator
- they are in a large band between the tropics
- they are inhabited in every continent except Europe
hot deserts climate
- arid and dry
- receives 250mm of rainfall or less
- temperature can range from 50 degrees in the day to 0 degrees at night
hot desert soil
- salty soils due to salinisation
- sandy and rocky
- rapid evaporation (crystallisation of salt)
interdependance
The biotic and abiotic components of an ecosystem rely on each other, e.g vegetation ➙ animals eat them
light ➙ plants photosynthesise
animal adaptations
fennec fox: -sandy coloured skin to camouflage -large 6mm ears to keep them cool -sweep (tail) to change direction from predators camel: -hump to store fat -hooves to give their feet a larger surface area -thick lips to eat prickly plants
plant adaptations
cacti:
-large, fleshy stems to store water
-small, waxy leaves to minimise transpiration losses
-spikes to discourage predators
flowering plants:
-brightly coloured petals to attract insects so they can pollinate
-they are epthermals - able to complete their life-cycle in less than 1 months
thar desert location
- Asia, on the border of India and Pakistan
- 27 degrees N
thar desert tourism
Jaislamer - sandstone fort, spiritual, merchants’ houses, camel safari
thar desert farming
- uses irrigation
- Indira Gandhi Canal (650km)
- cash crops - cotton and wheat
thar desert energy
- wind and solar
- long hours of sun for solar
- wind farms
thar desert mining
- mineral rich - gypsum, feldspar, kaolin
- limestone - largest supply in India used in steel industry
- marble - used in construction
challenges - tourism in the thar
- use up scarce resources (water)
- water pools within the fort which erodes the sandstone
- tourism paradox occurs
negative impacts - development opportunities in the thar
- mining is unsustainable
- commercial farming ➙ over grazing ➙ over cultivation ➙ soil erosion
- irrigation ➙ salinisation
- nomadic herders can’t herd camels
Desertification
when desert fringe areas become dry and degraded
causes of desertification
- population increase (demand more food)
- overgrazing and over cultivation
- deforest desert fringes
- climate change
desertification - climate change
- makes temperatures hotter
- means water evaporates rapidly
- causes dryer soils which crack ➙ less vegetation ➙ soil erosion
desertification - population factors
- overgrazing ➙ large number of animals ➙ eat more vegetation
- over cultivation ➙ fewer nutrients in soil ➙soil is more vulnerable to erosion
- deforestation ➙ less interception and washes top layer off the soil when rainfall comes
appropriate technology (apps)
-technology suitable for: affordability, people, place, sustainable -appropriate technology lasts into the future
preventing desertification- planting trees
- roots bind soil together - prevents it from being eroded
- intercepts rainfall - keeps soil fertile
- roots contain moisture - helps fill up wells
- provided shade for plants and people
preventing desertification - water and soil management
- stone lines - traps precipitation, encouraging infiltration, crops can be grown
- acacia trees
- crop rotation - land recovers before it is used again
sahel
desert fringe area located south of the sahara desert in africa
subsistence farming
only growing enough to support family and themselves
irrigation
supplying land with water through a network of canals
salinisation
the increase in salt levels of soil due to water evaporation leaving salts and chemicals behind
great green wall
Plan that calls for a wall of trees to divide the semi arid Sahel from the Sahara
