Paper 1: The Living World - Hot deserts and their fringes Flashcards
Causes for coastal deserts climate
-cold ocean current = precipitation over sea
-as it reaches the land = air is dry
-air warms up over land = evaporation
-no rain in desert
Causes for Hot and dry deserts
-at the equator = air carries lots of moisture = low pressure
-rains
-air spreads out north/south of equator
-dry air settles at 30 degrees = high pressure
-no water vapour = no rain
low pressure
-cold weather and rain
high pressure
-sun
-warmer weather
Causes for rain shadow deserts climate
-air passes over ocean + evaporates lots of water
-mountain forces water up = condenses to rain
-rainshadow region = air has passed over mountains
-no rain as water vapour is used up
Saguro cacti adaptations
-thick fleshy stem
-small spiny leaves
-thick waxy surface
-shallow/spread out roots
-deep roots
Saguro cacti adaptations - thick fleshy stem
-store large amounts of water after rainfall
-expands with water
Saguro cacti adaptations - small spiny leaves
- reduce water loss through transpiration
-deter predators
-protect itself from competitors
Saguro cacti adaptations - thick waxy surface
-reduces transpiration through stem
Saguro cacti adaptations - shallow/spread out roots
-maximise water absorption after rain
-before it evaporates on hot ground
Saguro cacti adaptations - deep roots
-access to deep water stores
-groundwater stores
Lichen
-don’t need soil to grow
-grow on rocky surfaces
-use organic acids to break down rock and use its nutrients
Desert poppies
-seeds germinate after heavy rain
-grow very quickly
-lie dormant for year
-bright flowers attract insects = cross pollination
Biodiversity low in Sahara
-no range of plants and animals
-harsh survival conditions
Diurnal temperatures
-drop in temp during the day to at night
Where is the Sahel region
fringe of the Sahara desert
Difference in climate of Sahara and Sahel
-sahel= tropical, semi-arid not sunny but windy
-sahara = seasonal hot temp (33degrees)
Differnce of plants in Sahara and Sahel
-Sahel - acacia and baobab trees
Acacia tree adaptations
-survive droughts
-deep roots = groundwater stores
-fire resistant
-sharp thorns = deter animals
Baobab trees
-produces leaves in wet - season
-small leaves = less water loss
Soil profile of Sahel
- top layer is fertile
-below layers are infertile
-bottom layers = nutrients released by weathered rock
Camel adaptations
-survive long time w/o drinking
-2 sets of eyelashes + slit-like nostrils protection from sand
-little sweat
-fat respire for water (humps of fat)
-thick layer for shade on top of body
-thin fur everywhere else = heat loss
Camel adaptations - large sa:v ratio
-keeps them cool
-more places for heat to escape from
Camel adaptations - flat feet
-prevent from sinking in sand
Camel adaptations - concentrated urine
-lose little water from urination
-kidneys concentrate it
Cheetah adaptation -
-pale yellow with brown markings
-pale fur
-hunts early morning
-survive with very little water
Cheetah adaptation - pale yellow fur w/ brown markings
-camouflage
-hide from prey