Mojave Desert

• Where is the Mojave desert?

  Southeast and central California, parts of Nevada, Utah and northwest Arizona
• What type of desert is it?

  - Rain shadow desert

  - Tehachapi, San Gabriel and San Bernardino Mountains

  - Death Valley 86 m below sea level

  - Altitude range 1500 to -86
• Temperature


  - Summer often 49°C

  - Winter often below freezing point

  - large Diurnal range
• Climate


  - Hot

  - 330 to 50 mm annual rainfall (arid)

  - high pressure atmosphere
• Death Valley


  - 86m below sea level

  - hottest area of North America

  - June August regularly reach 50°C

  - National Park
• National Parks


  - Death Valley

  - Joshua Tree National Park

  - Mojave National Preserve
• Why does it have a higher density of vegetation that other deserts?

  water table is high throughout the area
• What type of plants

  halophytic and xerophytic plants
• How many plant species?

  1750 - 2000
• Adaptations of plants


  - Thick waxy skins (reduce water loss)

  - Store water inside them

  - Small leaves/ spikes which reduce transpiration

  - long tap roots to get to water sources

  - roots spread horizontal/ shallow to catch rainwater/ dew

  - low density (spaced out) so have enough water + nutrients (less competition)

  - Many small to reduce surface area for water loss

  - dormant seeds (periods of drought grow when rain)

  - Thorns (stop animals eating them)

  - ephemeral (short life span for species)

  - halophytic (cope with high salinity content)
• Plants


  - barrel cactus (succulent- thickened to reduce water loss)

  - creosote bush (ephemeral - short life span)

  - Joshua tree (halophytic - high salinity adaptations)
• Soil


  - poor and coarse in texture

  - lowest level of organic productivity of any soil or ecosystem in the world

  - very thin because chemical weathering cannot happen without water

  - low density of vegetation

  - low organic matter so worse soil

  - water easily sinks and when resurfaces has high salinity from bedrock

  - concentrations of minerals in water create high alkaline soil