Hot deserts key terms Flashcards
Desert
An arid environment receiving low levels of precipitation
Aridity index
Ratio between the precipitation and the potential evapotranspiration
Arid
Less than 250mm annual precipitation
Semi-arid
250-500mm annual precipitation
Hyper-arid
An aridity index less than 0.05
Diurnal range
The difference between the daytime and nighttime temperatures
Insolation
The incoming solar radiation that reaches the earth’s surface
Aridisols
An order of soils including infertile alkaline & saline soils of desert areas characterised by accumulations of mineral salt at or near the surface
Sierozems
Darker soils with the presence of some organic material developing below ‘desert shrub’
Raw mineral soils
Course soils that are often rocky due to physical weathering, tending to be slightly alkaline and unproductive
Leaching
When there is little downward movement of minerals in the soil
Sand sea
Areas of deserts that are constantly mobile
Primary productivity
The rate at which energy is converted to organic substances by photosynthetic producers
Xerophytes
A plant that has adapted to survive with very little water
Phereophytes
A plant with a deep root system that draws its water supply from a nearby water table
