Deserts come in all shapes and forms.Technically,a deserts is defined as a very dry piece of land.Deserts receive less than 250 mm of rainfall each year.most people imagine deserts as full of sand,but in fact,many deserts are not full of massive sand dunes.Mountain ranges,gravel plains,salt flats,and rock beds characterize most deserts.Many desert are formed because tall mountains block precipitation.
There are four major types of deserts:hot and dry,semiarid,coastal and cold.The Sahara Deserts ,the Gobi Desert in China,and the Mojave Desert in Carifornia are examples of hot and dry desert.The soil is very rouge with shallow or rocky sections.In these deserts,temperatures can reach 49 degrees Celsius,which is very hot.It these deserts to drop to minus 18 degrees Celsius at night.
Other deserts are called semiarid deserts.These are deserts with temperatures that are not as hot.They have more moderate temperatures.Some semiarid deserts can be found in Greenland and Utah.They usually have a greater variety of ground-hugging bushes or shrubs than deserts like the Sahara.Their highest temperatures rarely goes above 38 degrees Celsius .The soil is sandy with small rock scattered about the ground.Many plants is semiarid deserts have shiny leaves.Shiny leaves allow a plant to save energy during the cool evenings.This is called conserving heat.These plants also provide a good place for insects to seek shelter.