1. The Desert Ecosystem
A dry hot area is called a desert. An area that
borders a desert is called a desert scrub.
Deserts range from dry to dry to hot to cold and
they receive very little precipitation. There are
different plants and animals that are found at
different deserts all around the world. During the
day deserts are hot but temperatures fall to
40-50 degrees or more during the night. This is
due to the lack of evaporation in the atmosphere
and heat escapes easily at night. During the day
evaporation is blocked by sunlight. Deserts are
30 degrees north and south from the equator.
Characteristics of a hot and dry desert:
Atmosphere contains very little humidity
therefore rays of the sun are not really blocked.
The Sahara desert
Mean temperatures: 20 to 25 degrees.
• It is the world largest
Evaporation is greater than rain fall (rain often
hot desert
evaporates even before it reaches the ground).
• Temperature: range
from over 130 degree to
below freezing
• Foxes, Dama
Gazelles and Saharan
Horned vipers are just
some of the animals that
Small desert animals, such
as the kangaroo rat, live in small holes
Soil in the desert is under ground during the day and come out
mainly made up of sand Annual average rainfall is about 250mm. This only when it’s dusk or night time; when it is
and bits of rock. It has shows in 5% of Earth’s surface has this amount of cooler. Being small makes it easier for them
almost no organic content rainfall. In winter, the wind is very strong and harshly to lose heat from their bodies. Small desert
and not many plants can snowy days continue. In summer time average mammals have special adaptations to their
survive in this soil. It tends temperature is 41-43℃. Often there is no rainfall for kidneys so that they excrete urine that
to become alkaline near years, but having sudden flooding for few days. contains very little water. Other mammals
water sources and most have light coloured coats which reflect more
plants cannot survive in Influence of climate is different by different animals, light. Not only do pale colours ensure that
these conditions, though but they all have structure of body for absorbing and the animal takes in less heat from the
some, like the date palm, conserving water easily. Plants are short and having environment, it also helps them blend in the
can. As a result, the desert thorn, small leaves, gray to light green colour and desert surroundings. Reptiles have a natural
is not a very vegetated deep roots. Having smallest mass as possible, adaptation, they have thick skin that
closing air hole for daytime and having special minimizes water loss. Some lizards may
vessels for keeping water. have longer legs, so they absorb less surface
heat while running. Plants have deep or wide
For animals, they drink water if possible, but they eat root system to collect as much water as
possible. Also they need to make sure they