LIFE IN THE DESERT

NAME – CHINMAY PUNDIR CLASS – VII –B ROLL NO. – 13SCHOOL NAME - KENDRIYA VIDYALAYA SECTOR 2 R.K PURAM NEW DELHI -22

MEANING OF DESERT

1. A desert is a barren area of land where little precipitation occurs and consequently living conditions are hostile for plant and animal life. 

2. The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation. About one third of the land surface of the world is arid or semi-arid. 

TYPES OF DESERT

1.Cold Desert

2.Hot Desert

COLD DESERT Cold deserts are found in the Antarctic, Greenland, Northern and Western China, Turkestan, Iran and the Near tic area. Many nomads have settled on farms in the Gobi Desert and it was crossed as early as the 13th century by Genghis Khan. Cold deserts can also be found in certain mountainous areas, such as the Great Basin area of western United States.

HOT DESERTThe hot deserts of the world are located between 15° and 30° north or south of the equator. This is a zone of subsiding or sinking air. Air that rises due to the intense heat at the equator divides to flow north and south. When it reaches 15° to 30° it begins to sink because it has lost so much of its heat. This sinking air creates a zone of high pressure. As the air is sinking, no clouds can form and a lack of clouds means these areas are very dry.

Climate of desert Desert climate also known as an arid climate, is a climate that does not meet the criteria to be classified as a polar climate, and in which precipitation is too low to sustain any vegetation at all, or at most a very scanty shrub.An area that features this climate usually experiences less than 250 mm (10 inches) per year of precipitation and in some years may experience no precipitation at all.

There are usually 2 or three variations of a desert climate: a hot desert climate a cold desert climate and, sometimes, a mild desert climate Furthermore, to delineate "hot desert climates" from "cold desert climates", there are three widely used isotherms: either a mean annual temperature of 18 °C, or a mean temperature of 0 °C or -3 °C in the coldest month, so that a location with a "BW" type climate with the appropriate temperature above whichever isotherm is being used is classified as "hot arid" ,and a location with the appropriate temperature below the given isotherm is classified as "cold arid“.

In some instances, an area may experience more than 250 mm of precipitation annually, but is considered a desert climate because the region loses more water via vapor transpiration  than falls as precipitation (Tucson , Arizona and  Alice Springs, northern territory are examples of this).

WATER AVAILBLITY IN DESERT

Search in tree hollows. Decaying or dead trees may contain water inside the trunk. To reach into small holes, tie a cloth around a stick and fit it through the hole to absorb water.•Insects entering a hole in the tree may be a sign of water.

Look for water around and under rocks. Rocks slow evaporation, so dew or rainwater may linger around them a little longer. Turn over half-buried stones in the desert just before dawn and dew may form on their surface. (This works because the base of the stone is cooler than the surrounding air.)

ANIMALS OF DESERT

Desert Iguan DESERT TORTOISE

Desert Iguana

Dromedary Gerbil

HEDGEHOG HORNED LIZARD

VEGETATION OF DESERT

Organ Pipe Cactus Saguaro

Barrel Cactus Ocotillo Cactus

Totem Pole Cactus Pincushion Cactus

PLANTS OF DESERT

Ocotillo

Yucca

Creosote Bush Brittlebush

Succulents Creosote Bush

THANKS