Desert Ecosystem

1. Desert Ecosystem By Naisha Gandhi 9Yi 5

2. Introduction Deserts are dry lands with with very less annual precipitation. Annual rainfall is usually less than 25 cms and not uniform throughout the year. It may be found in a cold region or a hot region contrary to the belief that deserts are always very hot. The soil is coarse and sandy type. There are sand dunes and shifting sand in a desert. The hot deserts have high day temperature and nights are cold. The four main types of desert include hot and dry deserts, semi-arid deserts, arid deserts, and cold deserts. 1. 2. 3. 4. 5. 6. 7.

3. Hot and dry deserts 1. 2. In hot and dry deserts,, the temperatures are warm and dry year-round. Some famous arid deserts include the Sahara Desert that covers much of the African continent and the Mojave Desert located in the southwest of the United States. Sahara Desert Mojave Desert

4. Semi arid Deserts Semi-arid deserts are a bit cooler than hot and dry deserts. The long, dry summers in semi-arid deserts are followed by winters with very little rainfall. Summer temperatures are between 21-27°C on average, normally not going above 38° C. During the evenings, temperatures are cool, around 10° C. Cool nights help plants and animals by reducing moisture loss from transpiration, sweating and breathing. Just like a regular hot desert, rainfall in a Semiarid desert is very low, 2-4 cm yearly. Semi-arid deserts are found in North America, Greenland, Europe, and Asia. 1. 2. 3. 4. 5. 6. Thar Desert Namib Desert

5. Arid Deserts The cool winters of coastal deserts are followed by moderately long, warm summers. The average summer temperature ranges from 13-24° C; winter temperatures are 5° C or below. The maximum annual temperature is about 35° C and the minimum is about -4° C. In Chile, the temperature ranges from -2 to 5° C in July and 21-25° C in January. The average rainfall measures 8-13 cm in many areas. The maximum annual precipitation over a long period of years has been 37 cm with a minimum of 5 cm. 1. 2. 3. 4. 5. 6. Atacama Desert in Chile

6. Cold Deserts 1.These deserts are characterized by cold winters with snowfall and high overall rainfall throughout the winter and occasionally over the summer .2. They occur in the Antarctic, Greenland and the Nearctic realm. 3.They have short, moist, and moderately warm summers with fairly long, cold winters. 4. The mean winter temperature is between -2 to 4° C and the mean summer temperature is between 21-26° C. 5. The winters receive quite a bit of snow. 6. The mean annual precipitation ranges from 15-26 cm. 7. Annual precipitation has reached a maximum of 46 cm and a minimum of 9 cm.

7. Cold Deserts Pictures Torgersen Island in Antarctica is a cold desert. Spiti Valley Desert in Himalayas in northern Himachal Pradesh Antarctica Desert

8. Abiotic components of the desert 1. The abiotic components consist of the atmospheric gases , water , temperature and soil which are virtually devoid of organic matter. Most deserts get around 10 inches of rain per year. Groundwater exists far below the surface and plants have adaptations like incredibly long roots to reach it. The desert remains exposed to sun during most hours of the day. Temperatures vary greatly in the desert depending on location and time of day . With no water to store heat from the day, the temperature fluctuates immensely. 2. 3. 4. 5. 6. Very little rainfall Soil is dry.

9. Biotic components of the desert Producers -cacti Primary consumers - burrowing and nocturnal rodents , reptiles , insects , arachnids like scorpions and spiders , camels , wild ass , foxes , kangaroos , rats , squirrels etc. Secondary consumers - lions , cheetahs , foxes , wolves Tertiary consumers - lion , cheetahs Decomposers - few bacteria and fungi

10. Biotic components and food web pictures Food web

11. Adaptations in plants of a desert

12. Adaptations in animals of a desert

13. Threats to a desert

14. Desert Youtube Video Link https://www.youtube.com/watch?v=l3iqOBaCsMs