1. The Dessert By Stefano Pacifici

2. Dessert Locations  Major locations include: Sahara Africa, South Africa, Australia, and The Arabian Peninsula.

3. Dessert Vegetations  Palm Tress  Desert Sage  Barrel Cactus  Palm Tress  Desert Sage  Barrel Cactus

4. Average Rainfall  In Sahara, there is less than 1.5cm a year.  In the USA, there is about 25cm a year.  On average, there is no more than 10 inches of rainfall in any desert.  In Sahara, there is less than 1.5cm a year.  In the USA, there is about 25cm a year.  On average, there is no more than 10 inches of rainfall in any desert.

5. Desert Sunlight  On average, most deserts receive immense amount of sunlight throughout the day.

6. Desert Temperatures  Desert temperatures get very high during the day, around a 100 degrees.  Yet, get very low at night.  This is because they are bare and have no protection to keep them from heating up in the sun and cooling off when the sun disappears at night.  Desert temperatures get very high during the day, around a 100 degrees.  Yet, get very low at night.  This is because they are bare and have no protection to keep them from heating up in the sun and cooling off when the sun disappears at night.

7. Soil Fertility  Deserts have a low soil fertility because of their arid (little rain) soil that contains little to no nutrients.

8. Seasonal Changes  At specific times of year, nights can drop below freezing.  Also, amount of precipitation can fluctuate drastically and can come and go sporadically.  At specific times of year, nights can drop below freezing.  Also, amount of precipitation can fluctuate drastically and can come and go sporadically.

9. Limiting Factors  Low amounts of rain and high temperatures are limiting factors.  Because of the low amounts of rain, deserts have arid soil without many nutrients so not much vegetation can occur.  Low amounts of rain and high temperatures are limiting factors.  Because of the low amounts of rain, deserts have arid soil without many nutrients so not much vegetation can occur.

10. Animal Adaptations to Limiting Factors  A lot of desert animals stay deep underground in burrows where it is much cooler.  A lot of desert animals don’t need to drink, they get a lot of their water from plants.  Many animals are nocturnal, sleeping during the hot day and only coming out at night to eat and hunt.  To retain water, a lot of rodents have extra microscopic tubules to retain most of their water from urine.  Several desert animals have extra long appendages to release heat into their environment; a more effective way of evaporative cooling.  A lot of desert animals stay deep underground in burrows where it is much cooler.  A lot of desert animals don’t need to drink, they get a lot of their water from plants.  Many animals are nocturnal, sleeping during the hot day and only coming out at night to eat and hunt.  To retain water, a lot of rodents have extra microscopic tubules to retain most of their water from urine.  Several desert animals have extra long appendages to release heat into their environment; a more effective way of evaporative cooling.

11. Desert Animals  Cheetah  Naked Mole Rat  Sand Cat  Mexican Milk Snake  Coyote  Lizards  Ostrich  Llama  Cheetah  Naked Mole Rat  Sand Cat  Mexican Milk Snake  Coyote  Lizards  Ostrich  Llama

12. Plant Adaptations to Limiting Factors  Desert plants, such as cacti can activate their xerophytes, which have special abilities in retaining water.  Other plants, called Phreatophytes, have developed extremely long roots to allow them to acquire moisture better.  Dessert perennial plants often survive my remaining dormant during dry periods, then coming to lift when water becomes available.  Annual desert plants germinate right after a period of heavy rain, then complete their reproductive cycle very quickly.  Some desert plants have developed spines to prevent animals from eating plants for water.  Desert plants, such as cacti can activate their xerophytes, which have special abilities in retaining water.  Other plants, called Phreatophytes, have developed extremely long roots to allow them to acquire moisture better.  Dessert perennial plants often survive my remaining dormant during dry periods, then coming to lift when water becomes available.  Annual desert plants germinate right after a period of heavy rain, then complete their reproductive cycle very quickly.  Some desert plants have developed spines to prevent animals from eating plants for water.

13. Desert Plants  Creosote Bush  Saguaro  Desert Wildflower  Desert Marigold  Desert Lily  Orange Pipe Cactus  Elephant Tree  Desert Willow  Creosote Bush  Saguaro  Desert Wildflower  Desert Marigold  Desert Lily  Orange Pipe Cactus  Elephant Tree  Desert Willow

14. Desert Food web

15. Human Activities Affecting Deserts  Over the past century, humans have found more and more efficient ways to make the desert livable for more people.  The formation of dams, miles of water canals, and millions of air-conditioning units have resulted in the deserts becoming a comfortable environment for cities, as well as agriculture and grazing industries.  Over the past century, humans have found more and more efficient ways to make the desert livable for more people.  The formation of dams, miles of water canals, and millions of air-conditioning units have resulted in the deserts becoming a comfortable environment for cities, as well as agriculture and grazing industries.

16. Colorado River and Hoover Dam on the border of Arizona and Nevada

17. Desert Changes  Increased grazing has altered the desert plant community and agriculture.  Irrigation has altered streams, rivers, and canyons.  Invasive species have been able to come and dominate some of the landscape.  Last, the growth of cities in replacing the once desert landscape with concrete, lawns, and homes.  These have all caused nutrient availability in the soil to decrease, and moisture retention of the soil is to decrease.  Increased grazing has altered the desert plant community and agriculture.  Irrigation has altered streams, rivers, and canyons.  Invasive species have been able to come and dominate some of the landscape.  Last, the growth of cities in replacing the once desert landscape with concrete, lawns, and homes.  These have all caused nutrient availability in the soil to decrease, and moisture retention of the soil is to decrease.

18. Desert Conservation  The Salt River Project is a plan that could restore the Salt River, north of Phoenix, to its natural state. The plan involves reintroducing a small, flowing stream and desert habitat to the currently dry riverbed.