Desert Biome Location:

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North America: Sonoran, Chihuahua, Mojave, Great Basin.
Australia: Great Victoria, Great Sandy.
South America: Patagonian and Argentinian Deserts, Atacama region.
Arabian Peninsula: extends to Syria and Israel.
Africa: Sahara, Kalahari, Danakil.
Cold deserts in the Antarctic and Central Asia.

Biotic Factors:

Many plants and animals exist in the desert, contrary to popular opinion that deserts are desolate and sustain little life. Scorpions, coyotes, snakes, spiders, lizard, and cacti are just a few of the biotic factors.

Abiotic Factors:

Sand: The soil of a desert is maily comprised of vast sections of sand spanning over miles of land. The sand is dry and not mineral rich, enabling very little plant life to thrive on its foundation. Sometimes in cold deserts, moss and grass will join sand to make up the land and create very mineral-rich soil.
(Lack of) Moisture: Precipitation of deserts vary. Depending on if the desert is dry, semiarid, coastal, or cold, the amount of rainfall is different. Hot and dry deserts yield usually only yield less than 10 inches or rain per year. Cold deserts may not receive much more, but it could be in the occasional form of snow as opposed to rain.
Temperature: Hot/ dry deserts are located very near to the equator and have a very warm temperature range: 20-25° C
with an extreme of about 45 degrees celcius. Cold deserts, like in the Antarctic and Central Asia, are different from hot deserts in that their temperatures drop down much more in winter. Cold deserts' temperatures range from from -2 to 4° C in winter and in the summer 21 to 26° C.

Plant Adaptions:

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  • Some plants, called succulents (cacti and stonecrops), store water in their stems or leaves;
  • Some plants have no leaves or small seasonal leaves that only grow after it rains. The lack of leaves helps reduce water loss during photosynthesis. Leafless plants conduct photosynthesis in their green stems.
  • Phreatophytes like sagebrush have Long root systems spread out wide or go deep into the ground to absorb water;
  • Some plants have a short life cycle, germinating in response to rain, growing, flowering, and dying within one year. These plants can evade drought.
  • Leaves with hair, like the desert yellow fleabane, help shade the plant, reducing water loss. Other plants have leaves that turn throughout the day to expose a minimum surface area to the heat.
  • Spines to discourage animals from eating plants for water;
  • Waxy coating on stems and leaves help reduce water loss.
  • Flowers that open at night lure pollinators who are more likely to be active during the cooler night.
  • Slower growing requires less energy. The plants don't have to make as much food and therefore do not lose as much water.

Animal Adaptions:

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-Dissipate heat: long appendages (legs, ears, etc.), or small "bodies" radiate heat of the desert. An example of this would be the Fennec Fox.
-Tolerate Hyperthermia: some animals can survive body temperatures that would be dangerous to humans. An example of this would be the antelope squirrel.
-Survival without water: some animals can go without water for a very long time, like the camel. It stores large amounts of water with the help of the hump on its back, an adaptation that allows it to stay hydrated even in the driest deserts.