Biomes - Tundra & Desert

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The different types of land are known as biomes and are divided into four classifications.

Tundra

Tundra is a wide-open space of land that is the coldest of the biomes. The University of California’s Museum of Paleontology has noted that tundras are known for “frost-molded landscapes, extremely low temperatures, little precipitation, poor nutrients and short growing seasons.” This makes a tundra a very difficult place to live in due to its harsh weather conditions and poor food supplies. Arctic and alpine are the two types of tundras on earth. Alpine tundra refers to tundra located above the treeline, although it can have sparse vegetation of other kinds. Arctic tundras do have vegetation and can sometimes have rainfall.

Characteristics of Tundra

1. Extremely cold climate
2. Low biotic diversity
3. Simple vegetation structure
4. Limitation of drainage
5. Short season of growth and reproduction
6. Energy and nutrients in the form of dead organic material
7. Large population oscillations

Desert

Deserts generally fall into hot/dry and cold categories. Hot/dry deserts have sparse vegetation, and only animals that can adapt to living in extremely hot temperatures with minimal water can survive there. Most animals in a hot/dry desert must burrow to escape the tremendous heat, which can reach up to 120 degrees Fahrenheit in the daytime. In cold desert climates, the temperatures are much cooler. Animals that live there must burrow to keep warm. Unlike hot/dry deserts, cold deserts have precipitation in the form of snow or rain. Temperatures drop to the low 30s (Fahrenheit) in the winter.

• hot & dry (what we typically think of with the word desert):
  • high temps
  • mostly nocturnal animals
  • very little rainfall
  • succulent plants such as aloe, prickly pears, & agaves
  • ground is mostly loose sand
• semiarid (what we see in old western movies)
  • long summers but still has a “winter” season with little rainfall
  • Cool nights in the summer/cold in the winter (this is generally how the plant life in these areas get their moisture, from the dew that forms from the drastic change in temperature)
  • ground is often gravely or rocky
  • plant life is mostly shrubs like sage, hardy grasses, & succulents
  • animals are usually things like jack rabbits, kangaroos, skunks, & reptiles
• coastal deserts
  • have moderately long, warm summers with winters quite chilly
  • fine soil with a moderate salt content
  • plants are generally brush & grasses
  • animal types vary greatly with anything from toads to coyotes to badgers to great horned owls.
• cold deserts are places like Greenland with
  • long, cold winters & short moderately warm summers
  • plenty of snow in the winters months
  • plants are usually low-lying leafy bushes & ground cover that flower in warm weather and/or produce berries
  • animals include things like deer & foxes