Biomes Biomes Biomes • Community characterized by by qingyunliuliu

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• Community characterized by dominant
  vegetation and prevailing climate
  – Climate=avg. temp. and avg. precipitation
  – General trend: as altitude and latitude
    increases, temp. and precipitation decreases
             Arctic Tundra
• No match in southern hemisphere
• Extreme northern latitudes (alpine tundra-
  high elevations; above tree line on
    Arctic Tundra Characteristics
•   Long, harsh winters/short summers
•   Little to no precipitation (driest place on earth)
•   Nutrient poor soil, little organic matter
•   Permafrost-permanently frozen ground
    – Poor drainage, soil gets waterlogged
    – Creates bogs in summer
    – Roots cannot penetrate the ground (no tree species)
• Little diversity, little primary productivity
• Regenerates VERY slowly after disturbance
           Tundra Plants
• Mosses
• lichen
              Tundra Animals
•   Lemmings
•   Weasels
•   Voles
•   Arctic fox-(video nat. geo)
•   Arctic hare
•   Snowy owl
•   Musk oxen
•   Migrators-caribou/birds
Tundra Animals
        Tundra Adaptations
• Plants-wax coated leaves, underground as
  bulbs to over-winter, dehydrate to prevent
  frost damage
• Animals-thick coats and fur, feathers,
  small bodies and extremities to prevent
  heat loss
      Threats to the Tundra
• Climate change
• Oil production
• Video-teacher’s domain
 Taiga (TIH-ga) Coniferous Forest
• Just south of tundra
• Stretches across N. America and Eurasia
        Taiga Characteristics
• Winters are severe and cold
• Short growing season
• Not much precipitation
• Soil is acidic, nutrient poor (partially
  decomposed pine needles)
• Patchy permafrost
• Ponds, lakes carved by glaciers
             Taiga Plants
• Coniferous evergreens (pine trees)
• Spruces, balsam fir
• **extensive logging here**
              Taiga Animals
•   Caribou
•   Wolves
•   Bears
•   Moose
•   Lynx
•   insects
Taiga Animals
         Taiga Adaptations
• Needles are adapted to prevent water/heat
  loss (less surface area)
• Keeping needles all year takes full
  advantage of available sunlight
      Temperate Rain Forest
• NW coast of N. America (Seattle),
  southern S. America
       Temperate Rain Forest
• High precipitation, condensation from
  coastal fog
• Coniferous forest (pine trees)
• Temp. modified by ocean (mild
  winters/cool summers)
• Nutrient poor soil
• High organic content, but decomposition is
  slowed by cool weather
       Temperate Rain Forest
• Special, complex ecosystem; old-growth
  forest, never been logged and only a small
  fraction remains
• VERY stable
• Includes many endangered or threatened
  species that only live here
    Temperate Rain Forest Plants
•   Large evergreens
•   Douglas fir
•   Hemlocks
•   Red cedar
Temperate Rain Forest Animals
•   Eagles
•   Elk
•   Mule deer
•   Amphibians/reptiles
•   Wood rats
•   Spotted owl
    Temperate Deciduous Forest
•   This is where we live!
•   Hot summers/cold winters
•   Precipitation 30-50 inch/yr
•   Topsoil is rich in organic matter, lower
    layers mostly clay
      Temperate Deciduous Forest
•   Oak
•   Hickory
•   Maple
•   Birch

• **lose leaves annually** (Deciduous)
      Temperate Deciduous Forest
•   White-tailed deer
•   Bears
•   Birds
•   Coyotes
•   Raccoons
•   skunk
Temperate Deciduous Forest
  Temperate Deciduous Forest
• Worldwide these forests have been
  cleared for farming, logging, cities
• Where they have regenerated many
  organisms have returned
    Temperate Deciduous Forest
• Plants that lose leaves are dormant over
  the cold winter to survive drought and cold
 Threats to the World’s Forests
• Clearing for agriculture, grazing
• Clearing for timber, urban development
• Conversion to less biodiverse tree
      Temperate Grasslands
• Midwest U.S.
• Characteristics:
  – Hot summers/cold winters
  – Precipitation uncertain (10-30 in/yr)
  – Rich organic soil (that’s why there are a lot of
  Temperate Grassland Plants
• Dominant vegetation-grasses
• Only a few trees close to rivers/streams
• Wildfires frequent
    Temperate Grassland Animals
•   Prairie dogs
•   Snakes
•   Rodents
•   Foxes
•   Black-footed ferrets
•   Hawks
•   Insects
•   Bison
•   Grouse (birds)
Temperate Grassland Animals
      Threats to Grasslands
• Conversion to cropland
• overgrazing
•   Coast of California
•   Characteristics: thin soil, unfertile
•   Long, hot dry summers/mild, wet winters
•   **Frequent fires to regenerate plants
          Chaparral Plants
• Evergreen shrubs (short, drought
• Adaptations: hard, leathery leaves to
  prevent water loss
• Plants grow best after fire
        Chaparral Animals
• Wood rats
• Mule deer
• lizards
• Fires burn expensive homes, but letting
  vegetation build up causes severe fires
  and clearing vegetation causes mud slides
  in winter
• Both cold (temperate) and hot (tropical)
• Characteristics:
  – Low water vapor content results in extreme
    hot and cold temps
  – Very low precipitation less than 10 in/yr
  – Sparse vegetation so soil is low in organic
    matter; very high mineral content (amounts so
    high it can be toxic)
  – Perennials: live longer than one year and
    annuals live one year, happens after rain
             Desert Plants
• Xerophytes: cacti, saguaro, aloe vera
• Adaptations: reduced water loss because
  little or no leaves (photosynthesis happens
  in the stem), very deep roots or shallow
  roots that are very wide ranging, equipped
  with thorns, spines, or toxins to resist
  grazing pressure
Desert Plants
             Desert Animals
•   Jack rabbit
•   Fennec fox
•   Lizards
•   Snakes
•   rodents
Desert Animals
   Desert Animal Adaptations
• Large extremities for heat loss
• Small bodies
• Take cover during the day and forage at
• Obtain water from plants (dew)
• Concentrated urine, dry feces
          Desert Disturbances
•   Large desert cities
•   Off road vehicles
•   Storage of toxic chemicals
•   **very slow to recover**
 Savanna (Tropical Grassland)
• Tropical grassland
• Characteristics:
  – Low rainfall or seasonal rainfall with long periods of
  – Little temp. change year-round
  – Low in essential nutrients due to leaching
  – Rich in aluminum because aluminum is leach
    resistant (can become toxic)
  – Dominant vegetation is grasses with scattered trees
           Savanna Plants
• Acacia tree
• Adaptations:
  – Thorns to reduce grazing
  – Extensive underground roots to survive
    drought or fire
Savanna Plants
          Savanna Animals
• Lions
• Cheetahs
• Giraffes (ungulates-hooved animals),
• Elephants
• Adaptations: migrate to find water
Savanna Animals
        Tropical Rain Forest
• Central/South America, SE Asia
• Characteristics:
  – Warm temp. year round
  – Daily precipitation (80-180 in/yr), mostly
    recycled water from transpiration
  – Ancient, highly weathered, mineral poor soil
  – Little organic matter in the soil because
    decomposition happens quickly and reuptake
    happens quickly
         Tropical Rain Forest
• Characteristics continued
  – Minerals and nutrients are tied up in living
    organisms rather than the soil
  – Highly productive (a lot of photosynthesis)
  – Greatest biodiversity of all biomes
   Tropical Rain Forest Plants
• Broadleaf evergreens (large leaves, all
• Epiphytes (plants that grow on other
  plants-mosses, lianas (woody vines)
• Adaptations:
  – Leaves are broad to capture sunlight, radiate
  – Root mats catch and absorb all nutrients
    released by decomposers
Tropical Rain Forest Plants
    Tropical Rain Forest Animals
•   Insects
•   Amphibians
•   Sloths
•   Monkeys
•   Macaws
•   Ocelots
•   Adaptations:
    – Many different niches so decreased competition
       • Some animals never walk the ground
       • Adapted to certain parts of the canopy
Tropical Rain Forest Animals
Tropical Rain Forest Stratification
     Threats to the Rainforest
• As human population grows, expansion
  into rainforests-demand for land/resources
  may be the end of the rainforest in this
• Some species not identified yet
  – Could be medicines or cures for diseases

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