Biomes – group of ecosystems that have the same climate and dominant communities

Examples: Arizona desert organisms can tolerate Tolerance – Ability to survive and reproduce under conditions that differ from their optimal conditions Examples: Arizona desert organisms can tolerate temperatures from blistering hot to below freezing

Biomes and Climate Microclimate – Climate diagram (or climatogram) (pg. 98;Fig.4-10) –diagram that shows average temperature and precipitation at a given location during each month of the year Chihuahuan Desert Climatogram

B. The Major Biomes Each biome is defined by a unique set of abiotic factors – particularly climate - and a characteristic assemblage of plants and animals Tropical Rain Forest Desert Temperate Grassland Temperate (Deciduous) Forest Boreal Forest (or Taiga) Tundra Tropical Savanna

Tropical Rainforests - biome in which the temperatures stay warm and rain falls year round Found: equatorial regions (0o) Abiotic factors: warm temperatures year round rainfall year round (200-400 cm/yr) **thin, nutrient-poor soil (organic matter decomposes rapidly) Home to MORE species than all other land biomes combined!

Dominant plants: Broad-leaf evergreens, ferns, large, woody vines, orchids, bromeliads

Desert – biome that receives less than 25 cm of rainfall per year Found: 30o N & S of equator and leeward side of mountains Abiotic factors: LOW precipitation extreme temperature variations from day to night

Desert life MUST adapt to very low precipitation

Armadillo Lizard Kit Fox Kangaroo rat

Grasslands – biome consisting of vast area covered with grasses and small leafy plants Found: interior portions of continents Abiotic factors: cold winters, warm summers moderate rainfall (25-75 cm/yr) ****Deep, rich soils

Dominant plants: perennial grasses, herbs and flowers

Animals: prairie dogs, rabbits, coyotes, ferrets, antelope, birds

Temperate Deciduous Forest – biome characterized by changing seasons and leaf fall Found: E. U.S., SE Canada, most of Europe, parts of Japan, China and Australia Abiotic factors: hot summers, cold winters year-round precipitation (75-150 cm/yr) fertile soils

Dominant plants: broad leaf deciduous trees (maples, oaks), flowering ground plants, ferns and moss

Dominant Animals: deer, black bears, squirrels, raccoons, skunks, songbirds

Taiga (or Boreal Forest) – biome dominated by great coniferous (cone-bearing, needles) forests Found: across northern N. America, N. Europe, N. Asia Abiotic factors: long, cold winters and mild summers moderate precipitation (50-100 cm/yr) soil - acidic, poor

Dominant plants: coniferous forests (pines, spruces, firs)

Animals

Tundra – northernmost land biome covered by mosses, lichens and grasses and characterized by permafrost Abiotic factors: Permafrost – layer of permanently frozen subsoil “Frozen desert” 10-15 cm/yr precipitation Short, soggy summers/long cold dark winters Poorly developed soils

Dominant plants: lichens, mosses, perennial grasses, stunted shrubs Arctic moss Arctic willow Tundra Reindeer lichen

Animals Lemming Snowy Owl Tundra swans Mosquito larva Polar bear Caribou (reindeer) Arctic fox

3rd T.L. 2nd T.L. 1st T.L.

Savanna - characterized by perennial grasses, spotted with isolated trees and/or small groves of trees Abiotic factors: warm temperatures year round seasonal rainfall (wet and dry)

Animals - Herds of grazing animals (zebras, giraffes, antelopes, elephants), large carnivores (lions, cheetahs, hyenas) Dominant plants: Tall, perennial grasses spotted with isolated trees

Savanna Food Web

Other biomes include: Tropical Dry Forest – occurs where rainfall is highly seasonal and temperatures warm year round; during dry season trees drop leaves to conserve water Found: parts of Africa, S. and Central America, Mexico, India, Australia and tropical islands

Temperate Woodland and Shrubland –characterized by a semi arid climate and a mix of shrub communities (chaparrel) and open woodlands Found: West coasts of North and South America, around the Mediterranean, S. Africa and Australia

Northwestern Coniferous Forest (Temperate Rainforest) Mild, moist air from Pacific provides abundant rainfall and mild temperatures Found: Pacific coast of NW U.S. and Canada, from Northern California to Alaska

C. Other Land Areas 1. Mountain Ranges – abiotic and biotic factors vary with elevation As you move up in elevation, temperature becomes colder and precipitation increases

Polar Ice Caps – Border tundra and are cold year round Arctic Ocean – covered with sea ice Polar bears, seals, insects and mites Antarctica – Covered by layer of ice nearly 5 km thick in some places Penguins and Marine mammals