Tundra The largest biome Characterized by low rainfall and low temperatures (Temp -26c to 12c Shallow soil Permafrost –Frozen ground 3 feet or more below the surface. –In winter all the ground if frozen Short season 2 month and slow growing Precipitation=less than 25 cm but most of the time the water is frozen and there Is little evaporation

Primary producers Slow growing and low to the ground. –Going north or up = Shrubs = lowest/south Grasses lichens = highest/north

Animals Large animals where there volume is greater than surface area –Moose –Polar bears –Caribou/reindeer Smaller animals –Artic fox

Threats Disruption Road construction Global warming –Decreases in habitat Sea rising Increasing CO2 contribution

Taiga Biome Characteristics

Low diversity –Only 20 major species Formed from low coniferous cone bearing trees (evergreen) –Pines, Furs and Spruces Cold climates and high altitudes -10C to14C Precipitation= cm Acidic thin soil minimal under story. Cold harsh winters with little to no usable water

Animals Moose, Voles, Foxes, Deer, Migratory Birds (visiting for the summer), Carnivorous Birds.

Facts Contain some of the largest wilderness areas world wide. Once, during the ice ages formed a continuous band of forest from Europe to Canada (there was a land bridge from Russia to Alaska.

Threats Insects –Pine Beatles kill the pines –Spruce bud worm Fires –These forests burn every 90 years. -Limiting forests to no taller than 30 feet

Temperate Deciduous Forests Pronounced seasons Broad leaf plants which lose their leaves. Warmer winters than taiga Temp =6C to 28C And wetter precipitation= cm Most major cities in the world are in this biome. Large amounts of fallen leaf matter make thick nutrient rich soil. Winters are short and trees may become dormant for several months.

Organisms Less diverse than tropical forests but more diverse than taiga –Deciduous trees and dense underbrush –Oak, Maple, Ash, Burch, Hemlock, –Smaller mammals' Deer, rabbits, squirrels, black bear, migratory birds.

Threats Population growth –Urban Sprawl –Logging…… –Introduced species/invasive

Tropical forests The highest amounts of diversity: of the 300 thousand plant species world wide 200 thousand may be found in tropical forests. 1/5 of the worlds species are contained in tropical rainforests Consistent warm temperatures all year. Temp =20C to34 c and rain fall= cm Soil is thin and sandy. –All the nutrients are in the trees. –Many plants Have a beneficial relationship with nitrobacter forming mycorrhizae

Biota Vegetation forms stratified layers called canopies. Plants live on the trees=epiphytes The tallest are broad leaf bearing trees which do not lose there leaves. Animals include kopibarra, sloths

Desert Biome Largest range of temperature 7C and 38C Dry less than 25 cm of rain. Soil sandy and poor Plants have adapted to storing water. Waxy Leaves Animals burrow/ nocturnal / large surface areas. It takes a long time for species to grow.

Deserts 2 types –Tropical deserts Sahara –Temperate deserts The great American desert Both have the largest temperature changes of any biome. Low diversity

Chaparrel Temperature change is seasonal-mild 30f to 100f Sunny High diversity Rain=10-17 in Highly flammable in the summer. Burns 25 years High population density.