Terrestrial biomes

I. Biomes: areas that have distinctive

climates and organisms

Tropical Rainforest

Tropical Rainforest

once, 20% of earth; now 7%

exist around equator, so strong sunlight and consistent climate.

Tropical Rainforest

humid, always warm, never freezes, lots of rain (100-400 in. a year = 250-1000 cm/yr)

Tropical Rainforest

Has poor soil. So how do many species of plants thrive?

answer: rapid decay of plants and animals constantly returning nutrients to the soil

plants grow in layers (strata) for sunlight. Lots of light at canopy; little at bottom. Plants on forest floor often have huge leaves.

animals are often poisonous or camouflaged

Temperate Rain Forest

occur in North & South

America, Australia, & New Zealand

Temperate Rain Forest

cool & humidMild winters and summers for latitude

70 – 200 inches of rain per year (150 – 500 cm)

Temperate Rain Forest

Only a few species of lush evergreen and deciduous trees on windward slopes

Redwoods – tallest trees on earth

Huge ferns, thick undergrowth

Temperate Rain Forest

Numerous bird and mammal species – raccoons, gray wolf, white-tailed deer, bears, badgers, wild pigs, etc.

Temperate Deciduous ForestsLeaves turn

colors. Trees shed

leaves each fall.

Temperate Deciduous Forestsexist b/t 30 degrees & 50 degrees north latitude, so seasonal variation

Temperate Deciduous Forests

30 - 100 inches

Precipitation

(75-250 cm/yr)

soil rich & deep. Why?

rain causes rapid decomposition of leaves

forests grow in layers

migratory birds ; hibernating animals

Taiga: northern coniferous forest just below Arctic

Circle

Taiga

long, cold winters

precipitation = snow

constant daylight in summer

Taiga

conifer trees: needle-shaped leaves (retain water, acidic)

Taiga

soil forms slowly, is acidic; few plants on ground

Taiga

migrating birds, burrowing and camouflaged animals

Tropical Savanna

Tropical Savanna

near equatorvery little rain - less than 6 months of the year (4 –70 inches)

Tropical Savanna

plants: long underground roots to survive fire and dry season, perennials;

- thorny plants so animals won’t eat

Tropical Savanna

Migratory herbivores follow rains- different herbivores eat plants of different heights.

Tropical Savanna

Contains the largest number of grazing animals

Tropical Savanna

predators follow

mostly large land animals

Grassland & Prairies

Temperate Grasslands & Prairies

Rainfall – 25 – 88 cm/year (10 – 35 in/yr)

Sizzling temperatures in summer

30º - 50º N latitudebuffalo

Temperate Grasslands & Prairies

Plant Adaptations- Root systems of plants form dense mats to survive drought and fire and hold the soil in place.- Few trees because of the drought, fire and constant wind.

Temperate Grasslands & Prairies

Animal Adaptations- buffalos have thick coats to withstand the cold winters

- prairie dogs & owls live in underground burrows to protect them from fire, elements and predators

Deserts

Desertsreceive less than 10

in. precip/yr (25 cm/yr) extreme temp flux!

Dry winds

Deserts

soil rich in minerals, but poor in organic matter. Why?

Desertsans: not enough water to aid in decomposition.

Desertsplants: succulents :thick stems & leaves to store water -

Desertsspiny & thorny

underground bulbs or wide root systems

Deserts

animals:dry, scaly skin

Desertssome estivate (bury themselves in the ground & sleep through the dry season)

Desertsmany nocturnal

Kangaroo rat

Tundra

Tundra

North of the Arctic Circle

Tundra

biome w/o trees, grasses & shrubs grow in permanently frozen soil (permafrost)

Tundra7 – 40 inches of rain/yearOnly 2 or 3 months above freezing

Long and cold winterBrief cool summer

Tundraplants:mosses & lichens (can grow w/o soil)

Tundrawide, shallow roots anchor plants against wind

animals:migratorycamouflagethick coats

Tundra