BiomesChapter 6 page 152

A. What is a biome?1. Biome – large region characterized by specific

climates, plants, and animals

2. Biomes and Climatea. Climate determines plant lifeb. Climate – weather condition over a long period

of time1)Temp, precip, humidity, and winds2)Temp. and precip. are most important for

determining climate

c. Temperature and Precipitation

1) Organisms adapt to survive certain temperature ranges

2) Growing season affects types of plants possible

3) Larger organisms need more water

a) Determines if there are trees or shrubs

b) Are there going to be shrubs or cacti

d. Latitude and Altitude

1) Latitude – distance north/south of equator

2) Altitude – height above sea level

3) Climate gets colder as latitude and altitude increase

4) Vegetation change with latitude and altitude which means biome changes as well

3. Biomes and vegetation

a. Biomes described by their vegetation

b. Vegetation determines organisms that live there

c. Organisms have adaptations which allow them to live in a certain biome

B. Forest Biomes1. Tropical Rain Forests

a. Place of greatest plant and animal biodiversityb. Located on a “belt” by the equatorc. Regulate climate, N, O, and C cyclesd. 6.5ft – 14.8ft of rain/yre. Maintain constant temperature year round

f. Nutrients

1) Found in the biomass NOT the soil

2) Warm wet temperatures allow

decomposers to thrive

3) Plants immediately take up

nutrients from decomposers

4) Areas used for farming – terrible idea

g. Layers of rain forest

1) Emergent Layer – top layer of trees w/direct line to sunlight

2) Canopy

a) Absorbs most (95%) of sunlight

b) Upper and lower canopy

c) Most animals live here

3) Understory

a) Below canopy

b) Contains plants adapted for

shade

c) Shorter plants w/large broad

leaves for catching sunlight

h. Threats to Rain Forests

1) Used to cover 20% now

it is bout 7%

2) Habitat destruction – land

inhabited by organisms is

destroyed or altered

2. Temperate Forests

a. Temperate rain forest

1) North America, Australia, and New Zealand

2) Large amounts of precip, high humidity, and moderate temperatures

3) Mostly conifers

4) Pacific Northwest is North America’s only location

a) Pacific ocean helps

b) Mountains help

3. Temperate Deciduous Forest

a. Deciduous trees – trees which lose their leaves

b. North America, Europe, and Asia

c. 30° – 50° North latitudes

d. Temp range is extreme (95°F + to below freezing)

e. Growing season is 4-6 months

f. Winter gives slower decomposition rates and increases soil nutrients

g. Plants

1) Trees – maple, oak, birch

2) Trees provide a canopy

3) More light reaches floor for ferns, mosses, and herbs

4) Plants go dormant during the winter

h. Animals

1) Squirrels, bears, deer, birds, etc.

2) Most birds are migratory

3) Some animals hibernate

4) There are adapted to extreme

temperature ranges

4. Taiga

a. Northern coniferous forest

b. Winters 6-10 months

c. Average temps below freezing

d. Plants

1) Conifers – trees with needles and seeds with cones

2) Not many plants on forest floor

e. Animals

1) Many lakes and swamps

2) Birds which migrate south at winter

3) Jumping mice, showshoe hares,

lynxes, wolves, foxes

4) Many have brown fur in summer

and white in winter

C. Grassland, Desert, and Tundra Biomes1. Savannas

a. Tropical biome dominated by grasses, shrubs, and small trees

b. Has wet and dry seasonsc. Plants

1)Can survive long periods w/o rain2) Shallow widespread root systems3) Many have thorns

d. Animals

1) Many migrate with rains

2) Give birth during wet seasons b/c of abundance of food

3) Elephants, gazelles, rhinos,

giraffes, cheetahs, lions, hyenas

2. Temperate Grasslands

a. Large areas in the middle of continents with moderate rainfall

b. Not enough rain for trees

c. Prairies

d. Plants

1) Dry out in summer and can start fires

2) Grasses and wildflowers

3) Roots systems are dense which can survive drought and fire

4) Most fertile soil in the world

5) Experience hot summers and cold winters

e. Animals

1) Pronghorn antelope, bison, badgers, prairie dogs, etc.

2) Lots of grazers

f. Threats

1) Farming and overgrazing

2) Erosion

3) Converted into farmland

Prairie in the past

• Mountains limit rainfall

• Moving east rainfall increases so there are

more trees

3. Chaparral

a. Temperate shrubland biome

b. Moderately dry, coastal climates w/little to no rain in the summer

c. Plants – evergreen shrubs

d. Animals – lizards, chipmunks,

mule deer

4. Deserts

a. Widely scattered vegetation and have very little rain

b. Very extreme temperature ranges in 24 hrs (104°F to near freezing)

c. Near mountains – rain shadow effect

d. 30° N and 30° S – Hadley cells

e. Plants

1) Adaptations for conserving water

2) Very shallow roots which are widespread

3) Thorns

f. Animals

1) Dry, scaly skin

2) Most nocturnal b/c it’s cooler

5. Tundra

a. Northern arctic regions

b. Too cold for trees

c. Permafrost – deeper layers of soil which remain frozen year round

d. Contains bogs in summer

e. Most fragile biome b/c of simplified food chains

f. Plants

1) Growing season is short

2) Grow close to ground to avoid wind

and absorb heat

g. Animals

1) Migratory birds

2) Insects and worms

3) Caribou, wolves, moose, elk, etc.

h. Threats

1) Damaged easily and slow to recover

2) Oil exploration and extraction

3) Pollution