Transcript Regional Effects

Ecology: Biomes
Earth’s Diverse Ecosystems
Biomes
• Major regional land ecosystems
defined by climate (temperature and
precipitation) and vegetation type
• Climate is influenced by
– Sun
– Rotation and Tilt of Earth
– Regional Effects
Angle of Incident Sunlight
Affects Temperature
Sunlight strikes the earth at a steeper angle and over a
smaller area at the equator. Temperatures are highest at
the equator and decline at latitudes toward the poles.
Earth’s Tilt Affects the Seasons
Short days;
Long nights;
Winter
Long days;
Short nights;
Summer
Reversed when
on the other
side of the Sun
Air Currents and Climatic Regions
•Warm air rises near
equator (0o)
– Cools and releases rain
– Draws air from
surrounding area
•Rising air travels North
and South from equator
– Dry, warm air descends at
30° both North and South
•Cycle is repeated again
at 60° and 90° latitudes
Wind Is Influenced by Temperature
and the Earth’s Rotation
•Earth’s rotation
bends paths of
air moving in
N-S direction
– Air moving toward
equator turns west
– Air moving away
from equator turns
east
– wind belts named
for direction they
come from
Low
(Altitude)
High
Regional Effects:
Influence of Elevation on Temperature
Equatorial
(Latitude)
Polar
Regional Effects: Rain Shadow
Average Annual
Precipitation (cm)
150
Altitude (m)
5000
4000
100
3000
2000
50
1000
0
West
East
Precipitation in the Sierra Nevada Mountains
0
Regional Effects: Ocean Circulation Patterns
N. Pacific
Gyre
S. Pacific
Gyre
N. Atlantic
Gyre
S. Atlantic
Gyre
Sun influences ocean currents
Applying Your Knowledge
1.
2.
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4.
5.
Earth’s Tilt and Rotation Around Sun
Rain Shadow
Elevation
Ocean Circulation Patterns
Angle of Incidence of Sun’s Rays
Which one best explains:
A. dry conditions on the east side of the
Sierra Nevada mountain range?
B. winter weather in NE United States?
C. warm temperatures at the equator?
The Distribution of 11 Biomes
High
(Temperature)
Low
Rainfall and Temperature
Affect Biome Distribution
Dry
(Rainfall)
Wet
Tropical Rain Forest
Tropical Rain Forest Biome
• Climate
– Warm temperatures
– Large amounts of
rainfall
• Plant Life
– Tall, broad-leaved
evergreen trees
– Competition is the
limiting factor for
plant growth
– Greatest diversity of
species on the planet
• Location
– Along the equator
Observing the Costa Rican Rain Forest
Savanna
Savanna
• Climate
– Short rainy season
– Long, severe
droughts
• Plant and Animal
Life
– Grass with scattered
clumps of trees
– Large mammals
• Location
– Along the edges of
tropical deciduous
forests
Deserts
Desert
• Climate
– Less than 10 inches of
annual rainfall
– Temperature extremes
• Plant Life
– Widely-spaced
vegetation
– Wild flower blooms
• Location
– 20-30o North and
South latitudes
– In rain shadows of
mountain ranges
Chaparral
Chaparral
• Climate
– Mild rainy winters (30”)
– Long, hot, dry summers
• Other factors
– fire
• Plant Life
– Small trees
– Spiny shrubs
• Location
– Coastal regions that
border on deserts
Grasslands
• Climate
– 10-30 inches of
rainfall in summer
– Snow in winter
• Other factors
– Periodic droughts
– Frequent fires
– Grazing animals
• Plant Life
– Grasses
– Trees found only
along rivers
• Location
– Centers of continents
Grassland
Temperate Deciduous Forests
Temperate Deciduous Forest
• Climate
– 30-60 inches of rainfall,
most during summer
– Cold winters
• Plant and Animal Life
– Layered vegetation: trees,
shrubs, wildflowers
– Deciduous trees: lose leaves
in cold, dry weather
– Abundant animal species
• Location
– East of grasslands in
North America
– Western Europe
– East Asia
Taiga
Taiga
• Climate
– Short growing season
– Long, cold winters
• Plant and Animal Life
– Evergreen conifers
– Limited species diversity
• Location
– North of grasslands
and deciduous forests
(50o-65o N)
– Mountainous areas
Tundra
• Climate
– Long cold winters
– Short cool summers
– 10 or fewer inches of
precipitation
• Other factors
– Permafrost limits
root growth
• Plant and Animal Life
– Grasses
– Perennial flowering plants
– Breeding area for birds
• Location
– Bordering Arctic Ocean
Tundra
And the Very Last Set of Hints….
1.
2.
3.
4.
5.
Desert
Taiga
Temperate Deciduous Forest
Tropical Rain Forest
Tundra
Which biome is characterized by:
A. trees that lose their leaves in cold
weather?
B. permafrost?
C. coniferous forests?