Biomes
There are 2 types:
 Terrestrial Biomes (on land)
 Aquatic Biomes (in the water)
Terrestrial Biomes
Forest Biomes:
 Tropical rain forest
 Temperate rain forest
 Temperate deciduous
forest
 Taiga
Grassland, Desert, and
Tundra Biomes:
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Savanna
Temperate grassland
Chaparral
Desert
Tundra
Chapter 6 Section 2
Forest Biomes
Objectives
 List three characteristics of tropical rain forests.
 Name and describe the main layers of a tropical
rain forest.
 Describe one plant in a temperate deciduous forest
and an adaptation that helps the plant survive.
 Describe one adaptation that may help an animal
survive in the taiga.
 Name two threats to the world’s forest biomes.
Chapter 6 Section 2
Forest Biomes
Key Terms
 Tropical rain forest
 Emergent layer
 Temperate rain forest  Canopy
 Temperate deciduous  Understory
forest
 Taiga
 Epiphyte
Biomes of the World
Forest Biomes
 Of all biomes, forest biomes
are the most widespread and
the most diverse.
 Large trees need lots of
precipitation – plentiful
rainfall.
 Temperatures range from
mild to hot.
Tropical
Rain
Forest
Tropical Rain Forest
Tropical Rain Forest
 Typically near the equator
 Help regulate world climate
and play vital role in C, N,
and O cycles
 Receive more than 200 cm of
rain annually
 Temperatures relatively
constant: between 20oC and
25oC for the entire year
Tropical Rain Forest
Nutrient cycles
 Rapid decay of organisms
so soil is thin.
 Forest floor typically not
covered with plants.
 Soil nutrients quickly
absorbed by plants.
 Runoff very clean due to rapid
absorption of nutrients by plants.
Tropical Rain Forest
Layers of Rain Forest
 Emergent layer (top) – tallest trees (60-70 m),
receive direct sunlight
 Canopy (middle) – trees greater than 30 m tall,
absorb 95% of sunlight, abundant flowers and
fruits, epiphytes
 Understory (lower level) – very little light, shorter
plants (3.5 m) adapted to shade
Emergent Layer
Bright Light
Upper Canopy Layer
Filtered Light
Lower Canopy Layer
Understory Layer
Dense Shade
Tropical Rain Forest Layers
Tropical Rain Forest
Species Diversity
 Greatest in tropical rain
forests.
 More than half of the
world's plant and animal
species.
 Only seven percent of the
earth's surface.
Tropical Rain Forest
Threats
 Formerly covered 20% of
earth’s surface.
 Cleared for logging,
agriculture, and oil
exploration.
 Not only plants and
animals at risk – native
people are at risk.
 Exotic plant (medicinal?)
and animal (pets) trade.
Temperate Forest
There are two types of temperate forests:
1. temperate rain forest
2. temperate deciduous forest
Temperate rain forests
 Have high precipitation, high humidity, and moderate
temperatures.
 Are found in the Pacific Northwest (North America),
Australia, and New Zealand.
The temperate rain forest of the Pacific Northwest has trees
90 m tall including Sitka Spruce, Douglas Fir, and Giant
Redwoods.
Temperate Rain Forest
Temperate
Deciduous
Forest
Temperate Deciduous Forest
Temperate Deciduous Forest
 Found between 30o and 50o N
latitude
 Moderate climate with
change of seasons
 Temperatures range between
30oC and – 30oC
 Averages from 75 to 125 cm of
precipitation
Temperate Deciduous Forest
Vegetation
 Canopy of taller trees such as maples and oaks
 Well-developed understory of small trees and
shrubs
 Forest floor home to ferns, mosses, herbs
 Rich, deep soil
 Most trees lose their leaves in the winter, plants
become dormant
 4-6 month growing season
Taiga
Taiga
Taiga
 Also known as northern
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coniferous forest or boreal
forest
Between 45o and 60o N
latitude (just below Arctic
circle)
Average temperature below
freezing
Winters last 6-10 months
High precipitation
(including snow)
Taiga
 Taiga means "marshy pine forest" in
Russian
 Found in northern hemisphere
 One of the most fragile biomes
 Growing season very short
 Nearly constant daylight in summer
 Many lakes and swamps
Taiga
Vegetation
 Conifers (seeds in cones) that don’t shed leaves
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(needles)
Pointed shape of trees sheds snow
Needles are acidic so soil
is acidic
Few plants on dark forest
floor
Soil forms slowly because
of climate and acidity
Decomposition is slow
Taiga
Animals
 Many lakes and swamps attract birds and
insects in the summer
 Shrews and rodents live year-round –
burrow underground
 Moose and snowshoe hares
Credits
Text:
 http://www.physicalgeography.net/fundamentals/9k.html
 http://www.ucmp.berkeley.edu/glossary/gloss5/biome/index.html
Pictures:
 http://www.worldbiomes.com/
 http://www.ucmp.berkeley.edu/glossary/gloss5/biome/index.html
 http://www.blueplanetbiomes.org/
PowerPoint:
 Arizona Game and Fish Department, 2005