Transcript Biomes - Maria Regina High School

Chapter 6-1, 6-2
What is a Biome?
6-1
 Biomes are large regions of Earth
that are characterized by specific
climate, plants and animals
 Biomes are mostly described by
their vegetation
 The plants that can grow in the
biome are dictated by the weather
 In turn, the available plants for
food and shelter, dictate the type
of animals that may live there
 Ex: Mahogany trees grow in
tropical Climates because they
cannot survive cold, dry weather
Biomes and Climate
 Climate – long term weather
conditions of a particular region
 Ex: precipitation, humidity, winds,
temperature
 Temperature – Most organisms
(plants and animals) are adapted to
living in a particular range of
temperatures
 Physical features of these organisms
prevent them from being
comfortable in temperatures
outside their range
 Precipitation – The larger an
organism is, the more water it needs
 Deserts usually support small
shrubs and grasses
 Plants and animals that survive in
limited water, have adaptations that
enable them to survive
 Ex: Camel humps, cactus thorns
Latitude and Altitude
 Latitude – the distance north
or south of the equator
 Directly relates to the overall
temperature of the area
 Most food grown globally
between 30° and 60° north of
the equator and 30° and 60°
south of the equator
 Altitude – the height of an
object above sea level
 The higher the altitude, the
colder the air and the less
oxygen available
Forest Biomes: Tropical Rain Forest
 Located in a belt around the
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Earth near the Equator
Play vital roles in regulating
Nitrogen, Oxygen and Carbon
cycles
Warm, humid, ~200 – 450 cm
rainfall per year(80 to 180
inches)
Sunlight and temperature
fairly constant year-round
Contains more biodiversity
than any other biome
6-2
Tropical Rain Forest cont.
 The soil is very nutrient poor
 As organisms decompose
(very rapidly in the humid and
hot conditions) the nutrients
are reabsorbed into the plant
roots quickly
 Slash and burn practices still
in effect in small areas of rain
forest
 Trees often grown roots from
their branches down to the
soil to help brace the large tree
body in thin soil
Rain Forest Stratification
 Rainforests are layered (stratified)
 Emergent Layer – Top of the tallest
trees 60 – 70 m
 These trees gather direct sunlight
 Canopy – Trees are about 30 m tall
 Split into upper canopy (trees
receive 95% of the sunlight) and
lower canopy
 Some plants and flowers grow on
the trees
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Ex: Epiphytes like the orchid
 Most animals live in the canopy
because most fruits and flowers live
in the canopy
 Understory – trees and plants
about 3.5 m tall
 Adapted to living in less sunlight,
have broad dense leaves
 Most house plants are understory
plants
Rainforest Biodiversity
 Because the diversity of plants is
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so high, the animal communities
are equally divers
Plants and animals have
developed amazing adaptations
to help them survive
Anteaters have incredibly long
tongues for eating ants and
termites
Sloths move so slowly that
fungus and moss grow on their
bodies
The wreathed Hornbill bird uses
it’s beak to crack open nutshells
Stuff we use…
Coffee Tree
Habitat Destruction – 100 acres of tropical
rainforest are destroyed every day by logging
operations, agriculture or oil exploration. This
habitat destruction is the primary reason for
species extinction. Exotic-pet trades and plant
trade are also threats. These practices are illegal
and may lead to species extinction.
Cocoa Tree
Temperate Rain Forest
 Found in North America, Australia
and New Zealand
 Think Twilight Series – Pacific
Northwest
 High humidity and moderate
temperatures year round…rarely
freezes due to ocean waters
keeping mild air temperatures and
wind which produce copious
amounts of rain when they meet
the coastal mountains
 Trees are draped with mosses and
lichens. The forest floor is covered
in ferns
Temperate Deciduous Forest
 Trees drop their broad, flat
leaves every fall
 Generally found between
30° and 50° north latitudes
 Dramatic seasons with
dramatic shifts in
temperature (Freezing in
the winter to ~90°F in the
summer)
 Organic matter
decomposes very slowly so
the soil is very fertile and
holds on to nutrients well
Deciduous Forest Plants
 A deciduous forest is stratified like
a rain forest
 Tall trees occupy the canopy
 EX: maples, oaks, hickory
 Small trees and shrubs dominate
the understory
 More light gets through to the
understory in a deciduous forest,
so a larger variety of plants exists
on the forest floor
 EX: Mosses, ferns, herbs
 Plants are adapted to surviving
cold weather
 Trees drop leaves, plant bulbs go
dormant
Deciduous Forest Animals
 The animals have developed ways of
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using the plants as sources of food
and shelter
Squirrels live in trees, eat nuts, seeds
and fruit
Grasshoppers eat almost all types of
vegetation
Deer nibble on leaves from trees and
shrubs
Birds migrate to warmer weather in
the winter and return in the spring
for nesting and food
Some animals hibernate to survive
the winter
Taiga (Coniferous Forest)
 Stretches in a band across the
northern hemisphere
 Winters are 6 to 10 months
long
 Average temperature is below
freezing (and often -20°C)
 Plants grow the most during
the summer due to the almost
constant daylight and lots of
precipitation
 Midnight sun
Plants of the Taiga
 Coniferous trees are predominant
 Needle-like leaves with waxy coating
and natural antifreeze allow these
needles to perform photosynthesis
year round without losing too much
water
 These are cone-bearing trees
(containing the seeds)
 The tree itself is shaped like a cone to
prevent snow build-up
 The needles of conifers are acidic,
this causes the soil to become acidic
when they fall
 Forest floors are mostly bare because
plants cannot grow in the acidic soil
 Slow decomposition means slow soil
turnover
Animals of the Taiga
 Summer attracts birds to
the taiga swamps, most of
whom migrate south
during the cold winters
 Some animals hibernate to
survive the harsh, foodscarce winters
 Ex: Jumping mice
 Some animals shed their
brown summer fur for
camouflage white winter
fur to avoid predation by
lynxes or tigers
 Ex: Snowshoe hare
Limited Water Biomes
6-3
 These biomes are characterizes by smaller plants due
to less rainfall than their forest counterparts
 Warm areas with little precipitation
 Savanna
 Desert
 Temperate areas with little precipitation
 Temperate Grassland
 Chaparral
 Desert
 Cold areas with little precipitation
 Tundra
 Desert
Savanna
 Tropical grassland biome
 Found in Africa, western
India, north Australia and
parts of So. America
 Rain falls during the wet
season which only lasts a
couple months a year
 This is the only time of year
that plants grow
Plants of the Savanna
 Plants must be able to survive
long periods without water in
high temperatures.
 Most lose their leaves or die
down to the ground and resume
growth when rain returns
 Large, superficial roots systems
spread wide under topsoil to
absorb water
 Grasses have vertical blades
 Reduces exposure to sun and
water loss
 Many plants have thorns as
deterrents for herbivores
looking for water-rich foods
Animals of the Savanna
 Many grazing animals are
migratory and follow the rains
 Elephants, zebras
 Some predators follow and
stalk migratory animals
 Lions
 Many herbivores have been
adapted for eating at various
heights
 Giraffes in trees, gazelles on
grasses, rhinos on shrubs
 Most offspring are born during
the rainy season when there is
an abundance of food and high
chance of survival
Lion, Gazelle, Cheetah, Ostrich,
Giraffe, Elephant, Hyena
Temperate Grasslands
 Found on interior of continents
 Moderate rainfall but not
enough for trees to grow
 Prairies of No. America, pampas
in So. America, steppes in Asia
and the veldt in So. Africa
 Mountains usually play a key
role
 As clouds move over, they
precipitate, leaving little
moisture in the air for the flat
lands (~10 inches a year)
 Precipitation increases as the
clouds move farther and
farther away from the
mountains (~35 inches a year)
Plants of the Grasslands
 Grasses and wildflowers
 Shrubs and trees only grow in
areas of excess water (usually
near streams)
 The root systems are deep, dense
and extensive for surviving
drought and fire
 Plants die back to their roots in
the winter
 Low temperatures mean slow
decay…much slower than the
rate of regrowth each spring
 Grasslands have the most
fertile soils in the world
 America’s farmland for seed
crops
Animals of the Grasslands
 Grazing animals have
broad, long flat teeth for
grinding grasses
 Bison, antelope
 Some animals burrow to
hide from predators, fire
and weather
 Badgers, prairie dogs,
burrowing owls
Threats to the Grasslands
 Over-farming and grazing on the grasslands have
changed the ecosystems
 Crop plants don’t have the same dense root system
 Causes the soil to erode
 Regular plowing also increases soil turnover
 Nutrients are used up faster in the soil than they are
replaced
 Lack of nutrients means the native grasses cannot
regenerate, turning the fertile grasslands into a more
desert-like biome
Chaparral
 Also known as the
Mediterranean biome
 Moderately dry, coastal climate
with little to no rain in the
summer
 Supports more life than a
desert but less than the
grasslands
 Found in patches at about 30°
north and south of the equator
 Think Greece, the Hollywood
sign in CA, shrubs lands of the
old west
Plants of the Chaparral
 Lots of low-lying evergreen
shrubs and small trees in
dense patches
 Common plants
 Shrub oak, olive trees, herbs
 Small leathery leaves retain
water and have special oils
that promote burning in a fire
 This helps kill off competing
species and only tiny bits of
surviving tissue are needed
for the plants to resprout
Animals of the Chaparral
 Camouflage is a valuable tool
for chaparral animals
 Quails, lizards, snakes, deer,
chipmunks all have
brownish-gray coloring
which enables them to
remain hidden from
predators
Deserts
 The driest places on Earth,
but not necessarily the
hottest
 Temps range from 104° in the
hot sun to near freezing at
night due to lack of
insulating moisture in the
air
 Located near mountains that
block the passage of clouds
and prevent rainfall
Plants of the Desert
 These plants all have special adaptations to
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prevent water loss
Succulents are plants with thick waxy leaves
designed to retain moisture during long
droughts
Some plants, like cacti, are covered in thorns
to deter animals from eating them for their
juicy flesh
Root systems are extremely superficial and
spread out far to obtain rainfall (which does
not penetrate into the soil far)
Some plants die during dry periods and drop
seeds which germinate, grow and bloom very
quickly during the next rain fall
Some plants may even live with 30% water
mass (Most plants die if their water mass is
below 50 to 75%)
Animals of the Desert
•Reptiles have thick scaly skin which prevents
water loss
•Ex: Snakes, Gila monsters
•Amphibians bury themselves into the ground and
hibernate through a process called estivating to
avoid drying out in the desert dry season
•Some animals have become well adapted at
finding shelter in desert plants
•Ex: Elf owl burrows into a cactus to build a
home
•Desert insects are covered in thick exoskeletons
(body armor) to prevent excessive water loss and
as protection
•Many animals are nocturnal and come out during
the cooler temperatures of the night or at dusk
Tundra
 Found in the northern arctic
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regions
Way too cold and dry for trees
to grow
The deeper layers of the soil
are called permafrost and
remain frozen year-round
When the top layer thaws in
the summer, the surface of the
tundra can become boggy and
spongy
The bogs become breeding
grounds for insects and the
birds that feed on them
Plants of the Tundra
 Mosses and lichens are able to grow
on bare rock without soil (remember
Primary Succession?)
 The soil is very thin if present at all
and plants have shallow, wide roots to
help them anchor against the winds
 Flowering plants are very short
enabling them to avoid the intense
winds and absorb heat from sunlight
that is reflected off the rocks and soil
 A few woody trees have evolved dwarf
forms that may grow flat or along the
ground
 Willow and Birch
Animals of the Tundra
 Birds will migrate and mate
during the short summer
 Insects, mollusks, plants and
worms are prevalent as food
 Animals usually migrate in search
of food or water
 Caribou, moose
 Some animals burrow to avoid
the harsh winters but are still
active
 Lemmings, mice, hares
 Other animals have different fur
colors for the winter and summer
seasons and are very well
insulated
 Arctic Foxes
Threats to the Tundra
 Because the food chains are short and simple, the balance
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of life in the biome may be disrupted very easily
Damage to this biome requires a long period of time for
recovery because of the incredibly slow turnover of life, soil
and plants (due to the year round freezing temperatures)
Humans almost never penetrated into this biome until
recently
Discovery of oil has lead to exploration, extraction and
transport of oil which has had huge impacts on the tundra
biome
Habitat destruction has occurred, not only from the
process of oil mining, but also from oil spills, leaks and
pollution from other toxic materials