Transcript Ecosystem & the Biosphere

Ecosystem & the Biosphere
Honors Biology
Earth’s Major Biomes
Tundra
Did you know that the Arctic Tundra is the world's
youngest biome? It was formed 10,000 years ago.
Located at latitudes 55° to 70° North, the tundra is a
vast and treeless land which covers about 20% of the
Earth's surface, circumnavigating the North pole.
Tundra
A cold & largely treeless biomes
 Forms a continuous belt across northern
North America, Europe & Asia
 Largest & northernmost biome
 Covers 1/5 of the worlds land surface
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Tundra Climate
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It is cold through all months of the year
Summer is a brief period of milder climates
when the sun shines almost 24 hours a day.
(6-10 weeks)
It has been called "the land of the midnight
sun".
It never gets any warmer than 45 or 50° F.
Winter temperatures don't reach above 20° F
and average -20° to -30°F.
Unusually cold and dry climate
Precipitation totals 6-10 inches of rain/year,
which includes melted snow
Permafrost
Permafrost is a permanently frozen layer of
soil under the surface, characterizes the
tundra
 Even the surface soil above the permafrost
remains frozen for all but 8 weeks of the
year
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Melting permafrost
Plants on the Tundra
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Trees do not usually grow
because the winters are
long & extremely cold
Permafrost prevents their
roots from penetrating far
into the soil
Colorful wildflowers bloom from the end of June to the end of July. There are many
flowering plants like purple saxifrage,mountain havens, wild crocus, arctic poppies,
buttercups, cinquefoil, moss companion, campanulas, arctic azaleas and arctic lupine
Artic Fox
Animals on the Tundra
Caribou
Polar Fox
Polar Bear
Snowy Owl
THE ARCTIC HARE lives farther
north than any other hare
Forest Biomes
Forest biomes are divided into three
main types:
1. Tropical
2. Temperate
3. Boreal (or Taiga)
Tropical Forest
Did you know that the tropical rain forest is a forest of
tall trees in a region of year-round warmth. Rainforests
now cover less than 6% of Earth's land surface.
Scientists estimate that more than half of all the world's
plant and animal species live in tropical rain forests.
Tropical rainforests produce 40% of Earth's oxygen.
Tropical forest
Occurs near the equator known as the
tropics
 Includes parts of Asia, Africa, S. America,
& Cent. America
 Stable temperature and abundant rainfall
make tropical forest the most productive
biome type
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Tropical forest have 2 seasons
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One wet and one dry
Tropical rain forest are characterize by long wet
seasons and tall trees and plants that grow yearround
Tropical dry forest have long dry seasons during
which trees lose their leaves
– Temperate Rain Forest: are found on the Olympic peninsula in
Washington state and in other places throughout the world, such as
South America, New Zealand, and Australia
Plants in the Rain Forest
Competition for light is intense and small
plants live on the branches of tall trees
called epiphytes. (mosses, orchids,
bromeliads)
 Most plants are trees, & some have evolved
to grow as tall as 50 to 60 m
 Treetops for a continuous layer called the
canopy which shades the forest floor
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Epiphytes (EP-uh-FIETS)
Animals of the Rain Forest
animal life is very diverse
 Vertebrates ie: kinds of monkeys, snakes,
lizards & birds
 Insects species are particularly diverse
ie: there is more than 1 million species of
tree-dwelling beetles
 Probably contain about ½ of the worlds
species
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Animals of the Rainforest
tucan
Chimpanzee
King Cobra
Rain Forest: Canopy
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The canopy layer, 25-45
meters high, is a living
roof
The tree tops are exposed
to rain, sunlight, and
strong winds
Animals found: monkeys,
& scarlet macaws
Rain Forest: Understory
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In the understory, the air is
still, humid, and dark.
Vines grow from the soil
to the canopy
The limbs of the trees are
hung with a thick layer of
epiphytes, plants that get
most of their moisture
from the air
Animals/Plants found:
leaf cutter ants, insects,
bats, ferns, & dwarf palm
Rain Forest: Ground
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The ground layer is a
moist forest floor.
Leaves and other organic
materials decay quickly
Roots spread throughout
the top 18 inches of soil
There is great competition
for nutrients
Animals found: rodents,
cats, ants, termites,
worms, bacteria, fungi…
Tropical Rain Forest Climate
The average temperature is about 250C and
receive at least 200 cm of rain annually
 Rain forests belong to the tropical wet
climate group
 One reason for the large number of niches
in rain forests is vertical layering
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Importance of the Rain Forest
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Some rain forest plants are
important sources of medicine
Hardwood trees provide a
source of income for people
Agricultural land is not
common in rain forests
because do not have a large
amount of organic matter
because leaf matter which
disappears so quickly.
Once rain forest soil is
exposed and farmed, it
becomes hard, almost bricklike, and nutrient-poor in a
matter of a few years.
Temperate Forest
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The deciduous forest has four distinct
seasons, spring, summer, autumn, and
winter. In the autumn the leaves change color.
During the winter months the trees lose their
leaves.
Temperate Deciduous Forest
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Occur in N. America, W. & Cent Europe, &
NE Asia
Characterized by distinct seasons and a
moderate climate
Can be characterized by the type of tree that
is most common
1. Coniferous Trees: bear seeds in cones
2. Deciduous Trees: shed their leaves each
year
Temperate Forest Climate
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The average annual temperature in a
deciduous forest is 50° F. The average
rainfall is 30 to 60 inches a year.
Temperate Forest Animals
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Animals hibernate in the winter and living off
the land in the other three seasons.
animals adapt to the land by trying the plants
in the forest to see if they are good to eat for a
good supply of food.
trees provide shelter
Animal use the trees for food and a water
sources.
Most of the animals are camouflaged to look
like the ground.
Temperate Forest Animals
White Tail Deer
American Black Bear
Bald Eagle
Temperate Forest Plants
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The plants have adapted to the forests
by leaning toward the sun. Soaking up
the nutrients in the ground is also a way
of adaptation.
Temperate Forest Plants
Pecan
American Beech
Lady Fern
Taiga or Boreal Forest
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Taiga is the Russian word for forest and
is the largest biome in the world
Taiga/Boreal Forest
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Just south of the tundra lies another biome that
circles the north pole
Also called the boreal or northern coniferous
forest
Somewhat warmer and wetter than tundra, but still
harsh with long severe winters and short mild
summers
The topsoil, which develops slowly from decaying
coniferous needles, is acidic and poor in minerals
Taiga Animals
Snowshoe Rabbit
Wolverine
American Black
Bear
Taiga Plants
Balsam Fir
Douglas Fir
Eastern Red Cedar
Taiga Climate
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The average temperature is below freezing for
six months out of the year.
The winter temperature range is -54 to -1° C
(-65 to 30° F).
The winters, as you can see, are really cold,
with lots of snow
The summer gets as low as -7° C (20° F). The
high in summer can be 21° C (70° F).
Grasslands
•Grasslands are dominated by a variety of grasses
•Grasslands are known by different names in different
parts of the world
•Prairies: North America
•Steppes: Asia
•Pampas: South America
•Veldts: South Africa
1. Temperate Grassland
Temperate grasslands
Usually formed in the interior of continents
at about the same latitude as temperate
deciduous forest
 Rainfall patterns make these areas too dry to
support trees
 Have rich fertile soil
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Temperate grasslands
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Once covered a large
portion of the US and
supported huge herds
of herbivores like
bison
Temperate Grassland Animals &
Plants
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The American Bison
2. Savanna
Savanna
Savanna is a grassland community with
scattered individual trees. This Biome
covers areas of central South America,
central and southern Africa and parts of
Australia.
 The climate generally shows 3 distinct
seasons: cool and dry, hot and dry,
warm and wet, in that order.
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Soils are generally
porous with a thin
humus layer; and
water drainage is
rapid.
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Large herbivores
(zebras, giraffes)
and burrowing
animals are
commonly most
active in the rainy
season and many
are nocturnal.
3. Chaparral
Chaparral
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Chaparral (scrubland) are regions of dense,
spiny shrubs with tough evergreen leaves
found along coasts where cool ocean
currents circulate offshore to make mild, rainy
winters and long, hot dry summers
Occur in Mediterranean and coastlines of
California, Chile, SW Africa, and S. W.
Australia.
This type of habitat is maintained by periodic
fires
Chaparral Plants & Animals
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Many shrubs have root
systems and seeds that
are adapted for fire; root
crowns may be fire
resistant and resprout
quickly, others have
seeds that only
germinate after a fire.
Other plants are
colonial and use
asexual reproduction.
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Browsers such as
deer, fruit-eating
birds, rodents,
snakes and lizards
are common
Desert
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Are areas that receive an average of less
than 25 cm of rainfall/year
Desert Climate
Areas: large parts of N. Africa, Cent.
Australia, SW N.A., E. Asia
 Temperatures may fall to as much as 54 F at
night b/c the dry air is poor insulators (heat
builds during the day, but escapes at night)
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Cold Deserts
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Contrary to popular belief, not all deserts are hot.
The Great Basin (W. U.S.) and the Gobi ( E. Asia)
are hot in the summer and cold in the winter
Gobi Desert
Vegetation
Leaves have a waxy covering that reduces
evaporation
 Plants have only few stomata and may only
open at night
 Cactus is common type
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Desert Plants
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Has expandable body
that can store water &
leaves that have
evolved into sharp
spines that protect
from herbivores
1 Saguaro can hold
1,000 kg of water
Found in Arizona,
California, & Mexico
Saguaro Cactus
Desert Animals
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Must conserve water
Spend much of the day
avoiding the heat by
burrowing into the
ground
Kit foxes, some
lizards, snakes are
only active at night
Banded Gila Monster
Thorny Devil
Ocean Zones
Cover 70% the Earth’s surface w/ average
depth of 3.7 km (2.3 mi)
 Deepest part are about 11 km (6.8 mi)
 Water contains about 3% salt
 Light availability is an important factor
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Light availability
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Aphotic Zone: sunlight cannot penetrate &
photosynthesis cannot occur
Photic Zone: the part of the ocean that receives
sunlight. The depth varies
Oceanic Zone
Neritic
Intertidal Zone
Photic Zone
Pelagic Zone
Benthic Zone
Aphotic Zone
Thermal Vent
Continental Shelf
3 Zones relative to the oceans
edges
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Intertidal zone: the area of shoreline that is
twice daily covered by water during high
tide & exposed to air during g low tide
Organisms adapted to periodic exposure
due to tides
Organisms must be able to withstand the
force of crashing waves
Animals of the Intertidal Zone
3 Zones relative to the oceans
edges
2. Neritic Zone: extends from the intertidal
zone over the continental shelf and to
relatively shallow water depths of 180 m.
 Most productive zone in the ocean
supporting more species than any other
zone
 Water is shallow enough for photosynthesis
to occur
Upwelling (currents) carry nutrients from
the ocean bottom & mix them with nutrients
from runoff
 These waters are rich in plankton which are
consumed by larger animals
 Numerous fish, sea turtles & other animals
are found here
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Coral reefs form in tropical areas (very
productive & rich in species
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Are built by coral animals
over a long time period
External skeleton of
calcium carbonate. As the
animals grow & die, the
skeletons accumulate to
form the base of the reef
Reef is home to many
specie of fish, mollusk, &
other animals
3 Zones relative to the oceans
edges
3. Oceanic Zone: the deep water of the ocean
sea
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Photic areas, nutrients levels are too low to
support as much life
½ photosynthesis on Earth takes place in the
oceanic zone
Division of Neritic & Oceanic
Zones
The open ocean is known as the pelagic
zone
 The ocean bottom is known as the benthic
zone
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Estuaries
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Occur where freshwater & saltwater meet and
serves as a nursery ground for species
Are more productive b/c they have shallow,
nutrient-laden waters
Freshwater Zone
Temperature variations within a lake are an
abiotic factor that limits the kinds of
organisms that can survive in deep lakes
such as light
Wetlands: places where
Land and water meet
Marsh: no trees, but water flows
Bogs: get their water
From rain & does not flow
Swamp: have trees
Lakes & Ponds divided into 2
categories:
1.
Eutrophic Lakes are rich on organic matter &
vegetation so waters are murky
 As the number of plants & algae in a lake grows, the
number of bacteria feeding on decaying organisms also
grows
 These bacteria use the oxygen dissolved in the lake’s
water killing the organisms that need oxygen to survive
 Lakes naturally become Eutrophic over a long period of
time
Eutrophic Lakes
Lakes & Ponds divided into 2
categories
2. Oligotrophic Lakes: contain little organic matter
the water is much clear & the bottom is usually
sandy or rocky
Rivers & Streams
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A river or stream is a body of freshwater
that flows down a gradient or slope towards
its mouth
Rivers & Streams of Escambia
Co.
http://wildflowers.jdcc.edu/Rivers%2
0and%20Streams.html