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CHAPTER 15
BIOSPHERE
Part of Earth where life exists
BIOTA- all the living things on
Earth
Biosphere is made up of
 HYDROSPHERE- all the water on the
Earth- solid, liquid and gas
 ATMOSPHERE- air blanketing the Earth
 GEOSPHERE- rocks and nutrients of the
Earth as well as its contours
What is a BIOME?
 Defined as- a large region characterized by
a specific climate and certain types of
animals and plants
 CLIMATE- average weather over an
extended period of time
 2 most important factors- PRECIPITATION
AND TEMPERATURE
CLIMATE
 Defined as weather conditions
(temperature, precipitation, humidity, and
winds ) in an area over a long period of time
 Is determined by AVERAGE
TEMPERATURE AND PRECIPITATION
(see pyramid on page 144)
Climate is also affected by latitude
and altitude
 LATITUDE- distances north or south from
the equator
 ALTITUDE- distance above or below sea
level
 Climate gets colder as altitude and latitude
increase
TYPES OF CLIMATES
 1. TROPICAL- near the equator between
the Tropic of Cancer and the Tropic of
Capricorn- warm and humid year round
 2. TEMPERATE- experiences warm and
cold seasons.
 3. POLAR– far north and far south typically
cold and often below freezing
6 types of biomes
1. TUNDRA
2. DESERT
3. TEMPERATE
4. TAIGA
5. TROPICAL
6. GRASSLAND
Vegetation determines the name of
a biome.
 The plants that grow there determine what other
organisms can live there
 Plants in specific biomes have characteristics or
adaptations that allow the plant to survive
 Adaptations can be size, shape, and colors
(Example- trees in the tundra are small- why?
Cactus do not have leaves- Why?
TUNDRA
 COLD TEMPERATURES and very little
precipitation
 No TREES- mainly mosses and lichens
 Located North of the Arctic circle
 Short summers so only a few cm. of topsoil thaws
 Covers the area in bogs and swamps
 PERMAFROST- the layer underneath the topsoil
that stays frozen year round
ANIMALS OF THE TUNDRA
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

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Migratory birds fly to breed here in the summer
Many insects live in the bogs and swamps
Caribou MIGRATE through the tundra
Snow owls, Arctic foxes, Snowshoe hares
 Very fragile ecosystem that can be easily
disrupted by humans- oil exploration is its biggest
threat
DESERT
 Receive less than 25 cm of rain per year
 Little or no vegetation
 Typically located near large mountain ranges that
block any moisture- “Rain Shadow Effect”
 Plants called SUCCULENTS- (cactus) have thick
fleshy stems to store water
 Reptiles- have thick scaly skin to prevent water
loss
 Most desert animals are NOCTURNAL- active at
night
FOREST
 CANOPY- the large leaf coverage by the
tall trees
 UNDERSTORY- the shaded area below the
canopy for shrubs and brush
FOREST BIOMES
 TROPICAL RAIN FOREST–
–
–
–
–
–
Located around a belt near the equator
help regulate world climate
Major factor in nitrogen, oxygen and carbon cycle
Get equal sunlight nearly year round- humid and warm
200-450cm of rain/ yr
Extremely diverse species of plants and animals 300
species per hectare possible
– Large canopy- means smaller plants must have several
adaptations
– Animals include- parrots, monkeys, snakes, sloths,
many species…
TEMPERATE RAIN FORESTS
 Found in Pacific Northwest, Australia, New
Zealand.
Typically found near the oceans where
prevailing winds bring in moisture and warm
air.
-Trees draped with mosses and lichens. Lush
ferns on the forest floor.
-Large evergreen trees dominate this biome.
TEMPERATE DECIDUOUS
FORESTS
 Typical of North American forests DECIDUOUS TREES- trees that drop their leaves
during the winter months due to lack of water
(frozen)
 Receive 75-125 cm of precipitation/year
 Plants have growing season then dormant
season- (evidence is rings on trees)
 More plants such as ferns and herbs can grow due
to lack of canopy
 Trees- birch, beech, oak, maple, elm , cottonwood
 Animals either migrate or store food for winter
TAIGA
 NORTHERN CONIFEROUS FOREST(Cone-bearing forest)
 Located just below Arctic Circle- Northern
Canada, Alaska, Russia
 Average temperatures below freezing- long
winters and short summers
 Thin coniferous trees
 Moose, bears, wolves
GRASSLANDS, DESERTS, AND
TUNDRA
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Less rainfall than forest biomes
Diversity of species also decreases
Number of each species may be very large
More pioneer species and less mature
species
TEMPERATE GRASSLANDS
Prairies in the midwest (US), steppes in Russia and pampas
in South America
Grasses with very few trees
Hot summers and cold winters
Average rainfall 50-88 cm/year
Natural temperate grasses have been replaced by crops or
grazing areas
Grazing animals- bison, pronghorn antelope
Burrowing animals- badgers, prairie dogs and owls
Farming and Overgrazing is a big threat to the grasslands
because of wind and water erosion
SAVANNAS
 Tropical and subtropical grasslands near the
equator
 Full of grasses, scattered trees and shrubs
 MIGRATION of Large herds of grazing animals
and the predators that hunt them
 Have a wet season and a dry season
 Many animals bury themselves in the ground
during the dry season and are active only during
the wet season- ESTIVATION
CHAPPARAL
 Also called TEMPERATE WOODLANDS
 Around the “HOLLYWOOD” sign, and other
coastal areas that have a Mediterranean
climate.
 PLANTS- more broad leafed shrubs than
evergreen trees. Leaves are very leathery
and excellent at retaining water.
CHAPPARAL
Plants also contain special oils that promote
burning and can re-sprout with little bits of
stem remaining.
ANIMALS- Quail, lizards, chipmunks, and
mule deer.
CAMOUFLAGE- shape or coloring that allows
the animal to blend into the environment.
Biomes:
Temperature and moisture dependence
(Ricklefs 2001
AQUATIC ECOSYSTEMS
 FRESHWATER ECOSYSTEMS- lakes,
ponds (non moving water), rivers, streams
(moving water)
 MARINE ECOSYSTEMS- ocean, coastal
marshes, coral reefs
AQUATIC ECOSYSTEMS
 Factors of aquatic ecosystems
1.
2.
3.
4.
5.
temperature
sunlight
oxygen
nutrients
salinity- (concentration of salt)
AQUATIC ECOSYSTEMS
 3 CATEGORIES OF ORGANISMS
1. PLANKTON- organisms that float near
the surface (phytoplankton and zooplankton)
2. NEKTON- organisms that are free to
swim throughout the ecosystem (fish,
turtles)
3. BENTHOS- organisms that dwell on the
bottom- (mussels, sponges, barnacle )
WATERSHED
 is an area of land that drains all the rainfall to a
common outlet such as a stream or river that
eventually leads to a lake or ocean.
FRESHWATER ECOSYSTEMS
 Rivers and streams RUNOFF- nutrients and sediment washed
from the surrounding land into the riverbeds
 RIVERS- shallow fast flowing rivers contain
a HIGH OXYGEN CONTENT– Deep slow moving rivers have little oxygen
dissolved in it
FRESHWATER ECOSYSTEM
 LAKES AND PONDS
1. LITTORAL ZONE- shallow area near the
shore where many plants can grow-
2. BENTHIC ZONE- deep area of a lake where
no sunlight can reach- no plant life- mostly
decomposers
3. LIMNETIC ZONE- open water located away
from the shore. Plankton is the only producer
THERMOCLINE
Thin line of water where
the temperature drops
drastically.
LAKE TURNOVER
 Water is most dense at 4 degrees Celsius and will
move to the bottom of the lake.
 This turnover brings rich nutrients to the surface.
EUTROPHICATION
 a process where water bodies receive
excess nutrients that stimulate excessive
plant growth. Can lead to fish kills.
IMPORTANCE OF THE
WETLANDS
1. BUFFER SHORELINES AGAINST EROSION
2. REDUCE THE DAMAGE DONE BY FLOODING
3. PROVIDE SPAWNING GROUNDS FOR MANY
FISH AND SHELLFISH
4. PROVIDE HABITAT FOR MANY MIGRATING
BIRDS
5. TRAP AND FILTER RUNOFF WATER TO KEEP
IT FROM POLLUTING LAKES AND OCEANS
COASTAL WETLANDS
ESTUARY- an area in which fresh water from
a river mixes with salt water from the ocean
- currents form dropping the mineral rich
nutrients to the bottom
SALT MARSHES- shoreline of the Gulf of
Mexico and Atlantic Coast
COASTAL WETLANDS
 MANGROVE SWAMPS-coast along the tropics and
subtropic zones. Dominated by mangrove trees- Mangrove
trees have special adaptations of their roots to get fresh
oxygen and produce an oil on their leaves to rid them of
excess salt
 BARRIER ISLANDS- rocky shore that typically runs
parallel to the shore- help protect the wetlands
 THREATS TO ESTUARIES- development for building
sites, pollution, agricultural runoff (fertilizers and pesticides)
COASTAL WETLANDS
 CORAL REEFS- limestone ridges built by
tiny coral animals called coral polyps for use
as an exoskeleton. Corals are predators that
sting their prey with tentacles. Corals live
only in clear and warm water where there is
enough light for photosynthesis
 Threats to coral reef- oil spills, sewage, and
overfishing
OCEAN ZONES
 INTERTIDAL ZONE- sometimes underwater
sometimes not- depends on tide
 NERITIC ZONE- few cm to 200m deep
 BATHYAL ZONE- 200m to 2000m
 ABYSSAL ZONE- more than 2000m
OPEN OCEANS
 SUNLIGHT CAN ONLY PENETRATE 330
FEET OF OCEAN WATER- SO MOST
PLANTS ARE NEAR THE SHORE
 OPEN OCEAN HAS ONLY
PHYTOPLANKTON TO BE A PRODUCER
SO THEREFORE IS ONE OF THE LEAST
PRODUCTIVE OF ALL ECOSYSTEMS
OPEN OCEANS
 ZOOPLANKTON like jellyfish and tiny
shrimp feed on the phytoplankton. Larger
fish and whales feed on zooplankton.
 Threats to oceans- pollution, overfishing,
large fishing nets catching mammals such
as dolphins and sea lions
Earth’s human population continues to grow.
 Earth’s human carrying capacity is unknown
and is ever changing.
WORLD POPULATION
 Technology has helped to increase Earth’s
carrying capacity.
– gas-powered farm equipment
– medical advancements
The growing human population exerts
pressure on Earth’s natural resources.
 Nonrenewable resources are used faster
than they form.
– coal
– Oil
– Natural gases
 Renewable resources cannot be used up or
can replenish themselves over time.
–
–
–
-
wind
water
Sunlight
plants
• Resources must
be properly
managed.
 An ecological footprint is the amount of land
needed to support a person.
• The land must produce and maintain enough
– food and water
– shelter
– energy
– Waste
– In the USA each person produces 4.2 lbs of waste per
day 4.2 x 365 = 1533 lbs per year.
 Several factors affect the size of the
ecological footprint.
– amount and efficiency of resource use
– amount and toxicity of waste produced
Pollutants accumulate in the air.
 Pollution is any
undesirable factor added
to the air, water, or soil.
 Smog is one type of air
pollution.
– sunlight interacts with
pollutants in the air
– pollutants produced by
fossil fuel emissions
 Smog can be harmful to human health.
• Acid rain is caused by fossil fuel emissions.
– produced when pollutants in the water cycle cause rain
pH to drop
– can lower the pH of a lake or stream
– can harm trees
Air pollution is changing Earth’s
biosphere.
 The levels of atmospheric carbon dioxide
rise and fall over time.
 High levels of carbon dioxide are typical of
Earth’s warmer periods.
 The greenhouse effect slows the release of
energy from Earth’s atmosphere.
–
–
–
–
sunlight penetrates Earth’s atmosphere
energy is absorbed and reradiated as heat
greenhouse gases absorb longer wavelengths
carbon dioxide
(CO )
Greenhouse
gas molecules
methane (CH )
water (H O)
rerelease
infrared
radiation
2
4
2
 Global warming refers to the trend of
increasing global temperatures.
North Pole
Water pollution affects ecosystems.
 Pollution can put entire freshwater
ecosystems at risk.
 Indicator species provide a sign of an
ecosystem’s health.
– amphibians
– top predators
Biomagnification causes accumulation of
toxins in the food chain.
 Pollutants can move up
the food chain.
– predators eat
contaminated prey
– pollution accumulates at
each stage of the food
chain
• Top consumers, including
humans, are most affected.
Preserving biodiversity is important
to the future of the biosphere.
 The loss of biodiversity has long-term
effects.
– loss of medical and technological advances
– extinction of species
– loss of ecosystem stability
Loss of habitat eliminates species.
 Habitat fragmentation prevents an organism
from accessing its entire home range.
– occurs when a barrier forms within the habitat
– often caused by human development
 Habitat corridors are a solution to the
problem.
– corridors can be road overpasses or underpasses
– allow species to move between different areas of
habitat
Introduced species can disrupt stable
relationships in an ecosystem.
 An introduced species is one that is brought
to an ecosystem by humans.
– accidental
– purposeful
 Invasive species
can have an
environmental
and economic
impact.
 Invasive species often push out native
species.
– Burmese python (Florida Everglades)
 Invasive species often push out native
species.
– mice (Australia)
THREATS to Aquatic
Ecosystems
 1. POLLUTION- blocks sunlight to plants as
well as killing organisms
 2. SALINITY- from evaporation- leads to
inhabitable conditions
 3. URBANIZATION- turning wetlands and
estuaries into Sea Ports
 4. INVASIVE SPECIES- new species take
over cause they have no competition- exzebra mussels
THREATS to Aquatic
Ecosystems
 5. OVERFISHING 6. OVERGROWTH of PLANTS
EUTROPHICATION- sudden increase in
nutrients that can lead to “ Bloom” of plant
life that can take all the oxygen away from
the fish
KEY CONCEPT
Conservation methods can help protect and
restore ecosystems.
Sustainable development manages resources
for present and future generations.
 Sustainable development meets needs
without hurting future generations.
– resources meet current needs
– resources will still be available for future use
 The timber industry has started to adopt
sustainable practices.
• Global fisheries have adopted several sustainable
practices.
– rotation of catches
– fishing gear review
– harvest reduction
– fishing bans
Conservation practices focus on a few
species but benefit entire ecosystems.
 The Endangered Species Act
works to protect individual
species from extinction.
 A listed species is often called
an umbrella species.
– the habitat in which the
species lives must be
protected
– other species are protected
because they share the
ecosystem
Protecting Earth’s resources helps
protect our future.
 The Environmental Protection Agency (EPA) was created in 1970.
 The EPA develops policies and regulations to protect the environment.
 Legislation helps to protect the environment and endangered species.
– Clean Air Act
– Clean Water Act
– Endangered Species Act
 The National Park
Service helps
manage public
lands.
• The park system includes
over 390 areas, covering
84 million acres.