Transcript chapter three - Nutley Public Schools

Change in the Biosphere
Chapter 3 (pgs 34-49)
The Changing Environment
 Humans have only lived on earth for
<0.5 million years
 How old is earth?
 How did earth form?
 Earth has been changing since it
formed
 Do you know some ways that earth is
changing?
 Most natural changes are so slow that
you don’t see them in a lifetime
 Some rapid changes have taken place
from human activities
Changes in the Lithosphere
 ***Remember – the
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lithosphere is the layer of land
on earth***
The lithosphere is made of several
large moveable tectonic plates
Molten (liquid) rock from inside
earth oozes out through the
cracks between the plates
The molten rock hardens (as it
cools) pushing apart the plates –
this may cause earthquakes
Mountain chains form when the
plates cause the Earth’s surface to
buckle
Earthquakes:
 Vibrations caused by the Earth’s crust “slipping” along
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a fault line (break in the Earth’s crust)
Richter Scale – scale used to measure
earthquake intensity
Ranges from 1 – 10
(9.5 is most powerful to ever be recorded)
Most earthquakes take place on or near fault
lines
The biggest faults are near the boundaries where
tectonic plates meet
This is why California has more earthquakes than NJ
Volcanoes:
 A mountain built from
magma (melted rock) that
rises from the Earth’s
interior to its surface.
 Often located near tectonic
plate boundaries.
 On land or under sea.
 “Ring of Fire” contains
75% of world’s active
volcanoes that are on land.
Other Lithospheric Changes
 Weathering – the
breaking down of rock by
heat, water, ice, wind, and
pressure – no movement
 Erosion – the broken
down rock is then carried
off by water, wind, ice, and
gravity - movement
Changes in the Hydrosphere
 ***Remember – the
hydrosphere includes all parts
of earth made up of water***
 As the continents have changed,
so have the bodies of water
 Most water changes occur slowly
and steadily over time
 Other water changes occur in a
series of cycles:
 Ice ages – millions of years
 El Nino – every 4-7 years
Ice Ages
• Long periods of cooling, when
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glaciers move from poles and cover
much of Earth
Glaciers - huge masses of ice
form called
After the ice age, the glaciers
retreat back to the poles
Evidence of five ice ages in the
Earth’s history (most recent ended
12,000 to 10,000 years ago
When glaciers move, they scrape
across earth moving rocks and
water to new places
El Nino
• Every December, a warm,
nutrient-poor water current
flows southward along the
coast of South America
• Normally this warm current is
quickly replaced by a cold,
nutrient rich current during
an upwelling
• Every 4-7 years, the
upwelling doesn’t occur
• The nutrient poor water
cannot support fish life
Changes in the Atmosphere
 Early Earth’s atmosphere was
mostly water vapor, carbon dioxide
& sulfur from volcanic eruptions.
 Bacteria evolved that could perform
photosynthesis and released first
oxygen into atmosphere.
 For the past 3.5 billion years, the
atmosphere consists of recycled
nitrogen, oxygen, carbon dioxide &
water vapor
Changes in the Atmosphere
 Much of earth’s carbon is cycled
through the carbon cycle
 Some is stored in the bodies of
organisms – dead or alive
 Fossil fuels (coal, natural gas) –
formed by breakdown of dead
organisms
 When we burn fossil fuels, we
release carbon dioxide
 Greenhouse Effect-release of stored carbon
into atmosphere by burning organic matter,
which influences the temperature of the Earth.
Check for Understanding:
 1.Through what process does weather affect the shape of land?
 2. In what ways does El Nino affect the economy?
Needs of Organisms
 An environment should provide
an organism with everything it
needs to live
 Every organism has a different
set of needs and has evolved to
fit its environment
 All organisms have certain needs
in common:
 Water
 Source of energy
 Living space
 Suitable climate
Water
 Fresh water is one of the most
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important abiotic factors in
support of life
Plants need water to grow
Animal populations need plants
and water
Ocean organisms are affected by
water quality
Warm water contains less
dissolved oxygen than cold water
– can’t keep organisms alive
Food and Energy
 All energy used by organisms
comes from the sun and is
stored as food
 Plants capture energy from
sun and make food through
photosynthesis
 Animals eat plants and get
energy
 Food contains energy,
minerals, and vitamins
 Nutrients-all the substances
that an organism requires from
food.
Living Space
 All organisms need space to live
and obtain materials
 Plants need space between them
to get sunlight and water
 Animals need space to get food,
water, mates
 Territory – area claimed as a
living space by an individual
animal (mark their territory)
 Size of territory – determined by
animal
 They will compete till DEATH!
Climate
• Climate – the temperature and
weather that an organism is
adapted to live in – it produces
varied responses in organisms
 Range of tolerance – acceptable
range of temperature for an
organism’s survival
 Most organisms’ body
temperatures are determined by
the environment (cold blooded)
 Many organisms become
dormant to survive cold
temperatures
Climate
 Dormant – all metabolic life
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processes slow down in an
organism [ex: plants in winter
bacteria in refrigerator]
Other organisms (warm
blooded) use energy to maintain
a high body temperature
Warm blooded animals need 10 X
as much food!
Some animals also become
dormant (hamsters, worms)
Hibernation – heart rate and
breathing slow, body temperature
drops, enters a sleep-like state
 Hedgehogs: Usually, hedgehogs maintain a constant body
temperature, i.e 35 degree centigrade, during summer but at the
onset of winter, their temperature drops to 6 degree centigrade in
order to cope with the scarcity of food. Hedgehogs go into
hibernation for about 2 to 5 months with the males hibernating
before the females.
 Badgers: They are
torpors or temporary
hibernators and in
winters they store
enough food in their
burrows, so that they
may wake up, eat and
go back to sleep again.
Badgers are omnivores,
that is they eat both
plants and animals.
Honey badgers, one of
the types of badgers are
nocturnal animals.
 Frogs and Toads: Frogs living in colder climates, hibernate in
winter in small creeks, cracks in logs and in rocky places. They
store glucose in their bodies that keeps them from getting frozen.
Some of the species of frogs even hibernate under water. Toads are
cold blooded and nocturnal creatures. Their hibernation period
begins from October and some toads are known to hibernate for
as long as three to four years. They survive on body fat that has
been stored in their bodies during the warm months.
 Moths: Moths are a species of insects that closely
resemble a butterfly. Moths hibernate in clusters and
during the winters they sleep in creeks or cracks in the
wood.
Check for Understanding:
 1. In what ways does the behavior among territorial animals differ?
 2. How does hibernation help animals to survive?
 3. Do you think that the amount of water used by each person in the
United States has changed over time? If so, in what way? Explain
your answer.
 4. Suppose a particular area was to experience a sudden change in
rainfall and temperature that lasts a long time. Do you think the
area would lose its ability to support life?
The Mississippi Flood
 Read page 41 in your textbook
 “The Mississippi Flood –Who should pay for property
damage on a floodplain?”
 Answer the decision questions fully and hand in.
The Ecosystem
 Ecosystem is a highly
organized, structured
environment that is
delicately balanced
 Ecosystems can be studied
on many levels, from
individual species to the
interactions within the entire
ecosystem.
 Includes all the biotic and
abiotic factors in an area.
Species
 A group of organisms
similar to one another, able
to breed and produce
fertile offspring
 All members have similar
needs
 Range of tolerance
 Size of territory
 Type of food
 Members often compete
with each other for
resources
Habitat
 The type of environment in
which a particular species lives
 Describe the habitat of a bird
 Describe the habitat of a fish
 Describe the habitat of a panda
 Provides appropriate food,
shelter, temperature, etc that a
species needs for survival
 Destruction of habitat is a
serious threat to the survival
of many species
Geographical Range
 The total area in which a species
can live
 Depends on the size of the area
where the habitat is suitable
 Mountain Lion
 Requires habitat with diverse
plants, large hunting territory,
variety of prey animals
 Used to roam all of continental
U.S.
 Humans took over their range
 Now restricted to western
mountains
Populations and Communities
 Population - all the members of
a species that live in the same
area
 For example:
 Ants in an ant hill
 Dandelions in a field
 Community - all the
populations that live and
interact in the same
environment
 Foe example:
 The ants and the dandelions
Ecosystem
 Includes all the
communities that live in
area as well as the abiotic
factors in that
environment
 Include water, soil,
climate
 Healthy ecosystem
contains a wide variety of
organisms
Biodiversity
 The variety of species in an
environment
 If enough of a habitat is
destroyed, the species that
live there can become
extinct
 This decreases biodiversity
and stability
 For example – tropical
rainforests
Check for Understanding:
 1.What factors are included in an ecosystem?
 2.What do you think is the geographical range for human beings?
 3. Some ancient cultures, such as the societies that live in rain forests,
are shrinking as a result of the destruction of their habitat. Do you
think human societies should be protected, as are endangered species
of plants and animals? Explain.