Transcript The Earth`s Spheres

Unit 2 – Natural Systems
The Earth’s Spheres and
Ecosystems
The Earth’s Spheres
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Looking at the following components:
Lithosphere
Hydrosphere
Atmosphere
Biosphere
Open System
Closed System
The Earth’s Spheres
• Lithosphere is the solid outer crust of the
earth
• The lithosphere runs up to 60 miles deep, is
divided into the crust and upper mantle.
– The upper part of the crust is made of igneous
and sedimentary rocks; this makes up the
continents.
– The lower crust is made of igneous rocks which
form the ocean floors.
• The inner layers of the earth are the mantle
and the core
The Earth’s Spheres
• Lithosphere is the outer part of the earth,
consisting of the crust and upper mantle.
The Earth’s Spheres
• Hydrosphere is the part of the Earth
composed of water (including clouds,
oceans, seas, ice caps, glaciers, lakes,
rivers, underground water supplies, and
atmospheric water vapour).
• Approximately 71% of the Earth is covered
by water.
– 97% of this water is in the oceans (salt water)
– 3% is freshwater
• 77% of freshwater is locked in ice
• 22% of freshwater is in the ground
• <1% of freshwater is in lakes, rivers, and wetlands
Hydrosphere
The Earth’s Spheres
• Atmosphere is the mixture of gases
surrounding the Earth and other planets.
– Thermosphere
– Mesopause
– Mesosphere
– Stratopause
– Stratosphere
– Tropopause
– Troposphere
The Earth’s Spheres
• Biosphere is the life zone of the Earth and
includes all living organisms, including
man, and all organic matter that has not
yet decomposed.
• The biosphere is structured into a
hierarchy known as the food chain
whereby all life is dependent upon the first
tier (i.e. mainly the primary producers that
are capable of photosynthesis).
Biosphere con’t…
• All organisms are intrinsically linked to
their physical environment and the
relationship between an organism and its
environment is the study of ecology.
• The biosphere can be divided into distinct
ecosystems that represent the interactions
between a group of organisms forming a
trophic pyramid and the environment or
habitat in which they live.
The Earth’s Spheres
• Biosphere is the combination of the
lithosphere, hydrosphere, and atmosphere
that can support life.
The Earth’s Systems
• It is important to understand how the various
parts of our Earth’s systems interact in order to
create solutions for environmental problems.
• An open system is one where both energy
(heat) and matter can be exchanged (e.g.
oceans – water is evaporated into atmosphere)
• A closed system is one where only energy
(heat) can be exchanged (e.g. soil/land – heat
absorbed and released during day and night)
Ecosystems
Key Terms…
• Ecosystem: all different organisms living in a certain
area along with their physical environment
e.g. Soil ecosystem (earthworms, snakes, moles,
insects, plants, fungi and bacteria)
* Think of an ecosystem like a car, everything in a car
works together to make it work, if one part breaks the car
might not work!
• Abiotic: the non-living parts of an ecosystem
e.g. Temperature, sunlight, humidity, minerals, water
supply and soil type
• Biotic: the living parts of an ecosystem which interact
with one another as well as the abiotic factors
e.g. Plants, animals and microorganisms
How Does an Ecosystem Fit Into
the Organization of Living Things?
An individual
organism is
part of
a population,
a community,
an ecosystem,
and the
biosphere.
Ecosystems
Key Terms…
• Organism: one individual living thing
e.g. a person, ant, gorilla, flower, bacterium
• Species: a group of organisms that are able to produce fertile
offspring, that share common genes and therefore resemble
each other
e.g. Humans are of the species Homo sapiens
Domestic dogs are of the species Canis familiaris
• Populations: a group of individuals of the same species living
in a particular place
e.g. Bullfrogs in a pond, lions in a savanna, flowers in a field
• Communities: consists of a group of interacting populations of
different species of organisms
e.g. All living inhabitants of an ecosystem make up a community
Pond - includes populations of fish, plants, insects,
amphibians, and microorganisms
Ecosystems
Key Terms…
• Niche: an organism’s way of life including all
interactions with both living and non-living parts of its
environment (lifestyle)
e.g. A lion’s niche might include:
a) a tick on the lion’s face
b) the lion fighting with hyenas
c) the lion feeding on prey
d) the lion drinking at the water hole
• Habitat: the actual place an organism lives
e.g. Cactus – desert, Water Lily - pond
Ecosystems
Are Made Up Of
Abiotic Parts such as…
Biotic Parts such as…
Habitats
Sunlight
which live in
Temperature Water
Organisms
which are a part of
which act in
Niches
Populations
which are a part of
Communities
Flow of Energy
• Photosynthesis: biological synthesis of chemical
compounds in the presence of light; produces organic
substances such as sugar
e.g. the way plants produce energy
• Respiration: breaking down food to yield energy
e.g. you eat food, your body uses the oxygen you
breathe to break down food molecules releasing energy