Transcript Ecosystems and Energy

Ecosystems and
Energy
Part 1
Chapter 4
Environment 4th ed.
Raven & Berg
Life on Earth depends on three
interconnected factors:
 The one-way flow of high quality energy
sun
living things (feeding interactions)
environment (low quality energy)
back into space as (infrared radiation - heat).
 Cycling of matter or nutrients through parts of
the biosphere.
 Gravity which allows the planet to hold on to its
atmosphere and causes the downward
movement of chemical in the matter cycles.
The Sun
 Supplies energy for photosynthesis
 Powers the cycling of matter
 Drives the climate and weather systems
that distribute heat and fresh water over
the Earth’s surface.
 Provides the natural green house effect
Vocabulary to begin..
 Abiotic – non-living
 Biotic – living
More Vocabulary…
 Levels of biological
organization
 Figure 4.1 page 65
 Mini-glossary
page 64
More Vocabulary…
 Ecology – the study of interactions
among organisms and between
organisms and their abiotic environment.
Earth’s Four Realms
 Hydrosphere – Earth’s supply of water
liquid and frozen, fresh and salty
 Atmosphere – gaseous envelope
surrounding the earth
 Lithosphere – soil and rock of Earth’s
crust
 Biosphere – all living organisms
Let’s Practice
What is the word for…
 A group of individuals of the same
species that occupy a common area.
 The unique environment that organisms
are best adapted to energy resources.
 One individual living thing.
 Where an organism lives.
 A group of organisms that are able to
produce fertile offspring.
Let’s Practice
What is the word for…
 A physically distinct, self-supporting unit
of interacting organisms and their
environment.
 Means living.
 A group of interacting populations of
different species
 Means non-living.
Energy Quality is..
the measure of an energy sources’
ability to do useful work
 Entropy: a measure of disorder or
randomness of a system
Types of Energy Quality
 High quality: organized or concentrated
and can perform much useful work.
 Examples…
electricity nuclear energy solar energy
Types of Energy Quality
 Low quality: disorganized or dispersed
and has little ability to do useful work.
 Example…
heat in
the ocean
Forms of Energy
Potential vs. Kinetic
stored energy vs. energy of motion
 Mini-Glossary page 67
 Units
kilojoules, kJ unit of work
kilocalories, kcal unit of heat
Closed vs. Open System
 The earth is an open system for energy.
We receive energy from the sun and heat
energy is released back into the
universe. We exchange energy with our
surroundings.
 The earth is a closed system for matter.
Matter is never created or destroyed. All
matter that is here has always been here.
Are you breathing the same oxygen
atoms the dinosaurs breathed???
Two Laws of Energy
 1st Law of Thermodynamics – Energy is
neither created or destroyed but can be
transformed from one form to another.
 2nd Law of Thermodynamics – Whenever
energy is converted from one form to another,
some usable energy (energy available to do
work) is degraded into heat (a less usable form
that disperses into the environment.)
*** Because of this, the amount of usable energy
available to do work decreases over time.
Example…
 When a car is driven, only about 20% of
the high-quality energy available in its
gasoline fuel is converted into
mechanical energy (to propel the vehicle)
and electrical energy (to run its electrical
systems). The remaining 80% is
degraded to low-quality heat that is
released into the environment and
eventually lost into space.
Example…
 When electrical energy flows through
filament wires in an incandescent light
bulb, it is changed into about 5% useful
light and 95% low-quality heat that flows
into the environment. In other words, this
so called light bulb is really a heat bulb.
Energy Efficiency
 A measure of how much useful work is
accomplished by a particular input of
energy into a system.
 ENERGY CAN NEVER BE RECYCLED
OR REUSED. IT IS ALWAYS
TRANSFORMED FROM HIGH QUALITY
TO LOW QUALITY ENERGY
Let’s Practice…
 Give an example of entropy.
 Energy quality is a measure of an energy
sources’ ability to do useful work. What
is the difference in high quality energy
and low quality energy? Give an
example.
 What are three interconnected factors
that life on Earth depends?
Let’s Practice
 State the 1st and 2nd Laws of Energy
(thermodynamics).
 Someone wants you to invest money in
an automobile engine that will produce
more energy than the energy in the fuel
(such as gasoline or electricity) you use
to run the motor. What is your response?
Explain.
Let’s Practice…
 Use the 2nd energy law to explain why a
barrel of oil can be used as a fuel only
once?
 Why do you continuously need to eat
food?
Vocabulary to know..
 Photosynthesis  Cellular respiration
 Hydrothermal vents
 Page 69-70