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Title: Systems, Matter and Energy


1
Systems, Matter and Energy
  • APES
  • September 2005

2
Miller Chapter 3Science, Systems, Matter, and
Energy
  • What is a system? What is a systems approach?
  • What are the components/behaviors of complex
    systems?
  • Basic forms of matter and energy
  • Matter and energy as a resource
  • Scientific laws governing matter and energy
  • Application of the laws of matter and energy to a
    sustainable society

3
A Brief Note About Science Terms
  • Controlled Experiment
  • Single-variable analysis
  • Dependent vs. Independent variables
  • Experimental (treatment) vs. Control Group
  • Variables to be held constant
  • Hypotheses if ___, then____ or null
  • Limitations of Environmental Science
  • A huge number of interacting variables in the
    field
  • We do not often have enough data or sufficiently
    sophisticated mathematical models to aid in our
    understanding
  • Multivariable analysis gets around this somewhat
  • Meaningful controlled experiments in the lab are
    limited by their applicability to real world
    scenarios
  • Frontier vs. Consensus Science
  • Junk science

4
What is a systems approach to science?
5
A Systems Approach to the World
  • Environment viewed and analyzed as a set of
    complex interacting systems involving living and
    non-living components
  • SYSTEMS
  • Consist of interconnected components that
    function and are linked together to form
    integrated wholes
  • The whole is always greater than the sum of its
    parts
  • Behavior is theoretically predictable
  • Is a pile of auto parts in the corner a system?
  • Emphasis in EnvSci on relationships and linkages
    between constituent parts of the whole
  • CAUTION! This reductive method can often make us
    lose sight of the forest amongst the trees

6
System Components
  • Inputs
  • Matter or energy or information
  • Flows or throughputs
  • Of matter or energy or information
  • Stores (storage areas)
  • Areas where matter, energy, or information can
    accumulate for various lengths of time before
    being released
  • Outputs
  • Of matter or energy or info that flow out of
    system into sinks in the environment
  • Boundaries or edges

7
Ecosystem as an example of a system
  • Biotic and abiotic factors interacting in a given
    area
  • What would this be in our ecocolumn?
  • Energy flows through the system Matter recycles
    within it
  • Photosynthesis fixes suns energy and passes it
    on to animals?eventually released as heat that is
    radiated off into space
  • Energy flows
  • Carbon (matter) is also fixed from carbon
    dioxide and carbohydrates?passes through several
    organisms before reaching the atmosphere from
    whence it will again be extracted by
    photosynthesizing plants
  • Cycling of carbon from one sink to another

8
Types of Systems
  • Open
  • Exchanges matter and energy across its boundaries
    with its surroundings
  • Example almost all ecosystems are open (IB
    handout fig2)
  • Organisms, organ systems, cells, etc
  • Closed
  • Energy (but not matter) is transferred between a
    system and its surroundings
  • Do not occur naturally on earth but earth itself
    comes close
  • Biosphere II project attempted to simulate it
  • Energy enters as sunlight departs as IR radiation
    (HEAT!)
  • Isolated
  • Exchanges neither matter nor energy
  • Can not exist naturally with exception of whole
    universe as a system

9
Properties of Complex Systems
  • Open-ness
  • Nested (a person is made of cells)
  • Homeostasis or equilibrium
  • Feedback loops (positive negative)
  • Time delays (lag effects)
  • Discontinuities
  • Synergismsnon linear dynamics

10
System Equilibrium or homeostasis
  • Static Equilibrium
  • No change properties remain constant over time
    condition to which natural systems can be
    compared to
  • Steady-State Equilibrium
  • Common to most open systems in nature
  • Although there is continual input and output of
    matter and energy, the state of the system
    remains constant
  • Population may go up or down but remains
    relatively constant
  • Example of homeostasis in mammals within a degree
    or two of normal is a great example
  • Predator prey numbers is another good example
  • Stability the tendency of the system to return
    to its original equilibrium following disturbance
  • As opposed to adopting a new equilibrium

11
What would be considered stability in our
ecocolumn?
12
How is homeostasis achieved?
  • Feedback Loops
  • A portion of output signal is fed back as an
    input
  • Can either reinforce or slows the original change
  • ExampleAn output of energy or matter is fed
    back into the system as an input that changes the
    system

13
Positive and Negative Feedback Loops
  • Positive Feedback Loops (think of examples)
  • A change in a certain direction causes the system
    to change further in the same direction
  • Accelerate the transformation in the same
    direction as the preceding results
  • Results are cumulativeresults in exponential
    growth or decline
  • Increases the deviation from the normdeadly in
    living systems
  • Destabilize system (runaway cycle)
  • Negative Feedback Loops
  • A change in a certain direction causes the system
    to lessen that changecounteracts deviation from
    the norm (stabilizes system)
  • Often involve time lagsproblems may build to a
    threshold and cause a fundamental change in the
    behavior of the system (Discontinuity)

14
Positive and Negative Feedback
15
An Example of Various Feedback Loops
16
Examples of Feedback LoopsSee Gore In Class
Handout
  • Global Warming and ozone depletion
  • GW accentuates ozone depletion b/c it increases
    ice clouds in the stratospherewith less ozone,
    phytoplankton are able to draw down less CO2
    causing more warming
  • Overuse of pesticides (pesticide resistance)
  • Global Warming
  • As frozen tundra thaws, methane is released.
    More methane means more warming
  • As frozen tundra thaws, less light is reflected
    back into spaceless reflected light means more
    is absorbed which means more warming.

17
Complex System Behaviors
  • Time delays (lag effects)
  • Complex systems often show time delays between
    the input of a stimulus and the response to it
  • Smoker gets cancer 30 years later (Corrective
    actions may come too late!)
  • Discontinuities
  • Time lags allow a problem to build up slowly
    until it reaches a threshold level and causes a
    fundamental change in the behavior of the system
  • Synergistic Interactions
  • Deviations from additive or linear behavior

18
Discontinuities
  • Non linear systems can maintain dynamic
    equilibrium in the face of disruptionsbut only
    to a certain tipping point
  • Then, even small shifts in their balance can
    cause critical changes that throw the system into
    disequilibrium from which it may never return to
    its original pattern
  • Example
  • Global warming may trigger a localized ice age
  • Introduction of an exotic species totally changes
    an ecosystem

19
Synergisms
  • Two or more environmental processes interact in
    such a way that the outcome is not additive but
    multiplicative
  • A plant with reduced sunlight is more susceptible
    to the effects of cold weather
  • The toxic effect of two drugs is greater than the
    toxic effects of each individual drug

20
Relationship between Complexity and Stability
  • Many argue these ideas are closely coupled
  • The more complex a system is, the more energy
    paths, feedback loops, and synergistic links
    there are
  • A system with a multitude of links can withstand
    stress or change better than one with only a few
    components
  • Railway example (single derailmentchaos)
  • Biodiversity thus becomes a component of
    ecosystem stability
  • Old growth forest vs Tree Plantation
  • House of cards analogy

21
Models of Systems
  • Mathematical Models
  • Describe behavior of complex systems (weather)
  • Predict future behavior of complex system
  • Find out how systems work
  • Simulations/approximate representations of real
    system such as microcosms/macrocosms
  • Can gain insight into the interactions of
    multiple variables
  • Despite its usefulness, a model is no more than a
    set of hypotheses or assumptions about how we
    think a certain system works
  • No better than the assumptions or the data that
    they are based upon

22
Limitations of System Models
  • Models are weak if
  • Too many interacting variables (SYNERGISMS)
  • Extrapolate from too small a sample size
  • Consequences of actions have delays
  • Consequences chain react (one leads to another to
    another)
  • Responses vary temporally/spatially
  • Not enough proper controlled experiments to get
    reliable data to model

23
Matter and Energy Form and Structure
  • Review of basic physics/chemistry
  • Building Blocks
  • Atoms (protons neutrons electrons) atomic
    pH scale, mass number elements isotopes ions
    compounds
  • Covalent vs ionic bonds
  • Organic vs Inorganic compounds
  • Hydrocarbons chlorinated hydrocarbons (DDT)
    chlorofluorocarbons (CFC) carbohydrates
    proteins nucleic acids genes chromosomes
  • Inorganic no carbon-carbon or carbon-hydrogen
    bonds
  • NaCl, water, CO, CO2, SO2, NH3 etc

24
Matter Quality
  • High Quality
  • Concentrated usually found near earths surface
  • Great for use as a resource
  • Aluminum can is more concentrated than aluminum
    orethats why it takes less energy to recycle!
  • A cube of sugarvs. sugar dissolved in water
  • Low Quality
  • Dilute Deep underground or dispersed in the
    ocean or atmosphere
  • Little potential for use
  • E.g. gold in seawater
  • Material Efficiency or Resource Productivity
  • 2-6 of matter ends up providing useful goods and
    services (we need to shoot for 75-90)

25
Forms of Matter (Fig 3-7)
26
Energy Forms
  • Capacity to do work and transfer heat
  • Kinetic or potential
  • Kinetic is energy that matter has because of its
    mass and speed
  • Wind, streams, electricity, heat flowing from
    high to low temperature
  • Potential is stored energy available for use
  • Unlit stick of dynamite, water behind a dam,
    chemical energy stored in gasoline molecules, a
    bike on the top of a hill, energy stored in the
    nuclei of atoms
  • Potential energy can become kinetic energy
  • Potential energy is bonds of gasoline molecules
    get turned into heat, light, and mechanical
    (kinetic) energy that propels the car

27
Energy Quality
  • High-Quality (low entropy)
  • Organized and concentrated and can perform much
    useful work
  • Electricity, chemical energy of coal or gasoline,
    concentrated sunlight, uranium-235, high velocity
    wind, very high temperature heat food
  • Low-Quality (high entropy)
  • Disorganized and dispersed with little ability to
    do useful work
  • Heat dispersed in moving molecules of matter
  • Total amount of heat in Atlantic Ocean gt High
    quality energy of the oil of Saudi Arabia, yet
    too dispersed to do much with

28
Energy Quality (Fig 3-9)
29
Physical and Chemical Changes
  • Physical Change
  • No change in chemistry
  • States of water
  • Chemical Change
  • Composition of elements or compounds altered
  • Exothermic vs Endothermic
  • Nuclear Changes
  • Natural radioactive decay
  • Unstable isotopes emit matter or radiation at a
    fixed rate
  • Gamma rays (high energy electromagnetic
    radiation)
  • Alpha and beta ionizing particles
  • Fission (split apart nuclei?chain reaction)

30
Physical Chemical Changes
31
Law of Conservation of Matter There is no away
  • Matter is neither created nor destroyed
  • In chemical reactions, bonds are broken, atoms
    rearranged, and bonds reformed but in no way is
    matter either created nor destroyed
  • Implications
  • You can not make something from nothing
  • We do not consume matterinstead we only use
    resources for a whilematter goes from high to
    low quality.
  • Natural resources are transformed though the
    production process into something of use for
    humans?however, this product will eventually
    disintegrate, decay, fall apart, or dissipate
    into something useless
  • Everything we have thrown away is still with us
    in one form or another
  • We can make the environment cleaner and convert
    some potentially harmful chemicals into less
    harmful forms but we will always have to face the
    issue of where our wastes go

32
Ecosystem Implications of the First Law
  • The biotic and abiotic components of an ecosystem
    are linked together by matter recycling. 
  • There is very little matter wasted in natural
    ecosystems.

33
Laws of Energy First Law of Thermodynamics
  • Basically the Law of Matter applied to energy
  • 1 Energy is neither created nor destroyed but
    may be converted from one form to another
  • i.e., It takes energy to get energy!
  • There is no free lunch!
  • Cant get something for nothing
  • The quantity of energy does not change but the
    quality does
  • high quality to low quality
  • aka low entropy to high entropy

34
Entropywhat is it?
  • From the Greek word for transformation
  • Entropy is a one way street of irreversible
    change
  • An irreversible movement towards less ordered
    states of matter and energy
  • A continual increase in the disorder of the
    universe
  • Sugar cube vs. dissolved sugar
  • DictionaryA measure of the unavailable energy
    in a system
  • Unavailable means unavailable to do work

35
Laws of Energy Second Law of Thermodynamics
  • In an isolated system, the level of entropy
    (think of this as used-up-ness) or disorder
    increases in an isolated system
  • In every energy transfer, some of the high
    quality energy is used and degraded to a lower
    quality form
  • Energy (and matter) always go from a more useful
    to a less useful form (move towards higher
    entropy (more disorder)
  • Implications of the Second Law
  • We always end up with less usable energy than we
    started with (can never get out more than you put
    in!)
  • In fact, you cant even break even!
  • No energy exchange is perfectly efficient
  • There is no perpetual motion machine
  • This is why food-chains rarely have more than 5
    links
  • Energy flow through an ecosystem is characterized
    by an ecological efficiency that varies from 5
    to 20.

36
Putting it all together
  • Although matter and energy are constant in
    quantity (1st law), they change in quality
  • The measure of matter/energy quality is
    entropyThe amount of entropy is always
    increasing in an isolated system (2nd law)
  • Thus, there is a flow of matter and energy from
    highly useful (low entropy) sources to less
    useful (high entropy) sinks.
  • We can therefore recycle matterbut never 100
  • We can not recycle energy b/c it always takes
    more energy to do the recycling than the amount
    that can be recycled
  • Therefore, energy flows through, matter cycles
    within!!!
  • SUMMARY OF THE SUMMARYLow entropy (high
    quality) raw materials and energy are used to
    create high entropy (low quality) waste and
    unavailable energy

37
The Hourglass Metaphor
Who can explain this one?
38
Energy Efficiency
  • A measure of how much useful work is accomplished
    per unit input of energy
  • 16 of energy in US ends up performing useful
    work
  • 84 is unavoidably wasted
  • 41 is unavoidably lost due to the second law of
    thermodynamics
  • 43 is unnecessarily wasted by inefficiencies in
    business and society
  • Remember 2nd Law Energy always goes from high
    to low quality
  • Car (10 of chemical energy is converted to
    mechanical)
  • Regular light bulb (5 light 95 heat)
  • This applied to ecosystems is ecological
    efficiency (see ch. 4)

39
Connection to EconomySee thermodynamic reading
  • High-throughput economy
  • High waste economy that attempts to sustain
    ever-increasing economic growth by increasing the
    flow of matter and energy resources through their
    economic system
  • Exceed capacity of environment to deal with waste
    and absorb wasted heat
  • In 1990, the average American's economic and
    personal activities mobilized a flow of roughly
    123 dry weight pounds of material per day...this
    includes 47lbs of fuel, 46lbs of construction
    material, 15lbs of farmland, 6lbs of forest
    products, 6lbs of industrial minerals, and 3lbs
    of metals...In sum, Americans "use" nearly 1
    million pounds of materials per person per
    year...
  • Matter-recycling Economy
  • Allow economic growth to continue without
    depleting natural resources or producing
    excessive pollution or environmental
    deterioration
  • Buy us some time but rememberit does not allow
    for more and more people to use more and more
    resources indefinitely, even if all of them were
    perfectly recycled

40
High Throughput Economy
41
Lessons From Nature Low Throughput Economy
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