Topic 1 systems & models

1.1.1 Systems and Synergy
Guru IB ESS SYSTEMS & MODELS
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What do these pictures, have in common?
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They are all Systems
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What is the meaning of the word system?
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A system is something that:
1.Is made up of individual component parts that work together to perform a particular function
2. A bicycle is an example of a system
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But if the parts of the bicycle are piled up in the middle of the room, they cease to work together and thus stop being a system.
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So a system could be...?
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•A building
•a flower
•an atom
•a political party
•a car
•your body
•furniture
•an electric circuit
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What is the use of Systems Concept
Why do we use Systems?
•Useful for understanding and explaining phenomena
•A holistic approach that can lead to a deeper understanding and possibly to further discoveries
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k.kumar@pathways.in
•gurucharankumar16@gmail.com
•9650834269
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SYNERGY
• One of the most fascinating characteristics of any and all structures is the characteristic called SYNERGY
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WHAT IS SYNERGY?
•A state in which two or more things work together in a particularly fruitful way that produces an effect greater the sum of their individual effects.
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EXAMPLE OF SYNERGY
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Another example of synergy
•Ordinary Table Salt (NaCl, Sodium Chloride)
•Synergy: The behaviour of whole systems that is unpredicted by knowing the behaviour of the individual parts taken separately
• Na (sodium) is a metal, highly reactive in water, explosive, burns with a yellow flame.
•Cl (chlorine) is a deadly greenish gas.
•Both of these elements when taken separately are poisonous and deadly BUT
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SALT
•When combined, we witness synergy. Two deadly substances combine to produce something that we cannot live without.
•Something unique and new and unpredictable happens when two or more things come together and work together
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Atoms combine together to form structural systems
1.The behaviour of the table salt is totally unpredictable by simply knowing the behaviour of the individual parts.
2.All nature, all systems, all structures display synergy. The Universe is the Synergy of Synergies.
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Another way to say this is :
•Even if you know all the parts that make up a system you still cannot know or even predict how the whole system is going to behave or work.
•Can you give an example of this??
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The Human Body
1.If you take all the stuff that makes up a person, you would find that we are made up of:
2.Hydrogen, Nitrogen, Oxygen, Carbon, Water, Calcium, Sodium, Magnesium, Sulfur, Iron and many other elements. The total cost of all of these things at the store is about……????
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Even if you looked at the next level up…the Cell
1.Even if you knew what all the cells in your body do, you still could not describe YOU.
2.Something very unique and new and unpredictable happens when the parts of a system work together.
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Discovery
•One great truth about discovery is that, “One discovery often leads to further discoveries”
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Bring different ideas Together
•One of the best places to find ideas for structural systems is in NATURE.
•Nature always uses the most economical, efficient and reliable structural systems
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What is a Model?
What is a model?
•A representation or a simulation, could be conceptual, physical, mathematical
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Why Models
Why models?
•The real thing is not available or it’s impractical
•Too rare, too complex, too big, too expensive
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How to evaluate a model?
•Does it explain past observations
•Does it agree with other models
•Does it predict accurately
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RECAP
•What is SYSTEM?
•Examples of SYSTEM?
•Why do we use Systems?
•What is SYNERGY?
•Examples of SYNERGY?
•What is MODEL?
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Ecosystems Ecological Systems
•Ecological Systems follow the laws of synergy as well.
•It is the interrelationships between the parts that produces the behaviour of the whole.
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Environmental Systems and Societies
Interrelationships among climate, geology, soil, vegetation, and animals.
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What is ENERGY?
•Energy is defined as the ability or the capacity to do work.
•Energy causes things to happen around us
•Energy lights our cities, powers our vehicles, and runs machinery in factories. It warms and cools our homes, cooks our food, plays our music, and gives us pictures on television.
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What is MATTER?
•Matter is generally considered to be anything that has mass and volume
•Example:
•a car would be said to be made of matter, as it occupies space, and has mass.
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1.1.1.Outline the concept and characteristic of systems
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TYPES OF SYSTEM
1.OPEN SYSTEM
2.CLOSED SYSTEM
3.ISOLATED SYSTEM
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1. OPEN SYSTEM: a system in which both matter and energy are exchanged across boundaries of the system.
Systems are defined by the source and ultimate destination of their matter and/or energy.
Most natural living systems are OPEN systems.
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2. CLOSED SYSTEM: a system in which energy is exchanged across boundaries of the system, but matter is not. Example-Aquarium & Terrarium
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A small enclosure or closed container in which selected living plants and sometimes small land animals, such as turtles and lizards, are kept and observed.
Terrarium
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3. ISOLATED SYSTEM: a system in which neither energy nor matter is exchanged with its envioronemt.Do not exist naturally
NO SUCH SYSTEM EXISTS!!!
Example:Space Station(artifical)
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CLOSED SYSTEM
CLOSED SYSTEM
CLOSED SYSTEM
OPEN SYSTEM
OPEN SYSTEM
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Components of a system:
1.Inputs such as energy or matter.
Calories
Protein
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2. Flows of matter or energy within the systems at certain rates.
Calories
Protein
Calories
Protein
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3.Outputs of certain forms of matter or energy that flow out of the system into sinks in the environment.
Calories
Protein
WasteHeat
WasteMatter
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4. Storage areas in which energy or matter can accumulate for various lengths of time before being released.
Calories
Protein
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RECAP
•What is open system? Example
•What is closed system? Example
•What is Isolated system? Example
•Components of a system
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Two basic processes must occur in an ecosystem:
1.A cycling of chemical elements.
2.Flow of energy. Energy flows through systems while materials circulate around systems.
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1.1.7 Desccribe transfer and transformation processes
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TRANSFERS OF ENERGY
TRANSFORMATTION OF ENERGY
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What are transfer process
•A transfer is a process where there is a change in location within the system, but there is no change in state.
Example:
•Water is falling from clouds to the ground as rain.
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CLOUDS IN THE FORM OF WATER
OCEAN
CHANGE IN LOCATION
STATE
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What are transformation process?
•Transformation are process that leads to the formation of new products or change in state
Example:
•Evaporation of water from a lake into the atmosphere
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•Transfer are process that lead to a change in location but not a change in state
•Transformation are process that leads to the formation of new products or c change in state
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Describe Transfer and Transformation
•Transfer - just a movement from one place to another ….water mountain to ocean..
•Transformation - actual change of state or material -- liquid water/evaporates… CO2 to sugars/starch in plant .
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Transfer vs. transformation
•Transfer involves a change in location
–e.g. water falling as rain, running off the land into a river then to the sea
•Transformation involves a change in state
–e.g. evaporation of water from a lake into the atmosphere
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AUGUST FORMATIVE & SUMMATIVE
•FORMATIVE WORKSHEET-20 MARKS
•Due date:3.09.2012
•SUMMATIVE-CHART -20 MARKS
•Topic-3 types of systems with suitable examples
•Due date:31.08.2012
58

TRANSFERS OF ENERGY
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ENERGY TRANSFORMATIONS
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1.1.8 Distinguish between flows and storage in relation to systems
•Flows :Flows are movements from one place to another in the system and are shown by arrows
•Flows are either inputs or outputs.
•Inputs are movements into a storage and outputs are movements out of a storage
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•Storages are where something in a system and are shown by boxes
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Inputs and Outputs
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1.1.4. Thermodynamics nutrient cycles
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1.Thermodynamics is the study of the energy transformations that occur in a system.
2.It is the study of the flow of energy through nature.
3.Within a system energy cannot be re-used.
What is Thermodynamics?
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•The study of thermodynamics is about energy flow in natural systems
•The Laws of Thermodynamics describe what is known about energy transformations in our universe
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•Two laws
•First Law of Thermodynamics
•Second Law of Thermodynamics
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1st Law of Thermodynamics
•States that energy can be transferred and transformed,
but it CANNOT be created nor destroyed.
•Law of Conservation of Energy.
•Energy of the universe is constant.
Guru IB ESS
SYSTEMS & MODELS
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First Law of Thermodynamics
ENERGY 2
PROCESS
ENERGY 1 (WORK)
ENERGY 3
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In Ecosystem where you can apply first law
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Photosynthesis: an example of the First Law of Thermodynamics: Energy Transformation
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Photosynthesis is the First Law of Thermodynamics
Heat Energy
Light Energy
Chemical Energy
Photosynthesis
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Thermal equilibrium = inpuGtsu rue q u a l o u tIBp EuStSs o v e r a long period of time.
SYSTEMS & MODELS
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Sun
Producers (rooted plants)
Producers (phytoplankton)
Primary consumers (zooplankton)
Secondary consumers (fish)
Dissolved chemicals
Tertiary consumers (turtles)
Sediment
Decomposers (bacteria and fungi)
Energy at one level must come from previous level
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Answer this………………..
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Using the first law of thermodynamics explain why the energy pyramid is always pyramid shaped (bottom bigger than top)
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2nd Law of Thermodynamics
1.The Second Law is the Law of Entropy(disorder, randomness or chaos).
2.It is essential state that as energy is transformed from one state to another state ,the conversion is never 100% efficient and therefore energy is always lost to that system
3.Every energy transformation or transfer results in an increase in the disorder of the universe
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•In any spontaneous process the energy transformation is not 100 % efficient, part of it is lost (dissipated) as heat which, can not be used to do work (within the system) to fight against entropy.
•In fact, for most ecosystems, processes are on average only 10% efficient (10% Principle), this means that for every energy passage (transformation) 90% is lost in the form of heat energy, only 10% passes to the next element in the system.
•Most biological processes are very inefficient in their transformation of energy which is lost as heat.
The Second Law of Thermodynamics can also be stated in the following way:
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What results from the second law of Thermodynamics?
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The Second Law of Thermodynamics in numbers: The 10% Law For most ecological process, theamount of energy that is passed from one trophic level to the next is on average 10%.
Heat Heat Heat
900 J 90 J 9 J
Energy 1 Process 1 Process 2 Process 3
1000 J 100 J 10 J 1 J
J = Joule SI Unit of Energy
1kJ = 1 Kilo Joule = 1000 Joules
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Second Law of Thermodynamics
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•Any conversion is less than 100% efficient and therefore some energy is lost or wasted.
•Usually this energy is lost in the form of HEAT (= random energy of molecular movement). We usually summarize it as respiration.
Solar energy
Waste heat
Chemical
energy
(photosynthesis)
Waste heat
Waste heat
Waste heat
Chemical energy (food)
Mechanical energy (moving, thinking, living)
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Only 25% of chemical “E” stored in gasoline is transformed in to motion of the car and 75% is lost as heat!!
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Without adding energy to a system, the system will break down .
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Primary Producers and the 2nd law of Thermodynamics
(Output)
(Output)
(Output)
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Consumers and the 2nd law of Thermodynamics
10% for growth
2850 kJ.day- 1 Food Intake
Respiration
2000 kJ.day-1
565 kJ.day-1 Urine and Faeces
How efficient is the cow in the use of the food it takes daily?
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The Ecosystem and the 2nd law of Thermodynamics
Heat
Heat
Heat
Heat
Heat
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RECAP
•What is First law of thermodynamics?
•What is second law of thermodynamics?
•Another name of First law
•Another name of second law
•Tallest flower
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Why both the laws are important in ecosystem or environment?
•Both the laws are important because when analyzing the energy transfers in an ecosystem and living organism is general
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•1.One way energy enters an ecosystem is as sunlight. This sunlight energy is then changed into biomass by photosynthesis.
•2.That is photosynthesis captures sunlight energy and transforms it into chemical energy.
•3.Chemical energy in producers may be passed along food chain as biomass or given off as heat during respiration
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•4.Available energy is used to do work such as growth, movement and making complex molecules.
•5.All the energy leaves the ecosystem as heat. No new energy has been created.
•6.It has simply transformed and passed from one form to another.
•7.Although matter can be recycled, energy cannot and once it has been lost from the system in the form of heat it cannot made available again.
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RECAP
•What is First Law of Thermodynamics
•What is Second Law of Thermodynamics?
•What is EQUILIBRIUM?
•Three types of equilibrium
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What is Equilibrium
•Equilibrium is the tendency of the system to return to an original state following disturbance, a state of balance exists among the components of that system.
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3 TYPES
1.STEADY –STATE EQUILIBRIUM
2.STATIC EQUILIBRIUM
3.STABLE & UNSTABLE EQUILIBRIUM
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STEADY –STATE EQUILIBRIUM EXAMPLE
If these birth & death rates are equal there is no net change In population size
birth
death
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WHERE YOU CAN SEE STEADY –STATE EQUILIBRIUM IN ECOSYSTEM
QUESTION
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Food chain & Food web are the example of Steady –State Equilibrium
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Steady –State Equilibrium
•A Steady –state equilibrium is a characteristic of open system where there are continuous inputs and outputs of energy and matter, but the system as a whole remains in a more or less constant state.
•Most open systems in nature are in steady- state equilibrium.
•This means that even though there are constant inputs and outputs of energy and matter there is overall stability within the system.
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Rate of water entering = Rate of water leaving Hence the level of water is constant
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STATIC EQUILIBRIUM
•Static Equilibrium in which there is no change over time
•The force within the system are in balance, and the components remain unchanged in their relationship.
•In Static Equilibrium there are no inputs or outputs of matter or energy and no change in the system over time.
•No natural system are in static equilibrium because
all natural system have inputs and outputs of energy and matter
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let us consider two children sitting on a see- saw. At balance point (i.e., the equilibrium position) no movement of children on the see- saw occurs.
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QUESTION
WHERE YOU CAN SEE STATIC EQUILIBRIUM IN ECOSYSTEM
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•Most non living system are in Static Equilibrium
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STABLE & UNSTABLE EQUILIBRIUM
•In a stable equilibrium the system tends to return to the same equilibrium after a disturbance
•In an unstable equilibrium the system returns to a new equilibrium after disturbance
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STABLE EQUILIBRIUM
UNSTABLE EQUILIBRIUM
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FOREST FIRE -DISTURBANCE
AFTER DISTURBANCE
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RECAP
•What is First Law of Thermodynamics
•What is Second Law of Thermodynamics?
•What is EQUILIBRIUM?
•Three types of equilibrium
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RECAP
1.What is Equilibrium
2.STEADY –STATE EQUILIBRIUM
3.STATIC EQUILIBRIUM
4.STABLE & UNSTABLE EQUILIBRIUM
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SELF ASSESSMENT TEST
•What is the difference between a steady state equilibrium and a static equilibrium?
•Which type of equilibrium applies to ecological systems and why?
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•1.1.6 Define and explain the principles of positive feedback and negative feedback.
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What is FEEDBACK?
•Feedback occurs when part of the output from a system returns as input , in order to influence later outputs.
•This is also called FEEDBACK LOOP
PROCESS
FEEDBACK
INPUT
OUTPUT
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The sense of cold is the information, putting on clothes or heating up is the reaction
cold
clothes
heating up
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Respond Positively in the class
Showing interest
Teacher is successful
POSTIVE FEEDBACK
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NEGATIVE FEEDBACK
Respond negatively in the class
Showing distraction
Methodology is not appropriate
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1Positive and Negative Feedback
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Walking in hot sun, temperature rises
Body will lose heat
ONE ACTION IS INCREASING
ONE ACTION IS DECREASING
Negative feedback systems
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Negative feedback systems
•Negative feedback systems include a sequence of events that will cause an effect that is in the opposite direction to the original stimulus and thereby brings the system back to its equilibrium position.
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Example of Negative Feedback
•Predator/prey relationships
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•Predator/prey relationships are usually controlled by negative feedback where:
The increase in prey  increase in predator decrease in prey decrease in predator increase in prey---and so on in a cyclical manner.
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The classic study in Northern Canada between the Wild Cat and the hare populations is famous for its regular 11 year cycle of rising and falling populations.
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Negative feedback
•Predator Prey is a classic Example
–Snowshoe hare population increases
–More food for Lynx  Lynx population increases
–Increased predation on hares  hare population declines
–Less food for Lynx  Lynx population declines
–Less predation  Increase in hare population
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CLOSED CANOPY IN
RAINFOREST
WIND BLOWS DOWN OLD TREE
MORE LIGHT AT THE FOREST FLOOR
GROWTH OF YOUNG TREES
YOUNG TREES COMPETE FOR LIGHT AND TO REPLACE THE OLD TREE
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ANSWER THIS
•IDENTIFY THIS BIRD
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SARUS CRANE at a height of up to 1.8 m (5.9 ft)
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POSTIVE FEEDBACK
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Poor standards of education
Absence of family planning
Positive feedback
poverty
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Positive feedback
•Positive feedback includes a sequence of events that will cause a change in the same direction as the stimulus and thereby augments the change, moving the state of the system even further from the equilibrium point.
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Positive feedback
•Change leads to increasing change – it accelerates deviation
Example: Global warming
1.Temperature increases  Ice caps melt
2.Less Ice cap surface area  Less sunlight is reflected away from earth (albedo)
3.More light hits dark ocean and heat is trapped
4.Further temperature increase  Further melting of the ice
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Solar radiation
Energy in = Energy out
Reflected by atmosphere (34%)
UV radiation
Absorbed by ozone
Absorbed by the earth
Visible light
Lower stratosphere
(ozone layer)
Troposphere
Heat
Greenhouse effect
Radiated by atmosphere as heat (66%)
Earth
Heat radiated by the earth
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Most systems change by a combination of positive and negative feedback processes
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Which of the populations show positive feedback? Which of the populations show negative feedback?
I-POSTIVE FEEDBACK II-NEGATIVE III-NEGATIVE IV-POSTIVE
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WHICH IS POSTIVE & NEGATIVE
•If a pond ecosystem became polluted with nitrates, washed off agricultural land by surface runoff, algae would rapidly grow in the pond.
•The amount of dissolved oxygen in the water would decrease, killing the fish.
•The decomposers that would increase due to the dead fish would further decrease the amount of dissolved oxygen and so on...
•A good supply of grass for rabbits to eat will attract more rabbits to the area, which puts pressure on the grass, so it dies back, so the decreased food supply leads to a decrease in population because of death or out migration, which takes away the pressure on the grass, which leads to more growth and a good supply of food which leads to a more rabbits attracted to the area which puts pressure on the grass and so on and on....
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End result? Equilibrium…Recap
•A sort of equalization or end point
•Steady state equilibrium  constant changes in all directions maintain a constant state (no net change) – common to most open systems in nature
•Static equilibrium  No change at all – condition to which most natural systems can be compared but this does not exist
•Long term changes in equilibrium point do occur (evolution, succession)
•Equilibrium is stable (systems tend to return to the original equilibrium after disturbances)
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Equilibrium generally maintained by negative feedback – inputs should equal outputs
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You should be able to create a system model.
Observe the next two society examples and create a model including input, flows, stores and output
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High Throughput System Model
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High-quality energy
Matter
System Throughputs
Output (intro environment)
Unsustainable high-waste economy
Low-quality
heat
energy
Waste matter and pollution
Inputs (from environment)
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Low Throughput System Model
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High-quality energy
Matter
Pollution prevention by reducing matter throughput
Sustainable low-waste economy
Recycle and reuse
Pollution control by cleaning up some pollutants
Matter
output
Low-quality energy (heat)
Waste matter and pollution
Matter Feedback
Energy Feedback
Inputs (from environment)
System Throughputs
Outputs (from environment)
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Easter Island
What are the statues and where are the trees? A case Study in unsustainable growth practices.
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Evaluating Models
•Used when we can’t accurately measure the real event
•Models are hard with the environment because there are so many interacting variables – but nothing else could do better
•Allows us to predict likelihood of events
•But…
•They are approximations
•They may yield very different results from each other or actual events
•There are always unanticipated possibilities…
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Anticipating Environmental Surprises
•Remember any action we take has multiple unforseen consequences
•Discontinuities = Abrupt shifts occur in previously stable systems once a threshold is crossed
•Synergistic interactions = 2 factors combine to produce greater effects than they do alone
•Unpredictable or chaotic events = hurricanes, earthquakes, climate shifts
•http://www.nhc.noaa.gov/archive/2008/FAY_graphics.shtml
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What can we do?
•Develop more complex models for systems
•Increase research on environmental thresholds for better predictive power
•Formulate possible scenarios and solutions ahead of time
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Systems Measurement
Data Analysis
System Modeling
System Simulation
System Optimization
Define objectives
Identify and inventory variables
Obtain baseline data on variables
Make statistical analysis of relationships among variables
Determine significant interactions
Construct mathematical model describing interactions among variables
Run the model on a computer, with values entered for different variables
Evaluate best ways to achieve objectives
© 2004 Brooks/Cole – Thomson Learning
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Other systems examples
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Uranium 100%
Electricity from Nuclear Power Plant
14%
Resistance heating (100%)
90%
Waste heat
Passive Solar
Sunlight
100%
Waste heat
14%
Transmission
of electricity
(85%)
17%
Waste heat
Power plant (31%)
54%
Waste
heat
Uranium processing and transportation (57%)
95%
Waste
heat
Uranium mining (95%)
Energy Production
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sun
EARTH
Natural
Capital
Air; water, land, soil, biodiversity, minerals, raw materials, energy resources, and dilution, degradation, and recycling services
Economic Systems
Production
Consumption
Heat
Depletion of nonrenewable resources
Degradation and depletion of renewable resources used faster than replenished
Pollution and waste
from overloading
nature’s waste disposal
and recycling systems
Recycling and reuse
Economics & Earth
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Energy Inputs
System
Outputs
U.S. economy and lifestyles
84%
8%
4%
4%
9%
7%
41%
43%
Nonrenewable fossil fuels
Nonrenewable nuclear
Hydropower, geothermal, wind, solar
Biomass
Useful energy
Petrochemicals
Unavoidable energy
waste
Unnecessary energy waste
172

AUGUST FORMATIVE & SUMMATIVE(11B4)
•FORMATIVE WORKSHEET-20 MARKS
•Due date:31.08.2012(this Friday)
•SUMMATIVE-CHART -20 MARKS
•Topic-3 types of systems &Two types of feedback mechanism with suitable examples
•Due date:3.09.2012(next Monday)
173

Formative
•Do formative in the EVM note book
•Write page number and question for each activity
•Leave proper space for all the answers
•Use Google image and map if it is required
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Self Assessment Test
•Give two examples of negative feedback and two of positive feedback system.
•Explain why most ecosystems such as rainforest are negative feedback system
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•1.1.2 Apply the systems concept on a range of scales
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•Ecosystems provide a good example of how systems can be applied to a range of scales
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•Ecosystem can be any size from small scale to global.
•The forest itself can also be seen as an ecosystem.
•The same type of forest ecosystem may be found in many different countries with the same climatic conditions.
•When an ecosystem is looked at on a global scale is called BIOME
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SCALE
ECOSYSTEM
ECONOMIC
SYSTEM
SOCIAL
SYSTEM
Political
System
SMALL
LOCAL ECOSYSTEM
HOME ECONOMY
COMMUNITY
BAND
BIOME
MARKET ECONOMY
NATIONHOOD
TRIBE
GLOBAL
THE EARTH
GLOBAL SOCIETY
GLOBAL SOCIETY
NATION STATE
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HOME WORK
•Research about the GAIA Hypothesis
•Write an essay about this in one page
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•1.1.9-Construct and analyse quantitative models involving flows and storages in a system.
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What is a Model?
•A model is a simplified description to show the structure and working of a system.
•Models can be used to show the flows, storage and linkages within ecosystem.
•While they are unable to show much of the complexity of the real system, they help us to understand ecosystem function better
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•The width of arrows can vary in size; wider arrows are used to show larger flows.
•The size of boxes can also vary larger boxes are used to show larger storages
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•Shows nutrient flows and storages
•The biomass storage is larger in the woodland and the litter storage is larger in the forest
•Large output flow in the farming system because of the HARVESTED CROPS & LIVESTOCK
•Models that include quantitative descriptions of the system provide more meaningful information
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•1.1.10 Evaluate the strengths and limitations of models.
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EVALUATION OF MODELS
STRENGTHS
•Model allow scientist to predict and simplify complex systems
•They allow inputs to be changed and outcomes examined without having to wait a long time.
•Models allow results to be shown to other scientist and to the public and are easier to understand than detailed information about the whole system
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LIMITATION
•Different models may show different using the same data. For example models that predict the effect of climate change may give very different results
•Models are oversimplified they may become less accurate. for example there are many complex factors involved in atmospheric systems
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•Because many assumptions have to made about these complex factors climate models may not accurate
•Any model is only as good as the data that are used in them .In addition the data put into the model may not be reliable
•Models rely on the expertise of the people making them and this can lead to inaccuracies
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•Different people may interpret models in different ways and so come to different conclusion
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