Systems

Environmental Systems and

Societies

Interrelationships among climate, geology, soil,

vegetation, and animals. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 1

INDEX • Type of System

• Components of a system

• Thermodynamics nutrient cycles

• Laws of Thermodynamics

• Transfer vs. transformation

• Laws of Thermodynamics

• Equilibria-Steady-State-Static

• Feedback Mechnasim

ESS/GURU/CHAPTER1 SYSTEMS & MODELS 2

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.


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.


TYPES OF SYSTEM

1. OPEN SYSTEM

2. CLOSED SYSTEM

3. ISOLATED SYSTEM


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. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 7

2. CLOSED SYSTEM: a system in which energy

is exchanged across boundaries of the system, but

matter is not. Example-Aquarium & Terrarium


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


3. ISOLATED SYSTEM: a system in which

neither energy nor matter is exchanged with

its envioronemt.Do not exist naturally

NO SUCH SYSTEM EXISTS!!!


CLOSED SYSTEM CLOSED SYSTEM

CLOSED SYSTEM

OPEN SYSTEM

OPEN SYSTEM


Components of a system:

1. Inputs such as energy or

matter.

Calories

Protein


2. Flows of matter or energy within the

systems at certain rates.

Calories

Protein

Calories

Protein


3.Outputs of certain forms of matter or

energy that flow out of the system into

sinks in the environment.

Calories

Protein

WasteHeat

WasteMatt

er


4. Storage areas in which energy or matter can

accumulate for various lengths of time before

being released.

Calories

Protein


RECAP

• What is open system? Example

• What is closed system? Example

• What is Isolated system? Example

• Components of a system


Inputs and Outputs


energy input from sun

PHOTOSYNTHESIS (plants, other producers)

energy output (mainly heat)

nutrient cycling

RESPIRATION (hetero & autos, decomposers)


Thermodynamics nutrient

cycles


Laws of Thermodynamics

• 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


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.


TRANSFERS OF ENERGY

TRANSFORMATTION OF ENERGY


Cycling of Chemical Elements

TRANSFERS: normally flow

through a system and involve a

change in location.

TRANSFORMATIONS: lead to

an interaction within a system in

the formation of a new end

product, or involve a change of

state. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 31

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

• Energy examples ESS/GURU/CHAPTER1 SYSTEMS & MODELS 32

TRANSFERS OF ENERG


TRANSFERS OF ENERGY


ENERGY TRANSFORMATIONS


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 .


Distinguish flows and storage

• Flows are input and output -

• exmple….input food -- output wastes energy

• Storage -- usually a transformation into a form of matter/energy that can be used later……


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?


• Two laws

• First Law of Thermodynamics

• Second Law of Thermodynamics


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.


First Law of Thermodynamics

ENERGY 2

PROCESS

ENERGY 1 (WORK)

ENERGY 3


Photosynthesis: an example of the First Law

of Thermodynamics: Energy Transformation


Photosynthesis and the First Law of Thermodynamics

Heat

Energy

Light Energy

Chemical

Energy

Photosynthesis


Thermal equilibrium = inputs equal outputs over a long period of time. ESS/GURU/CHAPTER1 SYSTEMS & MODELS 48

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


Answer this………………..


Using the first law of thermodynamics explain why the

energy

pyramid is always pyramid shaped (bottom bigger than

top) ESS/GURU/CHAPTER1 SYSTEMS & MODELS 51

WORLDS TALLEST FLOWER


titan arum


• The titan arum or Amorphophallus titanum s

a flowering plant with the largest unbranched

inflorescence in the world.

• The titan arum's inflorescence can reach over

3 metres (10 ft) in circumference.

• The leaf structure can reach up to 6 metres

(20 ft) tall and 5 metres (16 ft) across

• The corm is the largest known, weighing

around 50 kilograms (110


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 from to another 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


• 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:


What results from the second law of Thermodynamics?


Second Law of Thermodynamics


•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)


Only 25% of chemical “E” stored in gasoline is transformed in to motion of the car and 75% is

lost as heat!!


RECAP

• What is a SYSTEM?

• Types of system

• What is open system

• Closed system

• Isolated system

• What is thermo dynamics?

• What is First law of thermodynamics?

• What is second law of thermodynamics?

• What is transfer of energy?

• What is transformation of energy?

• Tallest flower


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


Without adding energy to a system, the system will break down .


Primary Producers and the 2nd law of Thermodynamics

(Output)

(Output)

(Output)


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?


The Ecosystem and the 2nd law of Thermodynamics

Heat

Heat

Heat

Heat

Heat


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


RECAP

• What is First Law of Thermodynamics

• What is Second Law of

Thermodynamics?

• What is EQUILIBRIUM?

• Three types of equilibrium


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.


3 TYPES

1. STEADY –STATE EQUILIBRIUM

2. STATIC EQUILIBRIUM

3. STABLE & UNSTABLE EQUILIBRIUM


STEADY –STATE EQUILIBRIUM EXAMPLE

If these birth & death rates are equal there is no net change

In population size

birth

death


WHERE YOU CAN SEE STEADY –STATE

EQUILIBRIUM IN ECOSYSTEM

QUESTION


Food chain & Food web are the example of Steady –State Equilibrium


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


Rate of water entering = Rate

of water leaving

Hence the level of water is

constant


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


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.


QUESTION

WHERE YOU CAN SEE STATIC

EQUILIBRIUM IN ECOSYSTEM


• Most non living system are in Static

Equilibrium


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


FOREST FIRE -DISTURBANCE

AFTER DISTURBANCE


RECAP

• What is First Law of Thermodynamics

• What is Second Law of

Thermodynamics?

• What is EQUILIBRIUM?

• Three types of equilibrium


Rafflesia

Found in the Indonesian rain forest


RECAP

1. What is Equilibrium

2. STEADY –STATE EQUILIBRIUM

3. STATIC EQUILIBRIUM

4. STABLE & UNSTABLE EQUILIBRIUM


What is FEEDBACK?

• Systems are continually affected by

information from outside & inside the system

is called as FEEDBACK

• Feedbacks can be positive or negative


The sense of cold is the information, putting on clothes or

heating up is the reaction

cold

clothes

heating up


Respond Positively in the class

Showing interest

Teacher is successful

POSTIVE FEEDBACK


NEGATIVE FEEDBACK

Respond negatively in the class

Showing distraction

Methodology is not appropriate


What is feedback loop?

• Natural system act in exactly the same way.

• The information starts a reaction which in turn

input more information which may starts

another reaction.

• This is feedback loop


Positive and Negative

Feedback


• The way that living systems and non

living systems self-regulate or maintain

homeostasis (the maintenance of a steady

state in an organism, ecosystem or

biosphere) is through feedback systems is

called as FEEDBACK SYSTEM

What is FEEDBACK SYSTEM?


Walking in hot sun, temperature rises

Body will lose heat

ONE ACTION IS INCREASING

ONE ACTION IS DECREASING

Negative feedback systems


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.


Example of Negative Feedback

• Predator/prey relationships


• 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.


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.


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


ANSWER THIS

• IDENTIFY THIS BIRD


SARUS CRANE

at a height of up to 1.8 m (5.9 ft)


SEPTEMBER FORMATIVE &

SUMMATIVE

• Formative- Worksheet

• Marks-30

• Summative –Test

• Date-19.09.2012

• Marks-45

• Times:1 hour ESS/GURU/CHAPTER1 SYSTEMS & MODELS 114

POSTIVE FEEDBACK


Poor standards of education

Absence of family planning

Positive feedback poverty


Positive feedback • A runaway cycle – often called vicious cycles

• A change in a certain direction provides output that

further increases that change

• 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


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.


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


Most systems change by a

combination of positive and

negative feedback processes


Which of the populations show positive feedback? Which of the populations show negative feedback?

I-POSTIVE FEEDBACK

II-NEGATIVE

III-NEGATIVE

IV-POSTIVE


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....


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)


Equilibrium generally maintained by

negative feedback – inputs should equal

outputs


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 ESS/GURU/CHAPTER1 SYSTEMS & MODELS 129

High Throughput

System Model


High-quality

energy

Matter

System

Throughputs

Output

(intro environment)

Unsustainable

high-waste economy

Low-quality heat

energy

Waste

matter and

pollution

Inputs

(from environment)


Low Throughput

System Model


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)


Easter Island

What are the statues and where are the trees? A caseStudy in unsustainable growth practices.


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… ESS/GURU/CHAPTER1 SYSTEMS & MODELS 136

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


http://www.nhc.noaa.gov/archive/2008/FAY_graphics.shtml

http://www.nhc.noaa.gov/archive/2008/FAY_graphics.shtml

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


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

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Other systems examples


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 ESS/GURU/CHAPTER1 SYSTEMS & MODELS 141

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 ESS/GURU/CHAPTER1 SYSTEMS & MODELS 142

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


Systems

Education

Transcript of Systems