1.2 - Sytems And Models

Question 1

What does the term systems approach mean

Answer 1

used to describe a method of simplifying and understanding a complicated set of interactions

Question 2

What could systems and interactions be

Answer 2

Systems, and the interactions they contain, may be environmental or ecological (e.g. the water cycle or predator-prey relationships), social (e.g. how we live and work) or economic (e.g. financial transactions or business deals)

Question 3

What does the interactions within a system produce

Answer 3

The interactions within a system, when looked at as a whole, produce the emergent properties of the system
For example, in an ecosystem, all the different ecological interactions occurring within it shape how that ecosystem looks and behaves - if the interactions change for some reason (e.g. a new predator is introduced), then the emergent properties of the ecosystem will change too

Question 4

What are the 2 main ways of studying systems

Answer 4

A reductionist approach involves dividing a system into its constituent parts and studying each of these separately - this can be used to study specific interactions in great detail but doesn’t give the overall picture of what is occurring within the system as a whole

A holistic approach involves looking at all processes and interactions occurring within the system together, in order to study the system as a whole

Question 5

What are some examples of interactions between factors in the case of sustainability or sustainable development

Answer 5

These include environmental, social and economic factors (sometimes referred to as the three pillars of sustainability

A systems approach is required in order to understand how these different factors combine and interact with one another, as well as how they all work together as a whole (the holistic approach)

Question 6

What is a system comprised of

Answer 6

Storages and flows

Question 7

What does a flow provide

Answer 7

The flows provide inputs and outputs of energy and matter

Question 8

What are the 2 process of a flow

Answer 8

• transfers (change in location)
• transformations (a change in the chemical nature)

Question 9

Define transfer

Answer 9

Transfers are the movement of matter or energy from one component of the system to another, without any change in form or quality

• For example, water flowing from a river to a lake is a transfer

Question 10

Define transformation

Answer 10

Transformations, on the other hand, involve a change in the form or quality of matter or energy as it moves through the system

• For example, when sunlight is absorbed by plants, it is transformed into chemical energy through the process of photosynthesis

Question 11

How are transfers and transformations represented in a systems diagram

Answer 11

Transfers and transformations are often represented in systems diagrams by arrows that connect the different components of the system

• Arrows that represent transfers are usually labeled with the quantity of matter or energy being transferred (e.g., kg of carbon, kJ of energy), while arrows that represent transformations may include additional information about the process involved (e.g., photosynthesis, respiration)

Question 12

What does the proccesses of systems diagram show

Answer 12

By understanding these processes, it is possible to identify opportunities to improve the efficiency or sustainability of the system

Question 13

Do transfers and transformations occur at the same scale

Answer 13

Transfers and transformations can occur at different scales within a system, from the molecular level to the global level

• For example, at the molecular level, nutrients are transferred between individual organisms, while at the global level, energy is transferred between different biomes

Question 14

How are storages represented of a systems diagram

Answer 14

Storages are commonly drawn as boxes

Question 15

How are flows represented on a systems diagram,

Answer 15

Flows are commonly drawn as arrows

Question 16

What are the three main types of systems

Answer 16

Open systems
Closed systems
Isolated systems

Question 17

How do you determine the type of system

Answer 17

The category that a system falls into depends on how energy and matter flow between the system and the surrounding environment

Question 18

What energy and matter exchange categorises a open system

Answer 18

Both energy and matter are exchanged between the system and it surrounding

Question 19

Are open systems inorganic or organic

Answer 19

Open systems are usually organic (living) systems that interact with their surroundings (the environment) by taking in energy and new matter (often in the form of biomass), and by also expelling energy and matter (e.g. through waste products or by organisms leaving a system)

Question 20

What is an example of a open system

Answer 20

• your body
• ecosystem

Question 21

What energy and matter exchange categorises a closed system

Answer 21

Energy, but not matter, is exchanged between the system and its surroundings

Question 22

Are closed systems organic or inorganic

Answer 22

Closed systems are usually inorganic (non-living), although this is not always the case
The International Space Station (ISS) could perhaps be seen as a closed system
It is a self-contained environment that must maintain a balance of resources, including air, water, and food, as well as waste management, energy production, and temperature control
The ISS cannot exchange matter with its surroundings

Question 23

What type of system could the earth be classified as

Answer 23

The Earth (and the atmosphere surrounding it) could be viewed as a closed system
The main input of energy occurs via solar radiation
The main output of energy occurs via heat (re-radiation of infrared waves from the Earth’s surface)
Matter is recycled completely within the system
Although, technically, very small amounts of matter enter and leave the system (in the form of meteorites or spaceships and satellites), these are considered negligible
Artificial and experimental ecological closed systems can also exist - for example, sealed terrariums, containing just the right balance of water and living organisms (such as mosses, ferns, bacteria, fungi or invertebrates) can sometimes survive for many years as totally closed systems, if light and heat energy is allowed to be exchanged across the glass boundary

Question 24

What is the energy and matter exchange in an isolated system

Answer 24

Neither energy nor matter is exchanged between the system and its surroundings

Question 25

What is an example of an isolated system

Answer 25

Isolated systems do not exist naturally - they are more of a theoretical concept (although the entire Universe could be considered to be an isolated system)

Question 26

What is a model

Answer 26

A model is a simplified version of reality

Question 27

What is a model used to represent

Answer 27

model is often used to represent a system
The model can then be analysed or tested to learn more about how the system works and to predict how the system might respond to change
For example, weather models are used to predict how our weather systems change over time, allowing us to create weather forecasts

Question 28

What are the 6 strengths of a model

Answer 28

1. Models simplify complex systems
2. Models allow predictions to be made about how systems will react in response to change
3. System inputs can be changed to observe effects and outputs, without the need to wait for real-life events to occur
4. Models are easier to understand than the real system
5. Results from models can be shared between scientists, engineers, companies and communicated to the public
6. Results from models can warn us about future environmental issues and how to avoid them or minimise their impact

Question 29

What are the 6 limitations of a model

Answer 29

1. Models can be oversimplified and inaccurate
2. Results from models depend on the quality of the data inputs going into them
3. Results from models become more uncertain the further they predict into the future
4. Different models can show vastly different outputs even if they are given the same data inputs
5. Results from models can be interpreted by different people in different ways
6. Environmental systems are often incredibly complex, with many interacting factors - it is impossible to take all possible variables into account