1. Environmental Systems
Topic - 1 Systems and Models
Statements 1.A – 1.G

2. What is Environmental Systems About?
In this course we will be studying and analyzing the environment as a set of complex systems.
We won’t look at them separately as a biologist, geologist, or earth scientist would - but as all three professions combined.

3. So what is a system?
Systems are sets of entities that function as a whole.
A group of parts connected together in an organized way to make a more complex entity.

4. Examples of Systems

5. The System that we will study most….
The Ecosystem - a community of organisms in its abiotic environment, together with the relationships amongst these components.

6. Every system has a boundary
Outside of that boundary lies the system’s environment.
Environment: everything outside of a system that can influence the system or can be influenced by the system.
-Therefore different systems can be linked.

7. Diagraming Systems All systems have: Represented by:
STORAGES or stocks of matter and energy.
FLOWS into, through, and out of the system
INPUTS
OUTPUTS
BOUNDARIES
PROCESSES which transfer and transform energy or matter
A box
Size of box represents amount.
Arrows
Arrows in
Arrows out
Lines
Arrows between storages

8. Stock size is dependent on both the input and the output.
Tree farm planting = cutting
Stock size is dependent on both the input and the output.
Use of Fossil fuels
Pollution of lakes with pesticides

9. Transfers within a system
Transfer - when matter or energy is moved from one location to another.
Examples?
Come up with at least 5 transfers and transformations with those around you.

10. Transformations within a System
Transformation - interaction within a system that forms a new end product or involves a change in state.
Examples?

11. Open Systems
A type of system that exchanges matter and energy across its boundary with its environment.
Therefore, these systems exchange factors with other systems around them.
Almost all systems are open systems.

12. Diagram of an Open System

13. Closed System
A system that exchanges energy with its environment but not matter.
Closed systems are not found in nature.
But globally, the cycles of matter can be thought of as closed systems
Ex:
How could you diagram a closed system?

14. Isolated Systems
A System that exchanges neither matter nor energy with its environment.
This cannot exist.
Possible exception???
Students stand up and pair up. Student 1 – define Open; Student 2 – example Open
Student 2 – define Closed; Student 1 – example Closed
Student 1 – define Isolated; Student 2 – example Isolated

15. The First Law of Thermodynamics
First Law - Energy may not be created or destroyed, but may change from one form to another.
AKA - The Law of Conservation of Energy
What does this mean?
Examples?

16. The Second Law of Thermodynamics
What is needed for any system to be sustaining?
What happens to energy in a system?
This is called the Second Law of Thermodynamics – Entropy or disorder in a system increases over time.
Why?
Eventually, all energy is emitted back into the environment as unusable heat, but it is NOT destroyed.
Example?

17. Second Law of Thermodynamics
Stand up, pair up with someone new in area.
Describe one thing you understand about the Laws of Therm to each other.
Ask each other a question that you would like explained about the Laws.
Because energy is decreasing over time or through a system, what do all systems need to have?

18. While energy is continuously flowing through systems….

19. matter tends to circulate around inside of it.