Natural Systems Part 1 Flashcards
Define system
A set of interrelated components working together towards some kind of process.
Parts of System
. Stores / Components
. Flows / Transfers
. Boundaries
. Inputs
. Outputs
Define Flows / Transfers
When matter or energy moves from one store to another.
Define Stores / Components
where matter or energy is stored and builds up.
Define Boundaries
the limits of the system
Define Inputs
where matter or energy is added to a system (e.g. solar energy)
Define Outputs
when matter or energy leaves the system
Name three types of systems
. Open system
. Closed system
. Isolated system
Define open system
. Both energy and matter can leave an open system — there are inputs and outputs
Define closed system
. Matter can’t enter or leave a closed system — it can only cycle between stores
. Energy can enter and leave a closed system— it can be an input or output
Define isolated system
. These have no interactions with anything outside the system boundary
. There is no input of matter or energy into the system
Examples of open system
. Drainage basin system
Examples of closed system
. Earth
. Carbon cycle
. Global Hydrological System ( in simple terms it is the water cycle)
Examples of isolated system
. No examples in nature
. Controlled lab experiments are isolated systems
Define Dynamic Equilibrium
. A system is in dynamic equilibrium if the inputs and outputs of the system are balanced on average
. Stores stay the same
. Flows and processes continue to happen
What happens if one of the elements of the system changes? e.g. change in input without any corresponding change in output
. Dynamic Equilibrium is upset
. This is called feedback
Name two types of feedback
. Positive feedback
. Negative feedback
Explain positive feedback
.where the effects of an action are amplified or multiplied by subsequent knock-on or secondary effects
. The system increases the effects of the change, moving the system even further from its previous state
Explain negative feedback
.where the effects of an action are nullified by its subsequent knock-on effects
. the system decreases the effects of the change, keeping the system closer to its previous state
Is there a difference between dynamic equilibrium and equilibrium?
Yes, equilibrium is when the inputs and outputs are perfectly balanced, which flows and processes continuing to happen in the same way at all times
Dynamic equilibrium has lots of small variations in the inputs and outputs of the system (e.g. amount of precipitation entering a drainage basin system constantly varies.) The variations are small, so the inputs and outputs remain balanced on average.
Example of positive and negative feedback
. Refer to CGP book
