Water and carbon cycle 1 - Natural systems Flashcards
(37 cards)
What 5 things are systems made of
Stores, flows, boundaries, inputs and outputs
What are inputs
When matter or energy is added to the system
What are outputs
When matter or energy leaves the system
What are stores / components
Where matter or energy builds up
What are flows / transfers
Where matter or energy moves from one side to the other
What are boundaries
The limits of a system
What do systems have to be
Either open or closed
What’s an open system
Both energy and matter can enter and leave the system - there’s inputs and outputs
What’s an example of an open system
Drainage basins
Why are drainage basins open
Energy from the sun enters and leaves the system. Water is an input as precipitation and as an output as river discharge
What’s a closed system
Matter can’t enter or leave the system it can only cycle between stores. Energy can enter and leave - it can be an input and output
What is an example of a closed system
The carbon cycle
Why is the carbon cycle closed
Energy is an input from photosynthesis and an output as respiration, but the amount of carbon remains the same as there are no inputs or outputs of matter
What happens when the inputs and outputs are balanced
The system is in equilibrium
What does equilibrium mean?
Flows and processes happens but always in the same way so there is no overall change to the system
What does dynamic equilibrium mean
In reality there are small variations of inputs and outputs, they’re so small that the system still remains balanced as the outputs and inputs balance each other out
When do systems establish a new dynamic equilibrium
When there are long term changes to the balance of inputs and outputs can cause a system to change and establish a new dynamic equilibrium
What does this trigger
Positive or negative feedback
What does positive feedback do
Amplify the change in inputs or outputs
What does this mean
The system responds by increasing the effects of change, moving the system away from its previous state of dynamic equilibrium
What does negative feedback do
Counteracts the change in the inputs or outputs
What does this mean
The system responds by decreasing the effects of change, keeping the system closer to its previous state
What type of system is the earth
closed
Why is it a closed system
It has energy as an input from the sun and an output to space but matter isn’t an input or output to space
