Systems concepts on the coast
- Created by: rchapman99
- Created on: 24-06-17 20:36
View mindmap
- Systems concepts on the coast
- System
- A process or collection of processes that transforms inputs into outputs.
- 3 properties
- Elements - parts that make up a system.
- Attributes - characteristics of the elements that may be perceived and measured.
- Relationships - associations that occur between elements and attributes.
- 3 properties
- Common characteristics
- Abstractions of reality.
- Behaviour: inputs, outputs, energy.
- Functional as well as structural relationships.
- Closed system - transfer of energy into and beyond the system but no transfer of matter.
- Open system - both energy and matter transfer freely into and out of the system.
- Isolated system - no interactions with anything outside the system boundary; no input or energy of matter.
- Inputs: energy (waves, wind, tides) and matter (sediment, fluvial processes of erosion, glaciation, cliff/coastline erosion & sub-aerial erosion.
- Stores/processes: beaches, sand dunes, salt marshes, cliff and wave-cut platforms.
- Components: erosional and depositional coastal landforms.
- Outputs: dissipation of wave energy, accumulation of sediment above tidal limit, sediment removed beyond cells.
- A process or collection of processes that transforms inputs into outputs.
- Feedback
- Feedback mechanism - a process that use the conditions of one component to regulate the function of the other.
- Two types of feedback
- Positive feedback - feedback where there is a progressively greater change from the original condition of the system.
- E.g. trampling on sand dunes - causes erosion of sand and damage to vegetation - blowout.
- Negative feedback - feedback keeps a system in its original condition.
- E.g. fishtail groynes - change destructive waves into constructive waves - wave length increases and wave height decreases - more deposition.
- Positive feedback - feedback where there is a progressively greater change from the original condition of the system.
- Equilibrium
- Coasts are dynamic.
- The morphology of the coast responds to changes in energy because it aims to exist in a state of equilibrium with the reigning processes.
- Dynamic equilibrium - the balanced state of a system when its inputs and outputs are equal.
- Depends on 1. supply of sand 2. wave energy 3. sea level change 4. location.
- Steady state equilibrium - where variations in energy and the morphological response in a situation do not deviate too far from the long-term average.
- E.g. along a coast with consistent wave energy conditions, there may be a steep gradient at some times of the year and shallower at others but the annual gradient remains fairly similar.
- Meta-stable equilibrium - where an environment switches from two or more states of equilibrium and the switch stimulates by some sort of trigger.
- E.g. the action of high energy events can rapidly switch a coastal system from one state to another.
- System
Similar Geography resources:
Teacher recommended
Teacher recommended
Teacher recommended
Comments
No comments have yet been made