1.1.1 Natural systems

• A system is an assemblage of interrelated parts that work together. They are a series of stores or components and have flows between them
• A system has a structure that lies within a boundary. It has 3 different properties - elements, attributes and relationships
• Systems work by having inputs and outputs, an open system allows both mass and energy to flow across a boundary whereas a closed system only lets energy flow across the boundary
• An isolated system is where there is no interaction between the system and its surroundings, it's artificial and theoretical
• Dynamic equalibirium is the balance between the inputs and outputs. The stores stay the same
• If one element changes in a dynamic equilibrium then it is upset this is called feedback
• Positive feedback, enhances or amplifies an effect by having an influence on the loop
• Negative feedback, dampens or reduces an effect by having an influence on the system
• What are some examples of closed systems?


  The water system - there is a foxed amount of water on the earth and in the atmosphere, water spends time in the ocean, the air, on the surface and in the groundwater. It exists as a solid, liquid and gas and its form is interchangeable