Topic 1.2 - Systems

Systems

Sets of interacting or interdependent components organized to create a functional whole.

Systems approach

A holistic way of visualizing complex interactions applicable to ecological or societal situations.

Storages

Represented as rectangular boxes in system diagrams, indicating the storage of energy or matter.

Flows

Processes in systems that provide inputs and outputs of energy and matter, represented as arrows in diagrams.

Transfers

A type of flow involving a change in location of energy or matter.

Transformations

A type of flow involving a change in chemical nature, state, or energy.

Open system

A system that exchanges both energy and matter across its boundary; examples include forests.

Closed system

A system that exchanges only energy across its boundary; examples include the mesocosms we made.

Isolated System

A system that exchanges neither energy nor matter across its boundary and is purely hypothetical; examples include an adiabatic (perfectly insulated) drinks flask (impossible).

Gaia hypothesis

A model proposing that Earth is a single integrated system, explaining interrelations of atmospheric composition and temperatures.

Scale of systems

Systems can range from small local ecosystems to large global systems like the Gaia hypothesis.

Negative feedback loops

Processes that inhibit or reverse operations to reduce change, stabilizing the system.

Stable equilibrium

A condition where a system tends to return to its previous state after disturbance.

Positive feedback loops

Processes that amplify disturbances, destabilizing the system and driving it away from equilibrium.

Tipping point

The minimum change that causes destabilization within a system, leading to a new equilibrium.

Regime shifts

Large overall changes resulting from small alterations in one component of a system.

Model

A simplified representation of reality used to understand and predict system behavior.

Simplification of a model

Involves higher approximation and loses accuracy, affecting predictive capabilities.

Emergent properties

Characteristics that arise from interactions between system components, not present in isolated components.

Resilience

The ability of a system to avoid tipping points and maintain stability despite disturbances.

Diversity and storages

Factors that contribute to a system's resilience and affect its response speed to changes.

Human impact on resilience

Reduction of storages and diversity by human activities, such as deforestation, affecting system stability.

Biosphere

The part of the earth where living organisms exist

Atmosphere

The layer of air surrounding the Earth’s surface

Hydrosphere

The layer of water on and near the Earth’s surface (this includes the frozen water)

Cryosphere

The layer consisting of frozen water, including frozen ground  

Geosphere

The layer that includes all the rocks and minerals from the centre of the Earth to the non-living parts of the soil

Anthroposphere

The total human presence throughout the Earth system, including our culture, technology, built environment, and associated activities