System interactions and processes Flashcards
(14 cards)
dynamic equilibrium is
the balance between the inputs and outputs of a system
in dynamic equilibrium, all the stores stay
the same
in dynamic equilibrium, if one of the elements changes without any corresponding change, then
the equilibrium is upset
when the equilibrium is upset, we call this
feedback
two types of feedback are
positive and negative feedback
positive feedback is when
the effects of an action are amplified by subsequent knock-on or secondary effects
negative feedback is when
the effects of an action are nullified by its subsequent knock-on effects
an example of negative feedback is
the combustion of fossil fuels leads to increased vegetation growth so the co2 concentration int he atmosphere decreases as plants store the carbon in photosynthesis
an example positive feedback is
an increase in carbon dioxide which raises temperatures, meaning permafrost melts, releasing more co2 and so increasing temperatures further
the earth as a whole can be considered a ……..system
closed system
the concept of spaceship earth is
about how earth as a closed system means we have limited resources but we ca use energy from the sun (or derived from it) as an infinite source, though matter is limited
the four major subsystems of earth are
- atmosphere
- lithosphere
- hydrosphere
- biosphere
each subsystem of earth can be considered as ………systems
open systems
each subsystem of earth forms part of a chain called
a cascading system
