Water and Carbon cycles as natural systems Flashcards
What are the main parts of a system?
INPUTS- when matter or energy is added to the system e.g. solar energy
OUTPUTS- when matter or energy leaves the system
STORES- where matter or energy builds up
FLOWS- when matter moves from one store to another
BOUNDARIES- the limits of the system
Example: In a drainage basin system, water enters as rain(input). The systems watershed is the boundary. Some water is stored in the soil and in vegetation (stores). Water travels from the drainage basin to the river and then down the river (flows). It leaves the system where the river meets the sea (output).
What’s the difference between open and closed systems?
OPEN SYSTEMS- Both energy and matter can enter and leave an open system- there are inputs and outputs for both.
Example: Drainage basins are open systems- energy from the sun enters and leaves the system. Water is input as precipitation(rain). and output as river discharge into the sea.
CLOSED SYSTEMS- Matter cant enter or leave a closed system- it can only cycle between stores. However energy can enter and leave a closed system- it can be input or output.
Example: The carbon cycle is a closed system- energy is input (sun by photosynthesis) and output (respiration), but the amount of carbon on earth stays the same because there are no inputs or outputs of matter.
What are the subsystems of the earth?
Cryosphere- the cryosphere includes all the parts of the Earth’s system where it’s cold enough for water to freeze e.g. glacial landscapes.
Lithosphere- The lithosphere is the outermost part of the earth. It includes the crust and the upper parts of the mantle.
Biosphere- The biosphere is part of the earth’s system where living things are found. It includes all the living parts of the earth e.g. plants, animals, birds, fungi, insects and bacteria.
Hydrosphere- The hydrosphere includes all the water in the earth, it may be in liquid form( lakes and rivers), solid form( ice), or gas form( water vapour). It can also be saline(salty) or fresh.
Atmosphere- The atmosphere is the layer of gas between the Earth’s surface and space, held in place by gravity.
What are positive and negative feedback?
Positive feedback:
-Positive feedback enhances or amplifies change, moving a system away from its equilibrium state and making it more unstable.
Negative feedback:
-Negative feedback counteracts the change, moving a system closer to its previous state and making it more stable.
What is an aquifer?
an underground layer of permeable rock which groundwater can be extracted from
