Water and Carbon Cycles Flashcards Preview

AS AQA Physical Geography > Water and Carbon Cycles > Flashcards

Flashcards in Water and Carbon Cycles Deck (19)
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Open System:

- Energy and matter can enter and exit.

- EXAMPLE: Drainage Basin.


Closed System:

- Matter can enter but not exit.

- Energy can enter and exit.

- EXAMPLE: Carbon Cycle, Earth.


Positive Feedback:

- Amplifies change in inputs and outputs so the system increases effects of change and distances from previous state.


Negative Feedback:

- Counteracts change from inputs/outputs by decreasing effects of change; closer to previous state.


1) Cryosphere:

Includes all cold parts of the world; where water is cold enough to freeze.
- Glacial landscapes.

69% of Earth's freshwater is stored here.


2) Lithosphere:

Outermost part of Earth including the crust and upper mantle.


3) Biosphere:

Where living things are found.
- Plants, fungi, bacteria, animals, birds etc.


4) Hydrosphere:

Includes all water on the planet; liquid (water), solid (ice) or gas (water vapour).


5) Atmosphere:

Layer of gas between the Earth's surface and space.
- Held in place by gravity.

0.04% stored here as water vapour.


Outline the process of photosynthesis in the carbon cycle. (3 marks)

Photosynthesis is the process which takes in carbon dioxide from the atmosphere by plants and combines with water to produce oxygen and glucose, used in growth processes and energy by organisms. Because oxygen is produced, it is the by-product which maintains the CO2 balance.


Outline the role of weathering in the carbon cycle. (3 marks)

Weathering in the carbon cycle causes formations of weak carbonic acid, which is released from the sky and breaks down sedimentary rock such as limestone. The acid reacts with minerals in the rock and releases component ions, which are transported into the ocean where calcium bicarbonate is formed; then returned to stores in coral, plankton and shells. The carbon locked away is restored once the store is burned.


What is an artificial method of carbon sequestration?

Capturing carbon dioxide from coal fired power plants by piping it underground and storing in rock strata, porous enough to hold CO2.


What is a natural method of carbon sequestration?

Working with natural processes to create natural carbon sinks. The development of peat bogs will stop the vegetation decay. By creating new bogs or enhancing existing ones, carbon sequestration will naturally occur.


What is carbon sequestration?

Carbon from the atmosphere is captured and held in sedimentary rocks or as fossil fuels; formed after dead animals are compacted on the ocean floor. The carbon in these rocks is sequestered until burnt.


What is photosynthesis?

the transfer of carbon stored in the atmosphere to biomass, where plants and phytoplankton use chlorophyll to change carbon dioxide and water into oxygen and glucose for plant growth.


What is respiration?

the transfer of carbon from living organisms to the atmosphere as plants and animals break down glucose for energy and release CO2 and methane in the process.


What is combustion?

the transfer of carbon stored in living, dead or decomposed biomass to the atmosphere by burning. Wildfires case carbon flow.


What is decomposition?

the transfer of carbon from dead biomass to the atmosphere and soil. After death, bacteria and fungi break organisms down and CO2 and methane is released. Some carbon is transferred to the soil in the form of humus.


What is weathering?

the transfer of carbon from the atmosphere to the hydrosphere and biosphere. Atmospheric carbon reacts with water vapour to form acid rain, which falls onto rocks and dissolves them, resulting into molecules being washed into the sea. here they react with CO2 dissolved in the water to form calcium carbonate which is used by sea creatures to make shells.