The carbon cycle

Question 1

Describe the effects of wildfires.

Answer 1

Release large amounts of carbon dioxide.
Turning the forest from a carbon sink into a carbon source.
Ash released can cause heath problems.

Question 2

How does volcanic activity contribute to the change in carbon levels?

Answer 2

Eruptions release carbon previously stored in the rock.

Question 3

Why has the demand for fossil fuels increased and what effect does this have?

Answer 3

Industrialisation of rapidly developing countries has led to an increase in the demand for fossil fuels.
Releasing carbon previously stored in organic materials.

Question 4

Explain how deforestation affects the natural carbon cycle.

Answer 4

Trees naturally die and decompose, releasing carbon which is absorbed by the newly growing vegetation; carbon neutral.
Deforestation releases large amounts of carbon which cannot be accounted for due to the change in land use.

Question 5

Main sources of carbon emissions in urban areas.

Answer 5

Transport, land use conversion and development.

Question 6

Explain how farming practices emit carbon.

Answer 6

Ploughing and harvesting, rearing livestock and using fertilisers.
Cattle produces methane.
Rice production accounts for 20% of global methane production.

Question 7

What is the carbon budget

Answer 7

Used to describe the amount of carbon stored and transferred within the carbon cycle

Question 8

Describe the impacts of the carbon cycle on land

Answer 8

• Carbon in the form of organic material provides important nutrients and structure to soil
• Valuable energy sources in wood and fossil fuels
• Essential for plant growth and food production

Question 9

Describe the impacts of the carbon cycle on the ocean

Answer 9

• Carbon converted into calcium carbonate is used by marine animals to make shells
• Vital to the presence of phytoplankton, basic food for marine animals, carbon is passed down the food chain

Question 10

Describe the impacts of the carbon cycle the atmosphere

Answer 10

• Carbon in the atmosphere warms the earth through the greenhouse effect
• Without this life would not survive

Question 11

How does vegetation in relation to carbon effect the climate

Answer 11

Vegetation takes in carbon dioxide and releases oxygen and water through photosynthesis.
Regions with dense vegetation experience higher rates of photosynthesis and respiration, increasing humidity and cloud cover.
Regions experiencing deforestation may become drier and less humid.

Question 12

Name some of the transfers of carbon

Answer 12

• Photosynthesis
• Respiration
• Decomposition
• Combustion
• Carbon sequestration
• Weathering

Question 13

Describe photosynthesis as a transfer of carbon

Answer 13

Carbon dioxide is absorbed from the air and soil and converted, using energy, to glucose and oxygen

Question 14

Describe respiration as a transfer of carbon

Answer 14

Glucose converted into energy for growth, repair and movement
Carbon dioxide returned to the air when exhaled

Question 15

Describe decomposition as a transfer of carbon

Answer 15

Organisms die and are consumed by decomposers, releasing carbon into the atmosphere

Question 16

Describe combustion as a transfer of carbon

Answer 16

When organic matter is burned in the presence of oxygen its converted into energy carbon dioxide and water
Releases carbon which would have been stored for millions of years

Question 17

Describe carbon sequestration as a transfer of carbon

Answer 17

‘Capture’ of carbon

The transfer of carbon from the atmosphere to plants, soil, rocks and oceans

Question 18

Describe weathering as a transfer of carbon

Answer 18

Carbon is absorbed by rainwater, forming middle acidic carbonic acid
Dissolves rock and carries carbon in solution to the oceans

Question 19

Name some of the stores of carbon

Answer 19

• Marine sediments and sedimentary rock
• Oceans
• Fossil fuels
• Soil organic matter
• Atmosphere

Question 20

Name the largest carbon store

Answer 20

Marine sediments and sedimentary rock (lithosphere)

Question 21

How does the ocean store carbon

Answer 21

Absorbs carbon directly from the air

Carries carbon in solution

Question 22

How is carbon released from soil

Answer 22

• Deforestation
• Land use change
• Soil erosion

Question 23

How is carbon stored in the atmosphere

Answer 23

Stored as carbon dioxide

Question 24

Name the fossil fuels which store carbon

Answer 24

Coal, oil and gas

Question 25

Name some characteristics of the carbon cycle seen in the rainforest

Answer 25

• Warm wet conditions ideal for plant growth, encourages photosynthesis
• Wood is a major carbon store
• Respiration of plants and animals releases C02
• Decomposers thrive in warm environments

Question 26

Name some impacts of human activity on the carbon cycle in the rainforest

Answer 26

• Burning trees releases stored carbon
• Photosynthesis ceases
• Rain washes ash into soil, increasing carbon content
• Plant and animal respiration drops