Carbon Stores In Different Biomes

Question 1

Name the 6 main carbon reservoirs and how many gigatons of carbon they store

Answer 1

• Mantle (10,000,000)
• Crust (5,700,000)
• Oceans (38,000)
• Unburned fossil fuels (4,300)
• Vegetation and soils (3,800)
• Atmosphere (852)

Question 2

Where is carbon primarily stored in forests?

Answer 2

• Mainly biomass of trees

- Thick litter layers on forest floor

Question 3

How have forest landscapes been an important resource for human populations?

Answer 3

• Deforestation for timber

- Land clearance for agriculture

Question 4

How has forest clearing caused issues to carbon cycling?

Answer 4

Contributes carbon emissions to atmosphere through burning or decomposition of biomass

Question 5

How have impacts on carbon balance been variable in time and space?

Answer 5

• Clearing of rainforests led to increase in carbon emissions from topics
• North America, forest regrowth after Great Depression led to increase in carbon sequestration

Question 6

Which type of forest holds the largest carbon store?

Answer 6

• Coniferous due to being larger

- Tropical have greater biomass per unit area

Question 7

Give the 4 stores of carbon in a biome

Answer 7

• Green plants (20% of all carbon in Biosphere)
• Animals (Very small)
• Litter (Relatively small)
• Soil (Humus is rich in carbon)

Question 8

How does light affect plant growth and carbon storage in tropical rainforests?

Answer 8

• Sun rays are concentrated at this latitude, little seasonal variation
• All year growth and carbon sequestration

Question 9

How do temperatures affect plant growth and carbon storage in tropical rainforests?

Answer 9

• High average temps 25°C to 30°C, small seasonal variations

Question 10

How does precipitation affect plant growth and carbon storage in tropical rainforests?

Answer 10

• Very heavy convectional rainfall (2000-3000mm per year)

- No dry season

Question 11

What do physical factors of tropical rainforests result in?

Answer 11

• High rainfall = Optimum conditions for plant growth and biomass carbon storage
• Competition for light and water created 5 tier structure
• Carbon stores high
• 550 gigatons of carbon stored in tropical rainforests

Question 12

Where are grasslands found?

Answer 12

• Between 30 and 50 degrees north of equator
• Leeward side of mountains
• Periphery of deserts

Question 13

Name 3 temperate grasslands

Answer 13

• North American Prairies
• Eurasian Steppes
• South African Veld

Question 14

How does light affect plant growth and carbon storage in temperate grasslands?

Answer 14

• Sun’s rays concentrated during summer at latitudes, but weaker in winter
• Pronounced variations in plant growth and biomass storage

Question 15

How do temperatures affect plant growth and carbon storage in temperate grasslands?

Answer 15

• 0 to 22 degrees

- Encourages large seasonal changes in stored biomass carbon

Question 16

How does precipitation affect plant growth and carbon storage in temperate grasslands?

Answer 16

• Low annual rainfall (500mm or less)

- Limits plant growth and variations in seasonal biomass carbon

Question 17

Name the two common grasses found in temperate grasslands

Answer 17

• Turf grasses (Humid parts of biome)

- Bunch grasses (Drier parts of biome)

Question 18

Outline earthworms in temperate grasslands

Answer 18

• 500 per metre²
• Consume organic matter, key role in carbon cycling
• 10 years, entire top layer of soil passed through guts of earthworms

Question 19

What are the carbon stores and flows in temperate grasslands?

Answer 19

• Store 185 gigatonnes of carbon
• Humid conditions ensure rapid decomposition of dead grass, releases CO²
• Winter, grasses die and photosynthesis ceases

Question 20

Give 3 effects of deforestation on carbon

Answer 20

• Removes carbon biomass store
• Reduces organic input to soil and loss of carbon storage capacity
• Above ground biomass increased in recent years due to sequestering of increased CO² concentration

Question 21

What is afforestation?

Answer 21

• Planting trees in deforested places

- Trees act as carbon sinks