Carbon cycle EQ3

Question 1

human population growth and an increase in economic development have changed the ways people use land

Answer 1

• greater demand for resources eg food
• economic needs change - improving living standards

Question 2

positives of land use change

Answer 2

• absorbs carbon into its biomass and soils
• sustain habitat quality and biodiversity
• regulates water cycle locally and globally

Question 3

negatives of land use change

Answer 3

• deforestation emits carbon into atmosphere
• deforestation can lead to droughts and desertification
• deforestation can lead to more intense flooding

Question 4

the amazon

Answer 4

• 11000 sq km of rainforest destroyed from 2019-2022
• 3 million species and 1 million indigenous people
• brazils president encouraged agriculture and mining activities there

Question 5

deforestation impact on water cycle

Answer 5

• infiltration decreased
• runoff and erosion increased
• flood peaks higher and lag time shorter
• flooding

Question 6

deforestation impact on soil health

Answer 6

• CO2 released from decaying woody material
• biomass is lost

Question 7

deforestation impact on the atmosphere

Answer 7

• oxygen content reduced and transpiration rates lower
• reduced shading leads to more direct sunlight reaching the ground

Question 8

deforestation impact on the biosphere

Answer 8

• less absorbtion of CO2 means reduced carbon store
• biomass is lost from reduced photosynthesis

Question 9

benefits of natural grasslands

Answer 9

• acts as a carbon sink - absorbing CO2 and releasing O2 all year round (a ‘lung effect’)
• acts as a terrestral carbon store

Question 10

disadvantages of converting grasslands to grow biofuel crops

Answer 10

• initial removal of grass releases CO2 from soils
• anual ploughing releases CO2 from soil bacteria
• biofuel crops need carbon-based nitrogen fertiliser and chemical pesticides, so they produce a net increase in CO2 emissions
• the ‘lung effect’ is reduced

Question 11

BBC news: Carbon capture projects will support 2000 jobs

Answer 11

£22bn funding for ‘carbon capture clusters’ on Teesside and Merseyside over nect 25 years

Question 12

ecosystem

Answer 12

a biological community of interacting organisms and their physical environment eg a forest or a desert

Question 13

ecosystem services

Answer 13

a holistic term to describe the services that ecosystems provide such as soil formation, food provision, climate regulation and recreation facilities

Question 14

provisioning services definition, examples, coral reefs

Answer 14

d:products obtained from ecosystems

e:food, fuel, drugs, transportation, national defence

c:millions of people depends on reefs for the fishing industry

Question 15

regulating services definition, examples, coral reefs

Answer 15

d:benefits obtained from the regulation of ecosystem processes

e:regulating air quality, pollination, flood prevention, control of pests, climate regulation

c: reduce waver energy by 95%, protecting coastlines from erosion

Question 16

cultural services definition, examples, coral reefs

Answer 16

d: non-material benefits obtained from ecosystems

e: spiritual well-being, science, educational, recreation, heritage

c: provide evidence and education of where life began

Question 17

supporting services definition, examples, coral reefs

Answer 17

d: services necessary for the production of all other ecosystem services

e: soil formation, photosynthesis, water cycling, biological diversity, primary productivity

c: shelter 25% of marine species

Question 18

ocean acidification

Answer 18

the decrease in the pH of the earths oceans caused by the uptake of carbon dioxide from the atmosphere

Question 19

ecosystem resilience

Answer 19

the level of disturbance that ecosystems can cope with while keeping their origional state

Question 20

Deforestation Trends (2000-2012)

Answer 20

Global forest loss of 2.3 million km², particularly in tropical regions (e.g., Bolivia, Indonesia, Angola). Boreal forests also lost due to fires and forestry.

Question 21

Carbon Storage & Climate Impact:

Answer 21

Tropical rainforests store 32% of global forest carbon. Deforestation disrupts the carbon cycle, reducing carbon sequestration and increasing atmospheric CO₂.

Question 22

Water Cycle Links to forest loss

Answer 22

Trees regulate water through interception, evapotranspiration, and absorption. Deforestation reduces these processes, affecting water supplies.

Question 23

Key Concerns:

Human Drivers & Impacts

Answer 23

Forest loss has been a major issue since the 1970s. Despite slowing in some areas (e.g., Brazil), deforestation continues, driven by agriculture (soya, palm oil), plantations, and hydroelectric projects.

Question 24

Fires & Feedback Loops

Human Drivers & Impacts

Answer 24

Deforestation dries out soils, increasing susceptibility to fires, which release aerosols, degrade air quality, and worsen respiratory issues (e.g., Amazonia drought, 2005).

Question 25

Soil Degradation | Human Drivers & Impacts

Answer 25

Loss of vegetation leads to soil erosion, threatening food security.

Question 26

Kuznets Curve Theory | Economic & Policy Influences

Answer 26

Environmental degradation initially rises with economic development but later improves as policies and technology advance. Brazil’s forest policies show potential for a ‘turning point.’

Question 27

Global Trends | Economic & Policy Influences

Answer 27

Indonesia had the highest forest loss (2000-2012). Developed nations show afforestation efforts (e.g., boreal forest expansion post-wildfires). Russia saw the largest net forest loss (365,015 km²).

Question 28

Rising Temperatures & Ice Loss | changes in the Arctic water cycle

Answer 28

* The Arctic is experiencing the fastest global temperature increase, especially in winter. * Higher temperatures lead to more evaporation, humidity, and permafrost thawing (with increased river discharges). * Arctic sea ice is shrinking rapidly and could be ice-free by 2037

Question 29

Hydrological Changes & River Systems | changes in the Arctic water cycle

Answer 29

* Increased snow and glacial melt (e.g., Greenland) affect river runoff, leading to more floods. * Arctic lakes freeze later, and river discharges peak earlier due to earlier spring thaws. * Eurasian river discharges are increasing due to moisture shifts toward the pole

Question 30

Environmental & Human Impacts | changes in the Arctic water cycle

Answer 30

* Permafrost thaw causes infrastructure collapse, threatening Arctic communities. * Wildlife and ecosystems shift, leading to food insecurity for Indigenous peoples. * Extreme weather, floods, and droughts impact water quality and availability

Question 31

Uncertainty in Future Projections | changes in the Arctic water cycle

Answer 31

* Climate models lack complete data for long-term Arctic feedback effects. * More monitoring sites are needed to improve predictions of Arctic changes

Question 32

uncertain futures - natural factors

Answer 32

- oceans take decades to respond to greenhouse gasses - global total of forests is falling eg tropics - oceans and forests act as carbon sinks and store heat

Question 33

uncertain futures - economic growth

Answer 33

- after 2008 financial crisis, was predicted that CO2 emissions would rise - but emmission rates fell to 0.5% in 2014

Question 34

uncertain futures - energy sources

Answer 34

- energy consumption grew by 2% between 2008-2014 - renewable sources made up of 2/3 of increase in electricity production

Question 35

uncertain futures - population change

Answer 35

- increasing affluence means extra billion consumers by 2050 - changing diets, increased mobility

Question 36

permafrost

Answer 36

when melted releases carbon into atmosphere - greenhouse gas effect

Question 37

peatlands

Answer 37

accumulation of partly decayed vegetation, low rate of carbon breakdown in cold waterlogged soils, warming of 4c causes 40% loss of soil organic carbon in shallow peat

Question 38

Paris 2015 agreement

Answer 38

- 195 countries promised to reduce greenhouse gas emmisions by almost 0 by 2065 - aimed to limit temperature increase to 1.5 degrees celcius

Question 39

1988

Answer 39

UNEP formed, WMO provide science advice on climate change

Question 40

1992

Answer 40

Earth Summit meeting in Brazil

Question 41

1997

Answer 41

Kyoto protocol

Question 42

2007

Answer 42

Nobel peace prize went to IPCC and ALGore for climate change

Question 43

2014

Answer 43

IPCC reports made all countries reduce emmissions