Support systems KQ4- To what extent are the water and carbon cycles linked? Flashcards
(42 cards)
Name 5 strategies used to protect the global carbon cycle
- Wetland restoration
- Agricultural practices
- Afforestation
- International agreements to reduce carbon emissions
- Cap and trade
What are wetlands?
An area where the water table at or near the surface causing the ground to be permanently saturated
How much of the Earth’s land surface is covered by wetlands?
6-9%
How much of the Earth’s terrestrial carbon pool do wetlands hold?
35%
Why are wetlands under pressure?
Population growth, economic development, and urbanisation
How many tonnes of carbon do wetlands hold per ha per year?
3.25
What has been done on the Canadian prairies in regard to wetlands?
112,000 ha have been targeted for restoration, which should eventually sequester 364,000 tonnes of carbon per year
What is being done in the UK in regard to wetland restoration?
-400 ha of grade 1 farmland in East Cambridgeshire is being converted back to wetland
How are wetlands restored?
- local water tables are raised to create water-logged conditions
- flood and sea defences can be breached to water-log areas
- drainage ditches are blocked or diverted
What is afforestation?
The planting for trees in deforested areas or in areas that have never been forested before
Why is wetland restoration needed?
- To reduce carbon dioxide levels in the atmosphere as they act as an important carbon sink
- To conserve wildlife
How can afforestation manage the global carbon cycle?
- trees act as a carbon sink
- so can reduce atmospheric CO2 levels
On what time scale can afforestation have an effect on the carbon cycle?
Medium and long term
Besides reducing CO2 concentration, what other benefits does afforestation provide?
- reducing flood risks
- reducing soil erosion
- increasing biodiveristy
Besides afforestation what can be done to decrease the rate of deforestation?
-tropical forests can be protected from loggers, farmers, and miners
What is the UN doing to combat deforestation? Give examples of areas
- The REDD scheme incentivises developing countries to conserve their rainforests by placing a monetary value on forest conservation
- E.g Amazonia and lower Mississippi
Why are the Chinese government sponsoring an afforestation project?
- to combat desertification and land degradation
- to reduce carbon dioxide emissions
Give examples of unsustainable agricultural practices
- overcultivation
- overgrazing
How many million tonnes a year of methane is released from livestock?
100 million
What 3 general methods can be used to improve agricultural practices?
- Land and crop management
- Livestock management
- Manure management
How does manure management reduce emissions of greenhouse gas?
- controls the way manure decomposes to reduce CH4 emissions
- capturing CH4 as a source of renewable energy
How can livestock management reduce emissions of greenhouse gas?
-improving the quality of animal feed to reduce ENTERIC fermentation so less is converted to CH4
How can land and crop management reduce emissions of greenhouse gas?
- zero tillage, not ploughing soil, preserving soil’s organic content, and reducing oxidation
- growing crops interspersed with trees to protect from soil erosion
How can international agreements reduce carbon emissions?
- The Paris agreement gets countries to set a voluntary target for carbon emissions
- Richer countries transfer money and technologies to poorer countries to assist them in achieving their targets
