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Wednesday, September 4, 2013



1. What is carbon sequestration?
Carbon sequestration refers to the process of capturing carbon dioxide from the atmosphere and storing it (usually in other forms of carbon) for a long period of time.

2. More specifically, it refers to:
Intentional removal of CO2 from the atmosphere and its deposition in a reservoir/carbon sink.
Removal of CO2 from flue gases (e.g in power/process plants) and its storage in a reservoir.
Natural cycling/exchange of carbon from the atmosphere to reservoir and vice versa (carbon cycle).

3. It is an established fact that global warming is on the rise.
This is mainly caused by an increase in greenhouse gases, of which CO2 forms a major part.
Studies have also shown that since the beginning of industrial revolution to 1992, CO2 levels in the atmosphere increased by 30%.
The main reasons attributed to this are change in land use and combustion of fossil fuels.

4. Global warming has negative effects on our planet, such as climatic changes and extreme weather which in turn cause floods, typhoons, a decrease in food production, among others.
The purpose of carbon sequestration is to alleviate global warming so as to avert the occurrence of dangerous/ extreme climatic changes.

5. The methods employed to effect carbon sequestration include…

6. Biological processes
Peat blocs – creating of new peat bogs or by augmenting existing ones.
Reforestation – trees and forest vegetation use CO2(photosynthesis)
Wetland Restoration – wetland soil acts as an important carbon sink.
Agriculture – growing crops act as a carbon sink.
Iron and urea fertilization in oceans

7. Physical processes
Bio-energy from biomass
Biomass burial
Ocean storage of dead biomass brought in by rivers
These processes prevent exposure of dead biomass to the atmosphere, which could otherwise result in release of carbon contained in it to CO2.

8. Chemical processes
Industrial Use – e.g in beverage industries.
Chemical Scrubbers – in process industries to prevent escape of CO2 to the atmosphere.


10. Biomass refers to the biological material obtained either from living plants or from plants that were recently living. Aboveground biomass therefore includes all plant matter above the soil surface, for instance:
Trees – parts above the soil; stem, leaves, branches.
Growing Crops – parts above the soil, excludes all parts below the soil.
Decaying agricultural and forest waste on the soil surface.

11. Aboveground biomass has a two-way effect on carbon sequestration…

12. On one hand;
Living plants utilize CO2 in photosynthesis, converting it into other forms of carbon useful for their growth.
This aids in carbon sequestration.

13. On the other hand;
Decaying plant matter on the soil surface loses carbon to the atmosphere in form of CO2
This has a reverse effect on carbon sequestration

14. 1. Type and density of vegetation
Different vegetation types have different potential of carbon sequestration.
For instance, tropical forests have been found to have a greater potential as compared to dry evergreen and mixed deciduous forests.

15. 2. Size of plants
Different plant sizes have different potential of carbon sequestration.
Plants that grow to greater sizes utilize more CO2 for their growth and thus they have a greater carbon sequestration potential than smaller plants.
For instance, trees have a greater potential than crops like beans or maize plants.

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