Nairobi National park covers an area of 4,200 acres. It boarders Langata road, Magadi road and Mombasa road very close to the city.
The park is 4,200 acres of grassland. Forest land is 10 times as effective in cleaning the air of carbon dioxide as grassland. The huge tree trunks serve as carbon sinks where carbon dioxide is removed form the air and stored as tree trunks and oxygen is released for us to breath.
Assuming a tree spacing of 700 trees per acre, the 4,200 acre land will contain at least 3 million trees.
According to the research below
From the calculations below, 1 acre of forest stores 50.8 tonnes of carbon in form of leaves, bark, trunk/wood.
Trees’ Carbon Sequestration
The first step in determining how much carbon is sequestered by a single tree is to convert carbon to carbon dioxide (CO2) or carbon dioxide equivalent (CO2e). For our calculations, we used the common conversion of:
1 ton of carbon = 3.666 tons of CO2
This represents the weight of carbon dioxide (44) divided by the atomic mass of carbon (12). Next, it is estimated that one acre of trees stores 50.8 metric tons of carbon, so…
50.8 metric tons of carbon X 3.666 tons of CO2 = ~186 metric tons of CO2 per acre of forest
Since we don’t use metric tons as a common measurement in the U.S., we next need to convert tons to pounds:
1 metric ton = 2204.62262 pounds
186 metric tons X 2204.62262 pounds = ~410,060 pounds of CO2 sequestered per acre of trees
American Forests has estimated that our tree planting projects average 450 trees per acre, which leaves us with one final calculation:
410060 pounds of CO2/450 trees per acre = ~911 pounds of CO2 sequestered per tree planted.
This translates to 186 tonnes of carbon dioxide being removed from the atmosphere to prevent the Green house gasses effect on the environment.
Tropical savannahs remove/store 13 tonnes of Carbon from the environment per year compared to 54 tonnes removed by trees/forests.
This means, as a means to protect our environment better from CO2 greenhouse effects, and to clean off CO2 from Nairobi , forest cover will be more effective than the grassland at Nairobi National park.
Karen residential estate, next to Nairobi National park, has a high density of forest cover hence better placed at cleaning the environment than the grassland at the park.
An acre of forest absorbs CO2 from approximately 3 cars. 4200 acres this will help absorb CO2 from 12,600 cars.
Jogoo road has an estimated traffic volume of 80,000 cars per day according to this article below
Langata road has less than this so the forest will help clean a considerable chunk of air in the Langata, South c and Rongai regions.
The infrastructure surrounding it along Magadi road, Mombasa road and Langata road has cost the Kenyan tax payer billions of shillings.
It would only be feasible if the billions spent can be recovered back to the economy through ensuring better environmental harmony.
Going forward, methods to establish the 4,200 acre Nairobi National park as a forest should be researched into.
A practical method to achieve this would be to lease the land in parcels of 1 acre to developers who are then restricted to using a maximum of 5% of the 1 acre plot to construct a building , then the 95% of the remainder to be fully covered by trees. Nairobi County Government and the Kenya Forestry service can then enforce this and terminate the lease of anyone flouting these rules.
The disadvantage of this is that in future, this can be used to grab the land and re change the rules , thereby creating higher ground building coverages and cutting off the trees. This would require a very strict policing and a very mature and understanding lessee who understands the benefits of the forest to the environment.
Another way is for the Kenya Forestry service to move in and plant trees and continue to maintain the park as it is, as both a national park and a forest at the same time.
Francis Gichuhi Kamau, Architect.