Total Tree Canopy: 1,256 acres (31.0%)
Total Urbanized Area: 2,589 acres (63.9%)
The City of Fairfax, VA
Have you “hugged a tree today?”
Air Pollution Removal
By absorbing and filtering out atmospheric nitrogen
dioxide (NO2), sulfur dioxide (SO2), ozone (O3),
carbon monoxide (CO), and other very small
particles through their stomata, urban trees perform
a vital air cleaning service that directly affects the
well-being of urban dwellers. It is estimated that
the annual air pollution removal by trees in a small
city (such as the City of Fairfax) can save
$300,000 in health expenditures and reduced
tourism revenue.
(Do you know what a stoma is?**)
Carbon Storage
Trees remove carbon dioxide from the air through
their leaves and store carbon in their cells.
Approximately half of a tree’s dry weight, in fact,
is carbon. Large-scale tree planting projects are
recognized as an important tool in many national carbon-reduction programs. It is estimated that the carbon
storage capacity of trees within a small city (City of Fairfax) could be as high as 54,000 tons yearly (1.08 x 108
pounds a year )
(Do you know how a green plant stores carbon?*)
Water Quantity and Quality (Runoff)
Trees decrease total storm water volume which helps cities to manage their storm water and decrease treatment
costs. Trees filter surface water and prevent erosion, both of which maintain or improve water quality. Trees
could save a small city (City of Fairfax) over $ 600,000 per year in water treatment expense and helps to keep
toxic chemicals such as cadmium, lead, and chromium out of the drinking water
Can you think of other important ways in which trees impact our environment?
Did you know:
If you burn 3 gallons of gas during one day of commuting to and from work, the amount of carbon dioxide that you
put into the air is about 30 kg, or 66 pounds.. Carbon dioxide is more dense that oxygen. Without the filtering
capacity of the green plants around us, we would soon find that the oxygen needed for survival would be replaced
by the carbon dioxide and other harmful pollutants from the exhaust of automobiles.
**Stomata are small pores on the bottom of leaves; their opening is controlled by 2 guard cells. When they are open, the stomata
allow gas exchange, mainly CO2 for photosynthesis and H2O, between the leaf and the atmosphere.
* six molecules of water plus six molecules of carbon dioxide produce one molecule of sugar plus six molecules of oxygen and energy
to fuel plant growth (with the aid of the pigment, chlorophyll )