An appreciation of trees
|Trees in our yards and in our communities add to the global |
population, which is crucial for slowing down climate change.
Here are just some of the many ways that trees are important not only in our urban and suburban neighborhoods, but also for the whole planet:
- Trees actually cool the air through transpiration. A mature deciduous tree like an oak will transpire more than 400 liters of water on a hot summer's day. In the process of liquid water evaporating (going from liquid to gas) the air is cooled. At 68˚F each gram of water that evaporates, cools the air by 585 calories. Transpiration: Forests' most important service
- Trees sequester carbon, by absorbing carbon dioxide (CO2) a long-lasting greenhouse gas, through the process of photosynthesis where they remove carbon dioxide from the air to make sugars, which are then stored in the various plant tissues. A typical hardwood tree can absorb as much as 48 pounds of carbon per year. This means it will sequester approximately 1 ton of carbon by the time it reaches 40 years old. Carbon sequestration
- Trees produce oxygen through photosynthesis, but trees and all the other organisms in the forest absorb most of that oxygen to live. Also read Transpiration: Forests' most important service where I talk about three cycles in the forest: Carbon, Oxygen, and Water.
- Trees remove carbon monoxide (CO) and other air pollutants from the air. They are absorbed primarily through stomata (pores) on the leaves where they diffuse into intercellular spaces and may be absorbed by water films to form acids or react with inner-leaf surfaces. Trees can remove significant amounts of air pollution in cities, where it is often concentrated. More information on this from the EPA.