Produce enough oxygen on each acre for 18 people every day. . Absorb enough CO2 on each acre, over a year's time, to equal the amount you produce when you drive your car 26,000 miles. Trees remove gaseous pollutants by absorbing them through the pores in the leaf surface. Particulates are trapped and filtered by leaves, stems and twigs, and washed to the ground by rainfall. They also weaken trees making them more susceptible to other health problems such as insects and diseases.
Ozone is a major pollutant in smog.
The burning of fossil fuels for energy and large scale forest fires such as in the tropics are major contributors to the buildup of CO2 in the atmosphere. Managing and protecting forests and planting new trees reduces CO2 levels by storing carbon in their roots and trunk and releasing oxygen into the atmosphere. The greenhouse effect is created when heat from the sun enters the atmosphere and is prevented from radiating back into space by air-polluting gases. The buildup of about 40 heat-trapping gases is created mostly by human activities. Heat buildup threatens to raise global temperatures to levels unprecedented in human history.