AIR | ABOUT US |  CONTACT US |  FAQ'S | NEWSROOM

Logo of the US Forest Service, Caring for the Land and Serving the People Logo of the US Forest Service, Caring for the Land and Serving the People

 
Air Resource Management Home
Program Spotlight
Wilderness Air Quality
Who We Are
Our Partners
Monitoring and Data
Air Pollution
Law and Policy
Manager's Portal
   
   

USDA Forest Service
1400 Independence Avenue SW
Washington, D.C.
20250-0003
(202) 205-8333

Egov: My Government. My Terms -- The President's E-government Intitatives.

USA dot Gov: The U.S. Government's Official Web Portal.

   

Ozone


Ozone is a colorless gas that exists naturally in the upper atmosphere where it shields the earth from the sunís harmful ultraviolet rays. Ozone close to the earthís surface is an air pollutant. It is formed by chemical reactions between volatile organic compounds (VOCs) and oxides of nitrogen in the presence of sunlight and, often, elevated temperatures. The primary human sources of VOCs and nitrogen oxides are industrial and automobile emissions. Ozone can be transported hundreds of miles to remote areas of the country.

Monitoring Ozone Effects on Forest Health

Ozone leaf showing ozone damage

An example of ozone symptoms on a leaf. Photo courtesy of Sharon Grant.

Ozone is one of the most toxic air pollutants to plants. It causes considerable damage to vegetation throughout the world. Plants are generally more sensitive to ozone than humans. The effects of ozone on native plants in natural ecosystems range from visible injury to the leaves and needles of deciduous trees and conifers to premature leaf loss, reduced photosynthesis, and reduced growth in sensitive plant species. Other factors, such as soil moisture, presence of other air pollutants, insects or diseases, genetics, or topographical locations can lessen or magnify the extent of ozone injury. For example, higher elevations typically see higher ozone exposure levels leaving high elevation vegetation more at risk. Learn more about ozone impacts to forests.

Related Topic: