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Northern Research Station
11 Campus Blvd., Suite 200
Newtown Square, PA 19073
(610) 557-4017
(610) 557-4132 TTY/TDD

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  [photo] Down woody materials creating a waterfall.

Ozone Biomonitoring Program


Monitoring our nations air quality using natural indicators is called Biomonitoring.  FIA uses biomonitoring to monitor the potential impact of tropospheric ozone (smog) on forests.  


What is ground level ozone?

Ground level ozone is an air pollutant in the lower atmosphere formed from the reactions of hydrocarbons and nitrous oxides in the presence of sunlight. Automobile engines and industrial processes produce most of the compounds that result in ozone. It is a major element of urban smog. The airborne transport of ozone to remote forested areas has led to increasing concern about how this pollutant is influencing the health of our national forests. Possible impacts of ozone on forested species include reduced growth and seed production and increased susceptibility to insects and disease. Long-term ozone stress may lead to changes in species composition and biodiversity. Link to EPA .

What is a bioindicator plant?

Bioindicators are plants that exhibit a visible response to ozone pollution. A useful bioindicator plant may be a tree, a woody shrub, or a non-woody herb species. The essential characteristic is that the species respond to ambient levels of ozone pollution with distinct visible foliar symptoms that are easy to diagnose. . Check out the bioindicator species in your area !

What is ozone biomonitoring?

One way to monitor the impact of ozone on our forest resource is to use bioindicator plants to detect and quantify ozone stress in the forest environment. A nationwide network of ozone biomonitoring sites has been established across the forested landscape. Each year these sites are evaluated for the amount and severity of ozone injury on sensitive plants. The foliar injury data is used to monitor changes in relative air quality over time and to examine relationships between ozone stress and tree health.



Last Modified: 03/28/2007

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  • Plants are more sensitive than humans to ozone pollution. Unlike humans, the effects of ozone on plants is both cumulative and long-term. The general public is mostly unaware of the sensitivity of plants to ozone. Data from the ozone biomonitoring network in FIA will help to inform future discussions about how best to protect the environment from ozone....