Brief Summary of Minutes of Annual Meeting

Long and short term monitoring: The establishment of long term monitoring programs combining analytical measurements with in field plant indicator species allows for evaluating plant health from ozone and other atmospheric contaminants. It allows for risk assessors and managers to have a gauge as to whether restrictions on atmospheric inputs are resulting in less leaf toxicity in sensitive species. Recommendations for the planting of certain less sensitive species would be encouraged in order to reduce leaf damage until ozone levels are sufficiently reduced. Educational opportunities: Developing hands on activities designed for younger students to obtain an understanding of atmospheric impacts on sensitive plant species. In the case of Penn State a 3 credit summer course in this area is taught to teachers for maintaining accreditation for teacher certification. Research: The results from studies conducted at the various participating organizations allows for an exchange of information and a broad discussion on the mechanism by which ozone and other atmospheric contaminants damage plant species. The results in a variety of species demonstrate the variability in sensitivity of the different plant species. Specific information that was discussed at the meeting included: 1) base information on impacts on nutrient quality of grasses with Trifolian species experiencing increased sensitivity 2) species sensitivity may be related to stomatal density and aperture allowing varying amounts of ozone entering the plant leaf 3) long term exposure of approximately a week between 50-60 ppm ozone causes significant damage 4) CO2 can ameliorate ozone toxicity at certain concentrations 5) ascorbate may be another factor that can modulate toxicity and 6) Arabidopsis and several mutants have provided insight into genes and pathways involved in species sensitivity.