9508417 Claiborn Atmospheric hydrogen peroxide plays important roles in tropospheric photochemistry and in converting sulfur dioxide to sulfuric acid in cloudwater, and may also be toxic to vegetation. The interactions between plants and atmospheric hydrogen peroxide are of interest to both the atmospheric and plant sciences communities. While quantification of its dry deposition rates to vegetation is necessary for photochemical models, there have been very few studies that have attempted to measure deposition of hydrogen peroxide to plants. In previous work it was demonstrated that it is possible, in both field and laboratory experiments, to measure hydrogen peroxide with adequate precision to enable calculation of fluxes. In this work, it is proposed to adapt a more direct measure of the flux, the relaxed eddy accumulation (REA) method, to measure hydrogen peroxide fluxes over a forest canopy. Then, over a three-year period, the principal investigator will conduct two types of experiments: 1) field measurements of deposition rates of hydrogen peroxide to forest canopies, and 2) controlled chamber experiments on individual saplings representing some of the same species found in the forest studies. By conducting both experiments, it will be possible to both quantify the deposition rate to the canopy under the environmental conditions of the experiment, and to predict how the deposition rate changes with changing environmental conditions. The education plan is based upon three main objectives. Like the proposed research plan, the education plan emphasizes the cross-disciplinary nature of environmental studies. Development of both undergraduate and graduate courses that emphasize the cross-media behavior of pollutants and that draw upon several sciences including chemistry, biology, atmospheric sciences, and engineering, is planned. The second objective is to improve communication skills of engineering students, both at the graduate and undergraduate levels. The third objective is to improve retention of students, particularly from underrepresented groups.
