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Acid mist and ozone effects on the leaf chemistry of two western conifer speciesThe effects of ozone and acid-mist exposures on the leaf chemistry of Jeffrey pine and giant sequoia seedlings grown in filtered-air greenhouses were investigated. Acid-mist treatments (pH 4.1, 3.4, 2.7, or 2.0) were administered for 3 h, and ozone exposures (0, 0.10, and 0.20 microliter/liter), which followed acid-mist treatments, for 4 h, each for three days a week for six to nine weeks. It was found that seedlings were more susceptible to acid-mist and acid mist/ozone combinations, than to ozone alone. Acid mist treatment resulted in higher levels of nitrogen and sulfur (both present in acid mist) as well as Na. Leaves of giant sequoia exhibited increased K and decreased Mn, while Jeffrey pine showed increases in Fe and Mn. In sequoia leaves, concentrations of Ca, Mg, and Ba decreased. Acid treatment also reduced chlorophyll b concentrations in both conifer species. Extensive changes induced by acid mist are consistent with earlier observations of changes in spectral reflectance of conifer seedlings observed after three weeks of fumigation.
Document ID
Document Type
Reprint (Version printed in journal)
Westman, Walter E. (NASA Ames Research Center Moffett Field, CA, United States)
Temple, Patrick J. (California, University Riverside, United States)
Date Acquired
August 14, 2013
Publication Date
January 1, 1989
Publication Information
Publication: Environmental Pollution
Volume: 57
ISSN: 0269-7491
Subject Category
Distribution Limits