Responses of Plants to Submicron Acid Aerosols

摘要: A continuous flow system for exposing vegetation to submicron sulfuric acid aerosols was developed. The were mechanically produced using a nebulization-impaction-neutralization process. Typical aerosol distributions had mass mean diameter of about 0.5 μm and standard geometric deviation near 1.7. Plants injured during acute exposures aerosols. However, the concentrations required produce visible injury significantly higher than measured ambient concentrations. All species exposed exhibited marginal tip necrosis or interveinal necrosis. plant responses did not follow proportional relations pollutant dose (concentration X time). Lack dosage suggested that active rather passive mechanisms may be controlling response. In tissue no increase in leaf surface sulfur could detected. On contrary, there an internal levels.