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Kevin E. Percy Sirkku Manninen Karl-Heinz Häberle H. Werner Rainer Matyssek 《Environmental pollution (Barking, Essex : 1987)》2009,157(5):1657-1665
We examined the effect of ozone (O3) on Norway spruce (Picea abies) needle epicuticular wax over three seasons at the Kranzberg Ozone Fumigation Experiment. Exposure to 2× ambient O3 ranged from 64.5 to 74.2 μl O3 l−1 h AOT40, and 117.1 to 123.2 nl O3 l−1 4th highest daily maximum 8-h average O3 concentration. The proportion of current-year needle surface covered by wax tubes, tube aggregates, and plates decreased (P = 0.011) under 2× O3. Epistomatal chambers had increased deposits of amorphous wax. Proportion of secondary alcohols varied due to year (P = 0.004) and O3 treatment (P = 0.029). Secondary alcohols were reduced by 9.1% under 2× O3. Exposure to 2× O3 increased (P = 0.037) proportions of fatty acids by 29%. Opposing trends in secondary alcohols and fatty acids indicate a direct action of O3 on wax biosynthesis. These results demonstrate O3-induced changes in biologically important needle surface characteristics of 50-year-old field-grown trees. 相似文献
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The exposure of greenhouse workers to deltamethrin and dichlorvos was studied when low‐volume misters (LVM) were used for the application of these insecticides. Exposure to deltamethrin was mainly by skin contamination and the level of exposure was low. Exposure to dichlorvos was clearly higher than to deltamethrin both through skin and inhalation. These two insecticides are different from chemical structure and character dichlorvos being a highly volatile chemical. The re‐entry period for deltamethrin was calculated to be about ten hours and for dichlorvos two or three days. 相似文献