Dose-response relationships for SO2 fumigations in the lichens Evernia prunastri (L.) Ach. and Ramalina fraxinea (L.) Ach

• Published in: The New phytologist 1992-10, Vol.122 (2), p.313-319
• Main Authors: Sanz, M.J, Gries, C, Nash, T.H. III
• Format: Article
• Language: English
• Subjects: air pollution; Animal, plant and microbial ecology; Applied ecology; Biological and medical sciences; chemical constituents of plants; chlorophyll; chlorophylls; dose‐response relationships; Ecotoxicology, biological effects of pollution; Effects of pollution and side effects of pesticides on plants and fungi; Fundamental and applied biological sciences. Psychology; indicator species; Lichens; net assimilation rate; photosynthesis; Quercus pyrenaica; respiration; sulfur dioxide; sulphur dioxide; water content
• ISSN: 0028-646X; 1469-8137
• DOI: 10.1111/j.1469-8137.1992.tb04236.x

SUMMARY Sulphur dioxide fumigation of the lichens Evernia prunastri (L.) Ach and Ramalina fraxinea (L.) Ach, whose thallus water content was held at 100‐120%, throughout each experiment, resulted in changes in net photosynthesis, dark respiration and chlorophyll content in relation to both concentration and duration of exposure. Net photosynthesis was the most sensitive response variable. Significant reduction in chlorophyll content was found when no recovery in net photosynthesis occurred after two weeks. A reduction in dark respiration was only found at high SO2 concentrations. Evernia prunastri was affected by lower concentrations and shorter exposure times than Ramalina fraxinea and the data for both species showed dose‐response relationships.