Monitoring changes in the sulphur isotopic composition and concentration of transplanted pendulous epiphytic lichens.

摘要

Little is known about the response of lichens to sudden changes in the concentration and source of sulphur in the atmosphere despite an interest in lichens as tools in environmental monitoring. A transplant study was performed to determine this response in two species of pendulous epiphytic lichens by monitoring changes in their sulphur isotopic composition and sulphur concentration. Branches covered with the lichens, Alectoria sarmentosa and Bryoria capillaris, were taken from the Bonavista Peninsula and transplanted into the Memorial University of Newfoundland (MUN) Botanical Garden, St. John's. Two separate transplant experiments were performed between June 1997 and September 1998. Experiment I involved monthly sampling from June 1997 to June 1998. Experiment II involved weekly sampling from June 1998 to September 1998.;This investigation is the first attempt to monitor lichen response to changing atmospheric conditions using stable sulphur isotopes. It has provided essential information for further lichen studies and sulphur isotopic studies in particular. It also has important implications for environmental monitoring and assessment. (Abstract shortened by UMI.).