ACTIVITY OF LICHENS UNDER THE INFLUENCE OF SNOW AND ICE

• Main Author: Burkhard Schroeter
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Antarctic; Antarc*
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.626.6004; http://polaris.nipr.ac.jp/~penguin/polarbiosci/issues/pdf/1997-Kappen.pdf

Abstract: A major aim of our investigations is to explain the adaptation of vegetation to the peculiar environmental conditions in polar regions. Our concept describes the main limiting and favorable factors influencing photosynthetic production of cryptogams, mainly lichens. Snow and ice-usually stress factors to the activity of p l a n t s ~ c a n be effectively used by lichens because of their poikilohydrous nature. Light, the basic driving force for photosynthetic activity, may be deleterious under certain circumstances of the cold environment. In moderate climates the summer season is most favorable to plant activity and production and is therefore called the growing season. In the continental Antarctic as well as in the high Arctic region the favorable light and temperature conditions during the summer period may not be as profitable to the productivity of lichens as expected because water is deficient. As in many arid regions, climatic conditions during transient seasons (early summer, fall) merit greater attention if lichen activity is considered and investigated. Our way of investigating this is to establish measuring systems that automatically record micro-environmental parameters and lichen activity over the whole annual period. Another is to investigate physiological responses of lichens to the environmental conditions with experiments mainly carried out in the field. 1.