The influence of UV-B radiation on light-dependent photosynthetic performance in Sanionia uncinata (Hedw.) Loeske in Antarctica

Photosynthetic activity of the moss Sanionia uncinata (Hedw.) Loeske was investigated on Léonie Island (67°35'S, 68°20'W, Antarctic Peninsula) in response to short-term changes of UV-B radiation. The UV-environment of natural mat formations dominated by S. uncinata was altered using filter...

Full description

Saved in:
Bibliographic Details
Published in:Polar biology 2003-04, Vol.26 (4), p.225-232
Main Authors: LUD, D, SCHLENSOG, M, SCHROETER, B, HUISKES, A. H. L
Format: Article
Language:English
Subjects:
Animal and plant ecology
Animal, plant and microbial ecology
Autoecology
Biological and medical sciences
Ecology
Fundamental and applied biological sciences. Psychology
Islands
Mosses
Photosynthesis
Plants and fungi
Ultraviolet radiation
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Photosynthetic activity of the moss Sanionia uncinata (Hedw.) Loeske was investigated on Léonie Island (67°35'S, 68°20'W, Antarctic Peninsula) in response to short-term changes of UV-B radiation. The UV-environment of natural mat formations dominated by S. uncinata was altered using filter screens. Two filter experiments were conducted in the Antarctic summers 1998 and 1999. A third filter experiment was conducted during springtime ozone depletion in October 1998. Photosynthetic activity of S. uncinata was mainly determined by photosynthetically active photon flux density (PPFD). Light response of relative electron transport rate through photosystem II (rel ETR=ΔF/Fm'×PPFD) remained unaffected by ambient summer levels of UV-B radiation. The same was found for net photosynthesis and dark respiration. In October 1998, S. uncinata was mainly metabolically inactive due to low temperatures. No significant levels of DNA-damage measured as cyclobutane pyrimidine dimers (CPDs) were induced by ambient summer levels of UV-B. Artificially enhanced UV-B radiation supplying a Setlow-DNA-dose of 8.7 kJ m^sup -2^ day^sup -1^ UV-B led to formation of 7±3 CPD (10^sup 6^ nucleotides)^sup -1^. It is concluded that current ambient summer levels of UV-B radiation do not affect photosynthetic activity in S. uncinata.[PUBLICATION ABSTRACT]
ISSN:0722-4060
1432-2056
DOI:10.1007/s00300-003-0480-5