EFFECTS OF UV RADIATION ON THE SUCCESSION OF BENTHIC COMMUNITIES IN SPITSBERGEN

• Main Authors: Fricke, Anna, Molis, Markus, Wiencke, Christian, Valdivia, Nelson, Chapman, A. S.
• Format: Conference Object
• Language: unknown
• Published: 2007
• Subjects: Arctic; Kongsfjord*; Kongsfjorden; Spitsbergen
• Online Access: https://epic.awi.de/id/eprint/17408/; https://hdl.handle.net/10013/epic.27755

At present there is very little information how macrobenthic communities are affected by UV radiation. In particular, it is not clear whether the damaging effects of UV radiation can be buffered by ecological processes. In the present study, a field experiment in the intertidal of the Arctic Kongsfjorden (78°55N, 11°56E) in Spitsbergen was conducted from 12 May to 10 July 2006, and the individual and interactive effects of UV-radiation and successional age of macrobenthic communities, developed over different time periods in the sublittoral, were investigated. Communities were transplanted from their original place at 8 m water depth onto floating constructions in 0.5 m water depth and exposed for a period of 4 and 8 weeks to different light treatments: PAR (400-700nm), PAR+UVA (320-700nm), PAR+UVA+UVB (280-700nm) and full sunlight (control). Macrobenthic species composition, biodiversity, percentage cover and biomass (dry mass) were analyzed. Additionally, the light regime in the atmosphere and at 50cm water depth was monitored constantly. The results show that increased solar radiation after transfer from deep to shallow water, as well as UV radiation, affected the succession of macrobenthic communities. The differential spectral ranges tested showed negative as well as positive effects. Observed differences between the communities can be explained by the different UV tolerances and the interactions between the different species. In conclusion, older communities seemed to be more stable in their composition than younger ones: