Effects of Reducing the Ambient UV-B Radiation in the High Arctic on Salix arctica and Vaccinium uliginosum.
Research output: Contribution to journal › Journal article › Research › peer-review
Standard
Effects of Reducing the Ambient UV-B Radiation in the High Arctic on Salix arctica and Vaccinium uliginosum. / Albert, Kristian; Ro-Poulsen, Helge; Mikkelsen, Teis Nørgaard; Bredahl, L.; Haakansson, K.B.
In: Phyton, Vol. 45, No. 4, 2005, p. 41-49.Research output: Contribution to journal › Journal article › Research › peer-review
Harvard
APA
Vancouver
Author
Bibtex
}
RIS
TY - JOUR
T1 - Effects of Reducing the Ambient UV-B Radiation in the High Arctic on Salix arctica and Vaccinium uliginosum.
AU - Albert, Kristian
AU - Ro-Poulsen, Helge
AU - Mikkelsen, Teis Nørgaard
AU - Bredahl, L.
AU - Haakansson, K.B.
PY - 2005
Y1 - 2005
N2 - Effects of reducing the ambient UV-B radiation on gas exchange and chlorophyll fluores-cence of two dwarf shrub species, Salix arctica and Vaccinium uliginosum, was studied in a high arctic heath in North East Greenland during two growing seasons. Films (Mylar, transmitting ¿ > 320 nm, and Lexan, transmitting ¿ > 400 nm) were used to reduce UV-B radiation and UV-B+A respectively. A UV transparent film (Teflon, transmitting ¿ > 280 nm) and no film were used as controls. Field measurements showed that the plants under Teflon, Mylar and Lexan received app. 91%, 39% and 17% of the ambient UV-B irradiance, respectively. UV radiation decreased the maximal photochemical efficiency (Fv/Fm) and other fast fluorescence transient derived parameters in both species, despite an increased level of leaf flavonoid content. The responses varied in signifi-cance according to species and site. The relation of these effects to a significantly decreased stomatal conductance (gs) and intercellular CO2 concentration (Ci) pointed to respiration as an im-portant factor in the interpretation of the observed unaffected net CO2 assimilation (Pn) in UV- re-duced treatments. It is concluded that the studied species have not fully acclimatized to the level of ambient UV-B radiation, and that ambient UV-B level is an important stress factor for the investi-gated plants in High Arctic.
AB - Effects of reducing the ambient UV-B radiation on gas exchange and chlorophyll fluores-cence of two dwarf shrub species, Salix arctica and Vaccinium uliginosum, was studied in a high arctic heath in North East Greenland during two growing seasons. Films (Mylar, transmitting ¿ > 320 nm, and Lexan, transmitting ¿ > 400 nm) were used to reduce UV-B radiation and UV-B+A respectively. A UV transparent film (Teflon, transmitting ¿ > 280 nm) and no film were used as controls. Field measurements showed that the plants under Teflon, Mylar and Lexan received app. 91%, 39% and 17% of the ambient UV-B irradiance, respectively. UV radiation decreased the maximal photochemical efficiency (Fv/Fm) and other fast fluorescence transient derived parameters in both species, despite an increased level of leaf flavonoid content. The responses varied in signifi-cance according to species and site. The relation of these effects to a significantly decreased stomatal conductance (gs) and intercellular CO2 concentration (Ci) pointed to respiration as an im-portant factor in the interpretation of the observed unaffected net CO2 assimilation (Pn) in UV- re-duced treatments. It is concluded that the studied species have not fully acclimatized to the level of ambient UV-B radiation, and that ambient UV-B level is an important stress factor for the investi-gated plants in High Arctic.
M3 - Journal article
VL - 45
SP - 41
EP - 49
JO - Phyton - Annales Rei Botanicae
JF - Phyton - Annales Rei Botanicae
SN - 0079-2047
IS - 4
ER -
ID: 86863