Minor long-term effects of ultraviolet-B radiation on methane dynamics of a subarctic fen in Northern Finland

TY - JOUR

T1 - Minor long-term effects of ultraviolet-B radiation on methane dynamics of a subarctic fen in Northern Finland

AU - Mörsky, Sami K.

AU - Haapala, Jaana K.

AU - Rinnan, Riikka

AU - Saarnio, Sanna

AU - Suokanerva, Hanne

AU - Latola, Kirsi

AU - Kyrö, Esko

AU - Silvola, Jouko

AU - Holopainen, Toini

AU - Martikainen, Pertti J.

PY - 2012/4

Y1 - 2012/4

N2 - The effects of elevated ultraviolet-B (UV-B) radiation on methane dynamics was studied in a natural fen in Northern Finland for three growing seasons (2003-2005). This is the first in situ study on the effects of elevated UV-B radiation on methane dynamics in a natural fen. The experimental setup consisted of 30 study plots (120 × 120 cm) that were randomly divided into three treatments: ambient control, UV-A control and elevated UV-B. The UV-B enhancements were 63, 37 and 21% above ambient during the growing seasons 2003, 2004 and 2005, respectively. Elevated UV-B did not affect net methane emission. Stable isotope composition of methane indicated that methane was produced by the acetate fermentation. Under elevated UV-B there was a slight increase in the concentrations of acetate and propionate but decrease in the oxalate concentration suggesting UV-B-induced changes in the belowground processes. The results emphasize the need for long-term field studies under moderately enhanced exposures to estimate whether the function and feedbacks of mire ecosystems change under increased UV-B radiation.

AB - The effects of elevated ultraviolet-B (UV-B) radiation on methane dynamics was studied in a natural fen in Northern Finland for three growing seasons (2003-2005). This is the first in situ study on the effects of elevated UV-B radiation on methane dynamics in a natural fen. The experimental setup consisted of 30 study plots (120 × 120 cm) that were randomly divided into three treatments: ambient control, UV-A control and elevated UV-B. The UV-B enhancements were 63, 37 and 21% above ambient during the growing seasons 2003, 2004 and 2005, respectively. Elevated UV-B did not affect net methane emission. Stable isotope composition of methane indicated that methane was produced by the acetate fermentation. Under elevated UV-B there was a slight increase in the concentrations of acetate and propionate but decrease in the oxalate concentration suggesting UV-B-induced changes in the belowground processes. The results emphasize the need for long-term field studies under moderately enhanced exposures to estimate whether the function and feedbacks of mire ecosystems change under increased UV-B radiation.

U2 - 10.1007/s10533-011-9593-z

DO - 10.1007/s10533-011-9593-z

M3 - Journal article

SN - 0168-2563

VL - 108

SP - 233

EP - 243

JO - Biogeochemistry

JF - Biogeochemistry

IS - 1-3

ER -