TY - JOUR

T1 - Climate change-induced vegetation change as a driver of increased subarctic biogenic volatile organic compound emissions

AU - Valolahti, Hanna Maritta

AU - Kivimäenpää, Minna

AU - Faubert, Patrick

AU - Michelsen, Anders

AU - Rinnan, Riikka

N1 - CENPERMOA[2015]

PY - 2015

Y1 - 2015

N2 - Emissions of biogenic volatile organic compounds (BVOCs) have been earlier shown to be highly temperature sensi-tive in subarctic ecosystems. As these ecosystems experience rapidly advancing pronounced climate warming, weaimed to investigate how warming affects the BVOC emissions in the long term (up to 13 treatment years). We alsoaimed to assess whether the increased litterfall resulting from the vegetation changes in the warming subarctic wouldaffect the emissions. The study was conducted in a field experiment with factorial open-top chamber warming andannual litter addition treatments on subarctic heath in Abisko, northern Sweden. After 11 and 13 treatment years,BVOCs were sampled from plant communities in the experimental plots using a push–pull enclosure technique andcollection into adsorbent cartridges during the growing season and analyzed with gas chromatography–mass spec-trometry. Plant species coverage in the plots was analyzed by the point intercept method. Warming by 2 °C caused a2-fold increase in monoterpene and 5-fold increase in sesquiterpene emissions, averaged over all measurements.When the momentary effect of temperature was diminished by standardization of emissions to a fixed temperature,warming still had a significant effect suggesting that emissions were also indirectly increased. This indirect increaseappeared to result from increased plant coverage and changes in vegetation composition. The litter addition treat-ment also caused significant increases in the emission rates of some BVOC groups, especially when combined withwarming. The combined treatment had both the largest vegetation changes and the highest BVOC emissions. Theincreased emissions under litter addition were probably a result of a changed vegetation composition due to allevi-ated nutrient limitation and stimulated microbial production of BVOCs. We suggest that the changes in the subarcticvegetation composition induced by climate warming will be the major factor indirectly affecting the BVOC emissionpotentials and composition.

AB - Emissions of biogenic volatile organic compounds (BVOCs) have been earlier shown to be highly temperature sensi-tive in subarctic ecosystems. As these ecosystems experience rapidly advancing pronounced climate warming, weaimed to investigate how warming affects the BVOC emissions in the long term (up to 13 treatment years). We alsoaimed to assess whether the increased litterfall resulting from the vegetation changes in the warming subarctic wouldaffect the emissions. The study was conducted in a field experiment with factorial open-top chamber warming andannual litter addition treatments on subarctic heath in Abisko, northern Sweden. After 11 and 13 treatment years,BVOCs were sampled from plant communities in the experimental plots using a push–pull enclosure technique andcollection into adsorbent cartridges during the growing season and analyzed with gas chromatography–mass spec-trometry. Plant species coverage in the plots was analyzed by the point intercept method. Warming by 2 °C caused a2-fold increase in monoterpene and 5-fold increase in sesquiterpene emissions, averaged over all measurements.When the momentary effect of temperature was diminished by standardization of emissions to a fixed temperature,warming still had a significant effect suggesting that emissions were also indirectly increased. This indirect increaseappeared to result from increased plant coverage and changes in vegetation composition. The litter addition treat-ment also caused significant increases in the emission rates of some BVOC groups, especially when combined withwarming. The combined treatment had both the largest vegetation changes and the highest BVOC emissions. Theincreased emissions under litter addition were probably a result of a changed vegetation composition due to allevi-ated nutrient limitation and stimulated microbial production of BVOCs. We suggest that the changes in the subarcticvegetation composition induced by climate warming will be the major factor indirectly affecting the BVOC emissionpotentials and composition.

U2 - 10.1111/gcb.12953

DO - 10.1111/gcb.12953

M3 - Journal article

C2 - 25994223

VL - 21

SP - 3478

EP - 3488

JO - Global Change Biology

JF - Global Change Biology

SN - 1354-1013

IS - 9

ER -