Articles | Volume 13, issue 21
Research article
04 Nov 2016
Research article |  | 04 Nov 2016

BVOC emissions from English oak (Quercus robur) and European beech (Fagus sylvatica) along a latitudinal gradient

Ylva van Meeningen, Guy Schurgers, Riikka Rinnan, and Thomas Holst

Abstract. English oak (Quercus robur) and European beech (Fagus sylvatica) are amongst the most common tree species growing in Europe, influencing the annual biogenic volatile organic compound (BVOC) budget in this region. Studies have shown great variability in the emissions from these tree species, originating from both genetic variability and differences in climatic conditions between study sites. In this study, we examine the emission patterns for English oak and European beech in genetically identical individuals and the potential variation within and between sites. Leaf scale BVOC emissions, net assimilation rates and stomatal conductance were measured at the International Phenological Garden sites of Ljubljana (Slovenia), Grafrath (Germany) and Taastrup (Denmark). Sampling was conducted during three campaigns between May and July 2014.

Our results show that English oak mainly emitted isoprene whilst European beech released monoterpenes. The relative contribution of the most emitted compounds from the two species remained stable across latitudes. The contribution of isoprene for English oak from Grafrath and Taastrup ranged between 92 and 97 % of the total BVOC emissions, whilst sabinene and limonene for European beech ranged from 30.5 to 40.5 and 9 to 15 % respectively for all three sites. The relative contribution of isoprene for English oak at Ljubljana was lower (78 %) in comparison to the other sites, most likely caused by frost damage in early spring. The variability in total leaf-level emission rates from the same site was small, whereas there were greater differences between sites. These differences were probably caused by short-term weather events and plant stress. A difference in age did not seem to affect the emission patterns for the selected trees.

This study highlights the significance of within-genotypic variation of BVOC emission capacities for English oak and European beech, the influence of climatic variables such as temperature and light on emission intensities and the potential stability in relative compound contribution across a latitudinal gradient.

Short summary
English oak and European beech are common European trees known to release volatile compounds such as isoprene and monoterpenes. By doing leaf chamber measurements at three sites in Europe, the aim was to study how the emission differed for cloned trees growing at different sites. The measured emission rates from clones varied between sites, but the relative compound contribution was stable both within and between sites. This can help to increase our knowledge of emission pattern variability.
Final-revised paper