Schiestl-Aalto, Pauliina
- Institutionen för skogens ekologi och skötsel, Sveriges lantbruksuniversitet
- Helsingin yliopisto
Forskningsartikel2020Vetenskapligt granskadÖppen tillgång
Taipale, Ditte; Aalto, Juho; Schiestl-Aalto, Pauliina; Kulmala, Markku; Back, Jaana
Models to predict the emissions of biogenic volatile organic compounds (BVOCs) from terrestrial vegetation largely use standardised emission potentials derived from shoot enclosure measurements of mature foliage. In these models, the potential of new foliage to emit BVOCs is assumed to be similar, or up to twice as high, as that of mature foliage, and thus new conifers foliage is predicted to have a negligible to minor contribution to canopy BVOC emissions during spring time due to the small foliage mass of emerging and growing needles. Extensive observations have, however, recently demonstrated that the potential of new Scots pine needles to emit several different BVOCs can be up to about 500 times higher than that of the corresponding mature foliage. Thus, we build on these discoveries and investigate the potential impact of considering these enhanced emissions from new Scots pine foliage on estimates of monoterpene emissions and new atmospheric aerosol particle formation and their subsequent growth. We show that the importance of taking the enhanced monoterpene emission potential of new Scots pine foliage into account decreases as a function of season, tree age and latitude, and that new foliage could be responsible for the majority of the whole tree's foliage emissions of monoterpenes during spring time, independently of tree age and location. Our results suggest that annual monoterpene emission estimates from Finland would increase with up to similar to 25% if the enhanced emissions from new Scots pine foliage were also considered, with the majority being emitted during spring time where also new particle formation has been observed to occur most frequently. We estimate that our findings can lead to increases in predictions of the formation rates of 2 nm particles during spring time by similar to 75-280% in northern Finland and by similar to 130-870% in southern Finland. Likewise, simulated growth rates of 2-3 nm particles would increase by similar to 65-180% in northern Finland and by similar to 110-520% in southern Finland if the enhanced emissions of monoterpenes from new Scots pine foliage were explicitly considered. Since only one measurement study (Aalto et al., 2014), on which our work builds, has so far found highly pronounced emissions of monoterpenes from new Scots pine foliage compared to those of mature, we conclude that more spring time measurements of new conifers foliage are required for improving emission algorithms in biogenic emission models.
Scots pine; Monoterpenes; Plant volatile emission; Forest growth; Finland
Atmospheric Environment: X
2020, Volym: 8, artikelnummer: 100097Utgivare: ELSEVIER SCI LTD
Miljövetenskap
DOI: https://doi.org/10.1016/j.aeaoa.2020.100097
https://res.slu.se/id/publ/123121