Investigating evidence of enhanced aerosol formation and growth due to autumnal moth larvae feeding on mountain birch at SMEAR I in northern Finland

• Main Authors: Ylivinkka, Ilona, Itämies, Juhani, Klemola, Tero, Ruohomäki, Kai, Kulmala, Markku, Taipale, Ditte
• Other Authors: INAR Physics, Global Atmosphere-Earth surface feedbacks, Institute for Atmospheric and Earth System Research (INAR)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Finnish Environment Institute 2021
• Subjects: 114 Physical sciences; ATMOSPHERIC NUCLEATION; BIOGENIC EMISSIONS; CLIMATE-CHANGE; EPIRRITA-AUTUMNATA; LEAF-AREA INDEX; OPEROPHTERA-BRUMATA; ORGANIC AEROSOL; OXIDATION-PRODUCTS; PARTICLE FORMATION EVENTS; VOLATILE ISOPRENOIDS; Boreal Environment Research; Northern Finland
• Online Access: http://hdl.handle.net/10138/325232

Laboratory studies have shown that heibivory-induced biogenic volatile organic compound (BVOC) emissions might enhance aerosol formation and growth. To increase understanding of the atmospheric relevance of this enhancement, we analyzed 25 years of data from SMEAR I (Station for Measuring Ecosystem-Atmosphere Relations) in northern Finland, where autumnal moth (Epirrita autumnata) larvae are prominent defoliators of mountain birch. We did not find a direct correlation between the autumnal moth density and aerosol processes, nor between the total number concentration and temperature, and hence the basal BVOC emissions. Instead, there is some evidence that the total particle concentration is elevated even for a few years after the infestation due to delayed defense response of mountain birch. The low total biomass of the trees concomitantly with low autumnal moth densities during most of the years of our study, may have impacted our results, hindering the enhancement of aerosol processes. Peer reviewed