The Effect of Autumnal Moth Induced Volatile Organic Compound Emissions to Aerosol Load in Subarctic Region

Visa fullständig post



Permalänk

http://urn.fi/URN:NBN:fi-fe201902286673
Titel: The Effect of Autumnal Moth Induced Volatile Organic Compound Emissions to Aerosol Load in Subarctic Region
Författare: Ylivinkka, Ilona
Medarbetare: Helsingfors universitet, Matematisk-naturvetenskapliga fakulteten
Utgivare: Helsingin yliopisto
Datum: 2019
Språk: eng
Permanenta länken (URI): http://urn.fi/URN:NBN:fi-fe201902286673
http://hdl.handle.net/10138/299774
Nivå: pro gradu-avhandlingar
Ämne: Meteorologia
Abstrakt: Volatile organic compounds (VOCs) are hydrocarbons that are emitted to the atmosphere from biogenic or anthropogenic sources. Plants emit VOCs as a part of normal metabolism, but the emissions are significantly increased under stressed conditions. For example heat wave, drought and herbivory cause stress for the plants. Laboratory studies have shown that VOCs emitted by herbivory infested boreal forest trees have enhanced secondary organic aerosol (SOA) production. In this study, 25 years (1992–2016) of atmospheric data from measurement site in eastern Finnish Lapland was analyzed to understand wheter the enhancement is atmospherically relevant. The knowledge is important, as aerosol particles cause changes in radiative forcing, and thus contribute to the climate change. At the study site autumnal moth (Epirrita autumnata) larvae are prominent defoliator of mountain birches (Betula pubescens spp. czerepanovii). Autumnal moths have cyclic population dynamics, and during the severe population outbreaks, they can consume all the leaves of mountain birches in vast regions. Despite the severity of the herbivory to the local ecosystem, the analysis did not show connection between the number of autumnal moths and aerosol processes. Also, no clear correlation between the total number concentration and temperature, and hence the basal VOC emissions from biogenic sources, was observed. Nor did sulfur dioxide or sulfuric acid concentration have strong correlation with total particle concentration which would have been expected. The results indicate that probably the total biomass of mountain birches is too small to cause detectable changes in atmospheric variables. Additionally, the study period had only one severe population outbreak during which the data availability of atmospheric variables was limited. However, climate change proceeds fast in the Arctic region. Hence, the basal VOC emissions from vegetation will increase. Also, both the mountain birches and new moth species will expand to the areas where they did not earlier succeed. In the future the enhancement of autumnal moth larvae feeding may be atmospherically relevant.


Filer under denna titel

Totalt antal nerladdningar: Laddar...

Filer Storlek Format Granska
Ylivinkka_Ilona_Pro_gradu_2019.pdf 14.78Mb PDF Granska/Öppna

Detta dokument registreras i samling:

Visa fullständig post