Changes in the factors influencing forest floor BVOC emissions during forest succession

The files have been uploaded to comply with AGU and journal requirements, particularly the "Open Research" section, which provides links to the data and analytical code necessary for the peer review process. This initiative aims to support transparent and reproducible science. 

Data analysis and the ploting of Figure2 in manuscript, along with Figure S1-S3 and Table S1-S4 in supporting information, were conducted using R Studio. The file "Forest floor BVOC emissions_analyses and plots.R" and datasets "ForestFloor.csv", "boxplot_BVOC_ca.csv", "boxplot_BVOC_fi.csv", "boxplot_BVOC_ru.csv", "SamplingSite_1.csv" were utilized for this purpose.

To generate Figure 3 in the manuscript, the file "SIMCA 18 for Fig 3.dox" and dataset "ForestFloor.xlsx" were used. The word file provide the the trial software link. 

For the analysis and ploting of Figure 4 in the manuscript, the file "PLS_PM.R" and dataset "BVOC_PLSR_PM.csv" were employed. 

The file "For Fig S4.xlsx" was used to create Figure S4 in the supporting information. 

Abstract in article

The boreal forest floor is a crucial source of diverse biogenic volatile organic compounds (BVOCs) emitted into the atmosphere. Climate change is increasing in the frequency of wildfires in the boreal forest, major disturbances with lasting impacts on the ecosystem, particularly the forest floor. Wildfires changed BVOC sources and emissions, influencing aerosol formation during forest succession across various age classes. This study quantified BVOC emissions from the forest floor and characterized microenvironmental conditions, including abiotic factors (air temperature, soil temperature, soil moisture, light intensity) and biotic factors (ground vegetation composition, species coverage, soil respiration). Our objective was to understand how abiotic and biotic factors influence the forest floor BVOC emissions during forest succession. Path models revealed direct influences of ground vegetation composition on isoprene and monoterpene emissions. Sesquiterpene emissions were mainly regulated by abiotic factors, while isoprene and monoterpene emissions were influenced both directly and indirectly by abiotic factors. The indirect impact of abiotic factors was manifested through biotic factors, including vegetation and soil processes. Effect sizes of influencing factors varied across different forest age areas, with temperature exerting a larger impact in earlier burned areas compared to recently burned areas. The influence of soil moisture on BVOC emissions diminished with forest age. Our findings indicated the importance of identifying influencing factors and their relationship with forest floor BVOC emissions during different stages of forest succession for predicting the effect of post-wildfire forest succession on the BVOC emission patterns and, consequently, their impact on climate.