Dynamic characteristics of biogenic volatile organic compounds in typical subtropical forests and it’s relationship with environmental factors

This study aimed to investigate the temporal dynamics of biogenic volatile organic compounds (BVOCs) in four typical subtropical forest types, and to provide theoretical support for the development of forest therapy resources.

Mixed broadleaved forest, Phoebe forest, Chinese fir plantation, and Moso bamboo plantation were selected as study objects, and the composition and relative mass concentrations of major BVOCs were analyzed in May, August, and October, and their correlations with temperature, relative humidity, and air negative ions were examined.

The results showed that BVOCs exhibited the highest diversity in mixed broadleaved forest (79 species), compared to 69 species in other forest types. All four forest types released similar BVOCs components, predominantly alkanes, terpenes, and aldehydes (11-19 species each), with aromatic hydrocarbons and aldehydes being the most abundant (15%-35% of total emissions). Among the 19 terpenoid compounds detected, α-pinene was the dominant component. The mixed broadleaved forest showed significantly higher relative mass concentrations of terpenes than other forests, peaking in May. Both BVOCs diversity and relative mass concentrations displayed distinct seasonal patterns: the mixed broadleaved forest, Phoebe forest, and Chinese fir plantation showed maximum component richness in May and minimum in August, while the opposite trend was observed in moso bamboo plantation. Peak relative mass concentrations occurred in May and October for mixed broadleaved forest and Phoebe forest, but in August and October for Chinese fir plantation and moso bamboo plantation. Additionally, BVOCs emissions were primarily negatively correlated with temperature, relative humidity, and air negative ions.

Among the four subtropical forest types, the mixed broadleaved forest had the richest BVOCs composition and the highest relative concentrations of health-beneficial terpenes, particularly peaking in May. Therefore, forest therapy activities during this period may yield optimal therapeutic effects.