To better understand the emission of biogenic volatile organic compounds (BVOCs) in suburbs, we selected 12 typical deciduous fruit trees and conducted field sampling and laboratory analysis of BVOCs using a dynamic sampling technique. To our knowledge, details of BVOC emissions for nine of the selected fruit tree species are reported here for the first time. Emissions of BVOCs from fruit trees contained nine kinds of compounds, including hydrocarbons, alcohols, and aldehydes, of which hydrocarbons accounted for up to 39.0%. All fruit trees were found to emit isoprene and monoterpenes (six species also emitted sesquiterpenes), of which three species were high emitters and nine species, such as Catalpa, were medium emitters. The emission rates of total BVOCs (including isoprene, monoterpenes, and sesquiterpenes) from different fruit trees ranged from (2.6±0.1) μg·(g·h)-1 to (14±0.8) μg·(g·h)-1. Analyses of BVOCs from different families and plant forms indicated that isoprene emission rates were significantly higher from woody fruit trees[(4.2±1.4) μg·(g·h)-1] than from vine fruit trees[(0.6±0.2) μg·(g·h)-1, P=0.03], whereas there was no significant difference between family or genus. This suggests that the emission level of BVOCs from fruit trees cannot be classified by family and genera. In contrast to coniferous plants, β-myrcene, D-limonene, and γ-terpinene-associated with floral or resinous aromas-were the main monoterpenes of fruit trees. The emission rate of β-myrcene was highest, accounting for 59.3% of the total monoterpene emissions. In addition, fruit trees may emit eight other fragrant VOCs listed as hazardous air pollutants (HAPs), e.g., fluorene, phenanthrene, and naphthalene. This study expands the field of BVOCs research and provides basic data for enriching the BVOCs database, as well as for evaluating the environmental effects of BVOCs.
Keywords: biogenic volatile organic compounds (BVOCs); emission characteristics; emissions inventory; fruit tree; hazardous air pollutants (HAPs).