College of Environment and Climate, Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China.
College of Environment and Climate, Institute for Environmental and Climate Research, Jinan University, Guangzhou 511443, China; Guangdong Provincial Observation and Research Station for Atmospheric Environment and Carbon Neutrality in Nanling Forests, China; Australia-China Centre for Air Quality Science and Management (Guangdong), Guangzhou 511443, China.
Sci Total Environ. 2024 Dec 1;954:176668. doi: 10.1016/j.scitotenv.2024.176668. Epub 2024 Oct 5.
Biogenic volatile organic compounds (BVOCs) emitted by tropical plants represent a significant proportion of global emissions, but the in-situ BVOC measurements in tropical rainforests are extremely sparse. Herein, a vehicle-mounted mobile monitoring system was developed for in-situ online investigations of BVOC emissions from thirty representative tree species in the tropical rainforests of Hainan Island, southern China. The results showed that monoterpenes were the primary BVOCs emitted from most broadleaf trees. Isoprene, sabinene, γ-terpinene and β-ocimene were the most abundant BVOCs. Localized canopy-scale emission factors (EFs) exhibited notable discrepancies with the defaults in the Model of Emissions of Gases and Aerosols from Nature (MEGAN), specifically with isoprene EFs being slightly lower than the model, while the EFs for monoterpenes and sesquiterpenes were 1 to 27 times higher than those in MEGAN. The BVOC emission inventory for the predominant mature forest species in Hainan Island in 2023 was further estimated to be 244.43 Gg C·yr, with isoprene and monoterpenes accounting for 74 % and 16 %, respectively. Additionally, unimodal monthly variation patterns were revealed, with BVOC emissions peaked in July (30.08 Gg C·yr) and bottomed in January (8.84 Gg C·yr). This study demonstrates the potential and versatility of the applied mobile platform for in-situ online measurements of plant volatiles. Our findings provide important data support for reducing uncertainties in BVOC emission estimations in tropical rainforests and for evaluating their health benefits in the context of forest therapy.
生物源挥发性有机化合物（BVOCs）是热带植物排放的重要组成部分，占全球排放量的很大比例，但热带雨林中现场BVOC 测量却极为稀少。在此，我们开发了一种车载移动监测系统，用于原位在线调查中国海南岛热带雨林中 30 种代表性树种的 BVOC 排放。结果表明，单萜是大多数阔叶树种排放的主要 BVOCs。异戊二烯、柠檬烯、γ-萜品烯和β-罗勒烯是最丰富的 BVOCs。局部冠层尺度排放因子（EFs）与自然排放气体和气溶胶模型（MEGAN）中的默认值存在显著差异，特别是异戊二烯 EFs 略低于模型值，而单萜和倍半萜 EFs 则比 MEGAN 中的 EFs 高 1 到 27 倍。进一步估计，2023 年海南岛主要成熟森林物种的 BVOC 排放清单为 244.43GgC·yr，其中异戊二烯和单萜分别占 74%和 16%。此外，BVOC 排放呈现单峰月变化模式，7 月排放量最高（30.08GgC·yr），1 月最低（8.84GgC·yr）。本研究证明了所应用的移动平台在现场在线测量植物挥发物方面的潜力和多功能性。我们的研究结果为减少热带雨林中 BVOC 排放估算的不确定性以及评估其在森林疗法中的健康效益提供了重要的数据支持。
