Center for Global Environmental Research, National Institute for Environmental Studies, Tsukuba 3058506, Japan.
Research Faculty of Agriculture, Hokkaido University, Sapporo, 0608589, Japan.
Environ Pollut. 2019 Nov;254(Pt A):112949. doi: 10.1016/j.envpol.2019.07.117. Epub 2019 Jul 26.
In this study, various remote sensing data, modeling data and emission inventories were integrated to analyze the tempo-spatial distribution of biomass burning in mainland Southeast Asia and its effects on the local ambient air quality from 2001 to 2016. Land cover changes have been considered in dividing the biomass burning into four types: forest fires, shrubland fires, crop residue burning and other fires. The results show that the monthly average number of fire spots peaked at 34,512 in March and that the monthly variation followed a seasonal pattern, which was closely related to precipitation and farming activities. The four types of biomass burning fires presented different tempo-spatial distributions. Moreover, the monthly Aerosol Optical Depth (AOD), concentration of particulate matter with a diameter less than 2.5 μm (PM) and carbon monoxide (CO) total column also peaked in March with values of 0.62, 45 μg/m and 3.25 × 10 molecules/cm, respectively. There are significant correlations between the monthly means of AOD (r = 0.74, P < 0.001), PM concentration (r = 0.88, P < 0.001), and CO total column (r = 0.82, P < 0.001) and the number of fire spots in the fire season. We used Positive Matrix Factorization (PMF) model to resolve the sources of PM into 3 factors. The result indicated that the largest contribution (48%) to annual average concentration of PM was from Factor 1 (dominated by biomass burning), followed by 27% from Factor 3 (dominated by anthropogenic emission), and 25% from Factor 2 (long-range transport/local nature source). The annually anthropogenic emission of CO and PM from 2001 to 2012 and the monthly emission from the Emission Database for Global Atmosphere Research (EDGAR) were consistent with PMF analysis and further prove that biomass burning is the dominant cause of the variation in the local air quality in mainland Southeast Asia.
在这项研究中，综合了各种遥感数据、建模数据和排放清单，以分析 2001 年至 2016 年期间东南亚大陆生物质燃烧的时空分布及其对当地环境空气质量的影响。在将生物质燃烧分为森林火灾、灌丛火灾、农作物残余物燃烧和其他火灾四种类型时，已考虑到土地覆盖变化。结果表明，火灾点的月平均数量在 3 月达到峰值，为 34512 个，月变化遵循季节性模式，与降水和农业活动密切相关。四种类型的生物质燃烧火灾呈现出不同的时空分布。此外，气溶胶光学深度（AOD）、直径小于 2.5μm 的颗粒物（PM）浓度和一氧化碳（CO）总柱每月也在 3 月达到峰值，分别为 0.62、45μg/m 和 3.25×10 分子/cm。AOD（r=0.74，P<0.001）、PM 浓度（r=0.88，P<0.001）和 CO 总柱（r=0.82，P<0.001）的月平均值与火灾季节的火灾点数量之间存在显著相关性。我们使用正定矩阵因子分解（PMF）模型将 PM 源解析为 3 个因子。结果表明，对 PM 年平均浓度贡献最大的是因子 1（主要由生物质燃烧产生），占 48%，其次是因子 3（主要由人为排放产生），占 27%，因子 2（远距离传输/本地自然源）占 25%。2001 年至 2012 年的 CO 和 PM 的年人为排放量以及 EDGAR 排放数据库的每月排放量与 PMF 分析一致，进一步证明生物质燃烧是东南亚大陆当地空气质量变化的主要原因。
