To better understand the characteristics of biomass burning in the northern Indo-Gangetic Plain (IGP), total suspended particles were collected in a rural site, Lumbini, Nepal, during April?2013 to March?2014 and analyzed for the biomass burning tracers (i.e., levoglucosan, mannosan, vanillic acid). The annual average concentration of levoglucosan was 734?±?1043?ng?m?3 with the maximum seasonal mean concentration during post-monsoon season (2206?±?1753?ng?m?3), followed by winter (1161?±?1347?ng?m?3), pre-monsoon (771?±?524?ng?m?3) and minimum concentration during monsoon season (212?±?279?ng?m?3). The other biomass burning tracers (mannosan, galactosan, p-hydroxybenzoic acid, vanillic acid, syringic acid and dehydroabietic acid) also showed the similar seasonal variations. There were good correlations among levoglucosan, organic carbon (OC) and elemental carbon (EC), indicating significant impact of biomass burning activities on carbonaceous aerosol loading throughout the year in Lumbini area. According to the characteristic ratios, levoglucosan?∕?mannosan (lev?∕?man) and syringic acid?∕?vanillic acid (syr?∕?van), we deduced that the high abundances of biomass burning products during non-monsoon seasons were mainly caused by the burning of crop residues and hardwood while the softwood had less contribution. Based on the diagnostic tracer ratio (i.e., lev?∕?OC), the OC derived from biomass burning constituted large fraction of total OC, especially during post-monsoon season. By analyzing the MODIS fire spot product and 5-day air-mass back trajectories, we further demonstrated that organic aerosol composition was not only related to the local agricultural activities and residential biomass usage but also impacted by the regional emissions. During the post-monsoon season, the emissions from rice residue burning in western India and eastern Pakistan could impact particulate air pollution in Lumbini and surrounding regions in southern Nepal. Therefore, our finding is meaningful and has a great importance for adopting the appropriate mitigation measures, not only at the local level but also by involving different regions and nations, to reduce the biomass burning emissions in the broader IGP region nations.
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机译：为了更好地了解北部难以荷兰语平原（IGP）的生物质燃烧的特征，在4月至3月至3月的农村遗址，尼泊尔在农村遗址，尼泊尔队进行了总悬浮颗粒？2014年，并分析了生物量燃烧示踪剂（即，左葡葡萄酒，人群，香草酸）。年平均液浓度为734°？±1043？ng？m？3？3在季风季节（2206？±1753°？1753？n≤3）中，最大季节性平均浓度，其次是冬季（1161？± ？1347？ng？m？3），季隆前（771〜±524〜524？n≤m≤3）和季风季节期间的最小浓度（212〜±279？ng≤m≤3）。其他生物质燃烧的示踪剂（甘露南，半乳糖，对羟基苯甲酸，香草，注射酸和脱氢酸）也显示出类似的季节变化。 Levoglucosan，有机碳（OC）和元素碳（EC）之间存在良好的相关性，表明生物量燃烧活性对莱热地区全年含碳气溶胶荷载量的显着影响。根据特征比，左葡聚糖呢？/？甘露治（Lev？/？男人）和注射酸？/？香草酸（SYR？/？范），我们推导出在非季风季节期间的生物质燃烧产品的高度丰富主要是由作物残留物和硬木燃烧，而软木贡献较少。基于诊断示踪率（即，LEV？/ oc），oc来自生物质燃烧的oc构成大部分总OC，特别是在季风季节期间。通过分析Modis Fire Spect产品和5天的空气质量后轨迹，我们进一步证明了有机气溶胶组合物不仅与当地农业活动和住宅生物量使用有关，也受到区域排放的影响。在季风季节期间，印度西部和巴基斯坦东部燃烧的水稻残留物的排放可能会影响尼泊尔南部伦尼尼和周边地区的微粒空气污染。因此，我们的结论是有意义的，有采用适当的缓解措施，不仅在地方一级，但也涉及到不同地区和国家，以减少生物质燃烧在更广泛的IGP区域各国的排放具有重要意义。
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