泥炭地野火对大气中吸收光的有机碳的释放做出了重要贡献,通常被称为棕色碳。在这项研究中,我们研究了西太平洋海洋气溶胶中含氮有机化合物(NOC)的存在,受到东南亚泥炭地火灾的影响。在电喷雾电离(ESI)正模式下采用超高分辨率傅里叶变换离子回旋共振质谱(FT-ICRMS),我们发现NOC主要由还原的含氮碱基组成,包括CHN+和CHON+组。值得注意的是,与典型的海洋气团相比,泥炭地野火的羽流中NOC公式的数量显着增加。这些NOC,通常被鉴定为N-杂环生物碱,作为潜在的光吸收发色团。此外,许多NOC表现出热解稳定性,参与各种取代反应,并显示出增强的亲水性能,归因于化学过程,如甲氧基化,羟基化,甲基化,以及在排放和随后的大气老化过程中发生的氢化。在白天的大气传输过程中,芳香N-杂环化合物的老化,特别是在容易氧化和与胺反应的脂族胺中,被观察到。调查结果强调了泥炭地野火在增加海洋气溶胶中含氮有机物方面的关键作用,强调需要深入研究它们对海洋生态系统和区域气候条件的影响。
Peatland wildfires contribute significantly to the atmospheric release of light-absorbing organic carbon, often referred to as brown carbon. In this study, we examine the presence of nitrogen-containing organic compounds (NOCs) within marine aerosols across the Western Pacific Ocean, which are influenced by
peatland fires from Southeast Asia. Employing ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in electrospray ionization (ESI) positive mode, we discovered that NOCs are predominantly composed of reduced nitrogenous bases, including CHN+ and CHON+ groups. Notably, the count of NOC formulas experiences a marked increase within plumes from
peatland wildfires compared to those found in typical marine air masses. These NOCs, often identified as N-heterocyclic alkaloids, serve as potential light-absorbing chromophores. Furthermore, many NOCs demonstrate pyrolytic stability, engage in a variety of substitution reactions, and display enhanced hydrophilic properties, attributed to chemical processes such as methoxylation, hydroxylation, methylation, and hydrogenation that occur during emission and subsequent atmospheric aging. During the daytime atmospheric transport, aging of aromatic N-heterocyclic compounds, particularly in aliphatic amines prone to oxidation and reactions with amine, was observed. The findings underscore the critical role of
peatland wildfires in augmenting nitrogen-containing organics in marine aerosols, underscoring the need for in-depth research into their effects on marine ecosystems and regional climatic conditions.