Biogenic particles in the surface microlayer and overlaying atmosphere in the central Arctic Ocean during summer
Biogenic particles in the surface microlayer and overlaying atmosphere in the central Arctic Ocean during summer
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DOI：
10.3402/tellusb.v57i4.16546
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发表时间：
2005-01
期刊：
影响因子：
--
通讯作者：
C. Leck;E. Bigg
中科院分区：
文献类型：
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作者：
C. Leck;E. Bigg
空气中的颗粒的透射电子显微镜照片进行了比较，在北冰洋中部的浮冰之间的开放水域的表面微层中发现的颗粒在夏季。在形态、物理性质、X射线光谱和化学反应方面的相似性表明，大量聚集体及其主要直径小于70 nm的构建块，以及在两者中发现的细菌和其他微生物，强烈表明空气中的颗粒是通过破裂气泡从水中喷射出来的。团聚体在空气中的粒径分布形状与在水中非常相似，都具有明确的Aitken模式，但向更小的尺寸移动。扩散电子透明材料连接和周围的耐热和非吸湿颗粒在空气和水中被证明具有与微藻和细菌的胞外聚合物分泌物（EPS）在水中一致的属性。EPS是高度表面活性的、高度水合的分子，可以自发地组装成凝胶。它们被紫外线或酸化分解。这些性质提供了一个解释的differentiresistance脱水细菌从空气和水样品时，受到真空，和明显absenceof海盐对空气中的细菌和聚集体。本文还解释了空气和水样品在粒度分布上的差异。研究了大气中的EPS和铅微层颗粒物在大气中产生艾特肯模式粒子和云凝结核中的作用，并得出结论：EPS和颗粒物在大气中产生艾特肯模式粒子和云凝结核中是非常重要的。
Transmission electron microscopy photographs of airborne particles are compared with those of particles found inthe surface microlayer of the open water between ice floes in the central Arctic Ocean in summer. The similarity inmorphology, physical properties, X-ray spectra and a chemical reaction of the numerous aggregates and their buildingblocks predominantly smaller than 70 nm diameter, and of bacteria and other micro-organisms found in both, stronglysuggests that the airborne particles were ejected from the water by bursting bubbles. The shape of the size distribution ofaggregates in the air is very similar to that in the water, each with a well-defined Aitken mode but shifted towards smallersizes. Diffuse electron-transparent material joining and surrounding the heat resistant and non-hygroscopic particulatesin both the air and water is shown to have properties consistent with the exopolymer secretions (EPS) of microalgae andbacteria in the water. EPS are highly surface-active, highly hydrated molecules that can spontaneously assemble intogels. They are broken down by ultraviolet light or acidification. These properties provide an explanation for the differentresistance to dehydration of bacteria from air and water samples when subjected to a vacuum, and the apparent absenceof sea salt on airborne bacteria and aggregates. The difference in size distribution between the air and water samples isalso explained. The role of EPS and particulate matter from the open lead surface microlayer in the production of theairborne Aitken mode particles and cloud condensation nuclei is examined and concluded to be very important.