Abstract:
High population and a wide range of activities in a megacity lead to large-scale ecological consequences which require the assessment with respect to distinct characteristics of climate, location, fuel consumption, and emission sources. In-depth study of aerosol characteristics was carried out in Moscow, the largest megacity in Europe, during the cold period (autumn and winter) and in spring. PM10 chemical speciation based on carbonaceous matter, water-soluble ions, and elements was carried out to reconstruct the PM mass and evaluate the primary and secondary aerosol contribution. For the whole study period organic matter, mineral dust, and secondary inorganic/organic accounted for 34, 24, and 16 % of PM10 mass, respectively. PM10, OC, and EC approached a maximum in spring and decreased in winter. Mineral dust seasonal fraction increased from spring (17 %) to autumn (32 %), and then decreased in winter (22 %). Secondary inorganic aerosols (SIA) in opposite showed the maximum 27 % in winter. K+ marked the residential biomass burning in the region surrounding a megacity in spring and autumn, agriculture fires in spring. In winter primary aerosol contribution dropped down 56 % while secondary approached practically equal 44 %. Source factors with the relative contributions are quantified, namely city dust (26 %), traffic (23 %), industrial (20 %), biomass burning (12 %), secondary (12 %), and de-icing salt (7 %); they were significantly varying between the cold heating period and springtime. The relevance of sources to meteorological parameters and mass transportation is investigated by using both bivariate polar plots and Lagrangian integrated trajectory (HYSPLIT) model. Trajectory clustering demonstrates regional sources being crucial contributors to PM10 pollution. Aerosol speciation and source apportion factors identify the differences of the Moscow urban background among large European and Asian cities due to northern climate conditions, fast construction, long-range transport from industrial-developing area surrounding a city, regional biomass burning preferably in spring and autumn, and winter road management.
摘要:
大城市的人口众多和广泛的活动导致大规模的生态后果,需要对不同的气候特征进行评估。location,燃料消耗,和排放源。莫斯科对气溶胶特性进行了深入研究,欧洲最大的大城市,在寒冷时期(秋季和冬季)和春季。基于含碳物质的PM10化学形态,水溶性离子,并进行了元素来重建PM质量并评估主要和次要气溶胶贡献。对于整个研究期间的有机物,矿物粉尘,和次级无机/有机占PM10质量的34%,24%和16%,分别。PM10,OC,EC在春季达到最大值,冬季下降。从春季(17%)到秋季(32%),矿物粉尘的季节性比例增加,然后在冬季下降(22%)。相反的次生无机气溶胶(SIA)在冬季表现出最大的27%。K+标志着春季和秋季大城市周围地区的住宅生物质燃烧,春季农业火灾。在冬季,主要气溶胶的贡献下降了56%,而次要气溶胶的贡献几乎等于44%。具有相对贡献的来源因素被量化,即城市灰尘(26%),交通(23%),工业(20%),生物质燃烧(12%),次要(12%),和除冰盐(7%);它们在冷加热期和春季之间显着变化。通过使用双变量极图和拉格朗日综合轨迹(HYSPLIT)模型,研究了源与气象参数和大众运输的相关性。轨迹聚类表明区域来源是PM10污染的关键贡献者。气溶胶形态和来源比例因素确定了由于北方气候条件,欧洲和亚洲大城市之间莫斯科城市背景的差异,快速施工,来自城市周围工业发展地区的长途运输,区域生物质燃烧最好在春季和秋季,冬季道路管理。