Source apportionment of carbonaceous chemical species to fossil fuel combustion, biomass burning and biogenic emissions by a coupled radiocarbon-levoglucosan marker method

作者：Salma Imre; Nemeth Zoltan; Weidinger Tamas; Maenhaut Willy; Claeys Magda; Molnar Mihaly; Major Istvan; Ajtai Tibor; Utry Noemi; Bozoki Zoltan

来源：Atmospheric Chemistry and Physics, 2017, 17(22): 13767-13781.

DOI：10.5194/acp-17-13767-2017

<jats:p>&lt;p&gt;&lt;strong&gt;Abstract.&lt;/strong&gt; An intensive aerosol measurement and sample collection campaign was conducted in central Budapest in a mild winter for 2 weeks. The online instruments included an FDMS-TEOM, RT-OC/EC analyser, DMPS, gas pollutant analysers and meteorological sensors. The aerosol samples were collected on quartz fibre filters by a low-volume sampler using the tandem filter method. Elemental carbon (EC), organic carbon (OC), levoglucosan, mannosan, galactosan, arabitol and mannitol were determined, and radiocarbon analysis was performed on the aerosol samples. Median atmospheric concentrations of EC, OC and PM&lt;sub&gt;2.5&lt;/sub&gt; mass were 0.97, 4.9 and 25&lt;span class="thinspace"&gt;&lt;/span&gt;µg&lt;span class="thinspace"&gt;&lt;/span&gt;m&lt;sup&gt;−3&lt;/sup&gt;, respectively. The EC and organic matter (1.6&lt;span class="thinspace"&gt;&lt;/span&gt; × &lt;span class="thinspace"&gt;&lt;/span&gt;OC) accounted for 4.8 and 37&lt;span class="thinspace"&gt;&lt;/span&gt;%, respectively, of the PM&lt;sub&gt;2.5&lt;/sub&gt; mass. Fossil fuel (FF) combustion represented 36&lt;span class="thinspace"&gt;&lt;/span&gt;% of the total carbon (TC&lt;span class="thinspace"&gt;&lt;/span&gt; = &lt;span class="thinspace"&gt;&lt;/span&gt;EC&lt;span class="thinspace"&gt;&lt;/span&gt;+&lt;span class="thinspace"&gt;&lt;/span&gt;OC) in the PM&lt;sub&gt;2.5&lt;/sub&gt; size fraction. Biomass burning (BB) was a major source (40&lt;span class="thinspace"&gt;&lt;/span&gt;%) for the OC in the PM&lt;sub&gt;2.5&lt;/sub&gt; size fraction, and a substantial source (11&lt;span class="thinspace"&gt;&lt;/span&gt;%) for the PM&lt;sub&gt;10&lt;/sub&gt; mass. We propose and apply here a novel, straightforward, coupled radiocarbon–levoglucosan marker method for source apportionment of the major carbonaceous chemical species. The contributions of EC and OC from FF combustion (EC&lt;sub&gt;FF&lt;/sub&gt; and OC&lt;sub&gt;FF&lt;/sub&gt;) to the TC were 11.0 and 25&lt;span class="thinspace"&gt;&lt;/span&gt;%, respectively, EC and OC from BB (EC&lt;sub&gt;BB&lt;/sub&gt; and OC&lt;sub&gt;BB&lt;/sub&gt;) were responsible for 5.8 and 34&lt;span class="thinspace"&gt;&lt;/span&gt;%, respectively, of the TC, while the OC from biogenic sources (OC&lt;sub&gt;BIO&lt;/sub&gt;) made up 24&lt;span class="thinspace"&gt;&lt;/span&gt;% of the TC. The overall relative uncertainty of the OC&lt;sub&gt;BIO&lt;/sub&gt; and OC&lt;sub&gt;BB&lt;/sub&gt; contributions was assessed to be up to 30&lt;span class="thinspace"&gt;&lt;/span&gt;%, while the relative uncertainty for the other apportioned species is expected to be below 20&lt;span class="thinspace"&gt;&lt;/span&gt;%. Evaluation of the apportioned atmospheric concentrations revealed some of their important properties and relationships among them. EC&lt;sub&gt;FF&lt;/sub&gt; and OC&lt;sub&gt;FF&lt;/sub&gt; were associated with different FF combustion sources. Most EC&lt;sub&gt;FF&lt;/sub&gt; was emitted by vehicular road traffic, while the contribution of non-vehicular sources such as domestic and industrial heating or cooking using gas, oil or coal to OC&lt;sub&gt;FF&lt;/sub&gt; was substantial. The mean contribution of BB to EC particles was smaller by a factor of approximately 2 than that of road traffic. The main formation processes of OC&lt;sub&gt;FF&lt;/sub&gt;, OC&lt;sub&gt;BB&lt;/sub&gt; and OC&lt;sub&gt;BIO&lt;/sub&gt; from volatile organic compounds were jointly influenced by a common factor, which is most likely the atmospheric photochemistry, while primary organic emissions can also be important. Technological improvements and control measures for various BB appliances, together with efficient education and training of their users, in particular on the admissible fuel types, offer an important potential for improving the air quality in Budapest, and likely in other cities as well.&lt;/p&gt;
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• 出版日期2017-11-20