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Abstract: Determination of 14C and levoglucosan can provide insights into the quantification of source contributions to carbonaceous aerosols, yet there is still uncertainty on the partitioning of organic carbon (OC) into biomass burning OC (OCbb) and biogenic emission OC (OCbio). Carbonaceous species, levoglucosan and 14C in PM2.5 were measured at three types of site in southeast China combined with Latin hypercube sampling, with the objectives to study source contributions to total carbon (TC) and their uncertainties, and to evaluate the influence of levoglucosan/OCbb ratios on OCbb and OCbio partitioning. It was found reliably that fossil fuel combustion is the main contributor (62.90–72.23%) to TC at urban and peri-urban sites. Biogenic emissions have important contribution (winter, 52.98%; summer, 45.71%) to TC at background site. With the increase in levoglucosan/OCbb ratios, the contribution of OCbio is increased while OCbb is decreased in a pattern of approximate natural logarithm at a given range. [Copyright &y& Elsevier]

Particulate matter pollution, nowadays, is one of the most concerning environmental problems in Chinese cities, and yet monitoring of PM2.5(aerodynamic diameter of particle ≤2.5 μm) by means of Environmental Internet of Things (EIoT) is still limited in the urbanizing regions in China. A real-time 1 year continuous observation of PM2.5by EIoT was carried out at a coastal site in Xiamen City during 2012, with the objective to explore the temporal variations and possible sources of PM2.5in this urbanizing region. The annual average PM2.5mass concentration was 32.7 ± 9.6 μg m−3, with the highest level in spring (43.6 ± 5.0 μg m−3) and lowest in summer (21.0 ± 2.5 μg m−3). The mean diurnal pattern of PM2.5mass concentrations had an obvious morning peak and low values from midnight to dawn. Additionally, the concentrations on workdays were clearly higher in contrast to those on weekends. These results indicate that particulate matter in this region is mainly influenced by anthropogenic activities, and could be effectively scavenged by precipitation. Pollution rise suggested that particulate matters were mainly from civil engineering during the construction of new urban area. A distinct characteristic of particulate matters in this urbanizing region was the low ratio (0.40) of PM2.5/PM10, which might result from the increment of coarse particles emission from freeways, construction, and sea spray. The outcomes also show that EIoT technology is convenient for the management of particulate matter pollution. [ABSTRACT FROM AUTHOR]