Diurnal Variation and Chemical Characteristics of Atmospheric Aerosol Particles and Their Source Fingerprints at Xiamen Bay

Abstract

This study investigated the diurnal variation of mass concentration and chemical composition of atmospheric aerosol particles sampled at Xiamen Bay, located on the west bank of the Taiwan Strait. Atmospheric PM 10 samples were collected at ten particulate matter (PM) sampling sites at Xiamen Bay, including five sites at the Kinmen Islands and five sites in urban Xiamen, at both daytime and nighttime during the regular and intensive sampling periods. Regular sampling was conducted to collect PM 10 with high-volume samplers three times a month from April 2009 to April 2010, while intensive sampling was conducted to collect PM 2.5 and PM 2.5-10 with dichotomous samplers in the spring and winter of 2009 and 2010. This study further selected ten major emission sources (e.g., stone processing, power plants, soil dusts, and biomass burning) at Xiamen Bay to collect fugitive particulate samples which were then resuspended in a self-designed resuspension chamber to collect PM 2.5 and PM 2.5-10 with two separate dichotomous samplers for further chemical analysis.The results from PM 10 sampling indicated that atmospheric aerosol particles tended to be accumulated in Xiamen Bay all year round, but especially in spring and winter. A significant diurnal variation of PM 10 was observed, with higher PM 10 concentrations in the daytime during the regular sampling periods. The chemical analysis results showed that the major chemical components of PM 10 were SO 4 2-, NO 3 -, NH 4 + , OC, EC, and crustal elements (Ca, Mg, Fe, and Al), which were usually higher in the daytime than at night at Xiamen Bay. The differences were most pronounced at night, where the concentrations of most anthropogenic elements (Ni, Cu, As, and V) were higher than those in the daytime. The elemental composition of PM emitted from stone processing and the cement industry were dominated by crustal elements, particularly Ca, whereas the profile of top-soil mainly contained Al and Ca. The profiles of industrial sources were dominated by secondary inorganic aerosols and EC. Moreover, construction and road dusts contained large amounts of Fe and Al, while biomass burning released large amounts of K, OC, and SO 4 2-.

Scavenging and fractionation of particle-reactive radioisotopes 7Be, 210Pb and 210Po in the atmosphere

“…Fig. 5 presents the diagrams of the daytime and nighttime wind roses, showing the seasonal changes of the prevailing wind direction and wind speed at the study site (Li et al, 2013). These diagrams indicate that at our study site, the prevailing winds are the southwesterly (from the South China Sea and tropical oceans) in the spring and summer and the northeasterly (from the Asian continent) in the fall and spring (Li et al, 2013).…”

Modelling of long-range transport of Southeast Asia biomass-burning aerosols to Taiwan and their radiative forcings over East Asia

“…Biomass-burning aerosols were predominantly fine particles (PM 2.5 ), which constitute a high proportion of PM 10 concentration. The PM 2.5 /PM 10 ratio at Xiamen Bay in China (Li et al, 2013), Thailand (Oanh et al, 2011), Korea (Ryu et al, 2007), and central Taiwan (Cheng et al, 2009) were found to be as high as 90, 79, 90 and 80%, respectively. Note that these findings are close to the simulated results in this study.…”

Seasonal Variation and Chemical Characteristics of Atmospheric Particles at Three Islands in the Taiwan Strait

“…Since the detailed descriptions of CMB receptor model (e.g., CMB 8.0) are available elsewhere, only a brief summary is presented as supplementary file S1-1 and Table S-3. Ten major local source profiles (noted by * in Table S-3) obtained from previous studies were selected to conduct the source apportionment of PM 10 in this study (Li et al, 2013b). These sources surrounding the Xiamen Bay included stone processing, cement industries, ceramic plants, tile industries, coal burning, coal ash, fugitive dusts, biomass burning, construction dusts, and road dusts as shown in Table S-3.…”