Source apportionment of size-segregated atmospheric particles based on the major water-soluble components in Lecce (Italy).

摘要: Atmospheric aerosols have potential effects on human health, the radiation balance, climate, and visibility. The understanding of these requires detailed knowledge aerosol composition size distributions how different sources contribute to particles sizes. In this work, samples were collected using a 10-stage Micro-Orifice Uniform Deposit Impactor (MOUDI). Measurements taken between February October 2011 in an urban background site near Lecce (Apulia region, southeast Italy). Samples analysed evaluate concentrations water-soluble ions (SO42 −, NO3−, NH4+, Cl−, Na+, K+, Mg2 + Ca2 +) organic inorganic carbon. characterised by two modes, accumulation mode having mass median diameter (MMD) 0.35 ± 0.02 μm, representing 51 ± 4% coarse (MMD = 4.5 ± 0.4 μm), 49 ± 4% aerosols. data used estimate losses impactor comparison with low-volume sampler. average loss MOUDI-collected was 19 ± 2%, largest observed for NO3− (35 ± 10%). Significant Ca2 + (16 ± 5%), SO42 − (19 ± 5%) K+ (10 ± 4%), whereas Na+ negligible. Size-segregated source apportionment performed Positive Matrix Factorization (PMF), which applied separately (size interval 1–18 μm) 0.056–1 μm) modes. PMF model able reasonably reconstruct concentration each size-range. uncertainties due evaluated. mode, it not possible distinguish traffic contribution from other combustion sources. efficiently separate nitrate crustal/resuspension origin.