RESUMO
Topsoil (0-20 cm) samples (n=101) in 5 different land use types in Shenyang North New Area (SNNA), Shenyang, China were collected using the uniform grid layout method to investigate the spatial distribution characteristics, composition spectrum, and source analysis of 16 polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants by the Environmental Protection Agency of the United States. Results showed that the total concentration of the 16 PAHs (ΣPAHs) in soils of SNNA ranged from 123.7 µg·kg-1 to 932.5 µg·kg-1. The PAH components were mainly dominated by 3-ring and 4-ring PAHs, of which the proportion of 3-ring PAHs was the highest. The spatial distribution of the ΣPAHs concentration was obvious, showing a decreasing tendency from south to north and from east to west. In the five soil types, the average concentrations of the ΣPAHs were relatively higher in the urban green space and the artificial forest, followed by the vegetable land, while the total PAH concentrations in paddy fields and corn fields were relatively lower and had no obvious spatial distribution differences. Source apportionment results studied using characteristic ratio analysis and factor analysis/multivariate linear regression showed that the main sources of PAHs in the topsoil of SNNA were mixed sources. Industrial coal combustion and motor vehicle exhaust were the main PAH contributors, with a combined contribution rate of 79.6%. The oil spill and coke oven contribution rate was about 16.2%, and the biomass fuel combustion was about 4.2%.
