关键词: 公路, 苹果园, 土壤, 多环芳烃, 尾气污染, 高效液相色谱, 风险评价

Abstract:

To investigate air pollution of the ΣPAHs released by the automobile exhaust we measured the ΣPAHs content in 0-45 cm soil layers of the three apple orchards by the provincial highway S304 in Yantai Qixia by ASE-HPLC. The results showed that automobile exhaust emissions leaded to PAHs pollution to different degrees in the orchard soil within 10-150 m from both sides of the road. The topsoil had the highest PAHs content with more than 1 000 ng·g^-1. The average ΣPAHs content ratio was 1.63:1.35:1 for 0-15, 15-30 and 30-45 cm soil layers. The 11 kinds of PAHs were classed into three types including the change gradually type, the distance spread type and the fluctuation type according to the sink conditions. ΣPAHs of the change gradually type, including Phenanthrene, Fluoranthene and Anthracene, reduced with the increasing distance after 20 m, and their maximum settlement amount reached to 343.93 ng·g^-1, 113.06 ng·g^-1, and 18.11 ng·g^-1. ΣPAHs of the distance spread type, including Pyrene, Benzo[b]fluoranthene, Benzo[a]pyrene, Benzo[a, h]anthracene, increased with the increasing distance, and the maximum settlement amount reached to 85.73, 49.75, 30.37, and 7.95 ng·g^-1 at 100 m from the road. The fluctuation type, including Benzo[k]fluoranthene, Indeno [1,2,3-cd]pyrene, Benzo[a]anthracene and Chrysene, had two settlement peaks at the 20th meters and 100th meters. The ΣPAHs content of orchard covering with grass reduced by 48.04% compared with normal roadside apple orchards. Phenanthrene and Fluoranthene concentration were in risk assessment values, and existed ecological risk.

Key words: road, apple orchard, soil, PAHs, exhaust pollution, HPLC, risk assessment