不同功能区林下土壤多环芳烃分布特征及来源分析

以乌鲁木齐工业区、交通区、居民区和公园区的林带作为试验采样区,分别从各功能区林带土壤中多环芳烃(PAHs)的含量、组成、污染情况、来源4个方面,分析了土壤中16种PAHs污染特征。结果表明:乌鲁木齐不同功能区林下土壤平均PAHs的含量为(375.76±32.96)ng·g^-1,其中交通区>工业区>居民区>公园区。低环和高环PAHs含量分别占32.02%和67.98%。工业区林带和交通区林带土壤以4环和3环为主,居民区和公园区以5环为主。工业区和交通区林带土壤以轻度污染为主(42.90%和37.50%);而公园区和居民区以轻度污染(60.00%和66.67%)和未污染(40.00%和33.33%)为主。工业区林带土壤组分中占比最高和最低的分别是茚并(1,2,3-cd)芘(IcdP)占16.01%和?(Chr)占0.98%,交通区林带占比最高和最低的分别是荧蒽(Fla)占16.01%和苊(Ace)占0.49%,居民区林带分别是荧蒽(Fla)占15.66%和?(Chr)占0.21%,公园区林带分别是茚并(1,2,3-cd)芘(IcdP)占19.48%和?(Chr)占0.84%。以煤、木、草等生物质燃烧为污染源的样地最多的是公园区;以汽车尾气、石油燃烧为污染源的样地最多的是交通区。各功能区PAHs的来源主要为煤、生物质等的不完全燃烧。

Characteristics and sources of polycyclic aromatic hydrocarbons in soils under the forest belts from different functional zones

This study used the forest belt of Urumqi industrial,transport,living,and park functional zones as test sampling area.The pollution characteristics(content,composition,evaluation,and source)of polycyclic aromatic hydrocarbons(PAHs)in forest soils in the abovementioned functional zones were analyzed.The average total content of 16 PAHs in Urumqi was(375.76±32.96)ng·g^-1.The transport zone had the highest PAH content,followed by the industrial and living zones,and the park zone had the lowest PAH content.The PAH content in low and high cycles respectively accounted for 32.02%and 67.98%of the average content of the 16 PAHs.The forest belt of the industrial and transport zones was dominated by rings 4 and 3,respectively,and that of the living and park zones was dominated by ring 5.The soils in the forest belt of the industrial and transport zones were mildly polluted(42.90%and 37.5%,respectively),and those in the park and living zones were polluted(60.00%and 66.67%,respectively)and unpolluted(40.00%and 33.33%,respectively).In the industrial zone,the content of indene and(1,2,3-cd)pyrene was the highest(16.01%),whereas that of chrysene was the lowest(0.98%).Fluoranthene and acenaphthene had the highest and lowest contents in the transport zone,namely 16.01%and 0.49%,respectively.In the living zone,fluoranthene had the highest content(15.66%),and chrysene had the lowest(0.21%).Indene and(1,2,3-cd)pyrene had the highest content(19.48%)in the park zone,and chrysene had the lowest(0.84%).Most of the pollution in the park zone originated from the burning of coal,wood,grass,and other biomass.In the transport zone,most pollution was caused by automobile exhaust and petroleum combustion.Most of the PAH pollution in each functional zone came from incomplete combustion of coal and biomass.