【作者】 韩志刚；

【导师】 杨玉盛； 倪进治；

【作者基本信息】 福建师范大学 ， 环境工程， 2009， 硕士

【摘要】 本文开展了以下三个方面的研究工作:（1）调查了福州市区周边农业土壤中多环芳烃（PAHs）的污染状况,并对其来源进行了解析;（2）研究了菲（Phe）和芘（Pyr）在土壤中的老化现象及其在土壤不同粒径组分中的分配特征:（3）通过土柱淋溶实验,研究了淹水状态下不同浓度的溶解性有机质（DOM）对土壤中Phe和Pyr迁移行为的影响。主要结果如下:（1）通过调查福州市农业表层土壤（0-10 cm）中美国环境保护署优控的16种PAHs含量,并对其来源和生态风险进行了分析。结果发现,供试土样中16种PAHs检出率达到100%,其总量范围为100.2～1 215.1μg·kg^-1。土壤中PAHs主要源于生物燃烧和石油。供试土样中PAHs的总Bap_eq值有50%超过荷兰规定的目标值,并且86%的超标土样是由于苯并[a]芘的Bap_eq值超过目标值所致。因此,福州市部分农业土壤存在一定的潜在的生态风险。（2）研究了Phe和Pyr在水稻土中的老化及其在土壤不同粒径组分（粘粒、细粉粒、粗粉粒、细砂粒和粗砂粒）中的分配特征。结果表明,随着时间的推移,土壤中Phe和Pyr相对提取率逐渐降低。老化90天时,土壤不同粒径组分中Phe和Pyr的量占整个土壤中Phe和Pyr总量百分比的大小顺序分别为细砂粒＞粗粉粒＞细粉粒＞粗砂粒＞粘粒和细粉粒＞细砂粒＞粗粉粒＞粘粒＞粗砂粒。（3）采用人工填装土柱淋溶实验研究了淹水状态下不同浓度的DOM溶液对Phe和Pyr在土壤中迁移行为的影响。实验结果表明,淹水状态下DOC浓度分别为0、17.2 mg·kg^-1、51.5 mg·kg^-1和694.8 mg·kg^-1的超纯水、DOM1、DOM2和DOM3溶液都能促进Phe和Pyr在土壤剖面中的迁移,并且DOC浓度越高,DOM对Phe和Pyr在土壤中迁移行为的影响越明显。此外,DOM对Phe在土壤中迁移的影响要明显高于Pvr。更多还原

【Abstract】 In order to understand the fate and behavior of aging and transporting of PAHs in soil,several experiments were designed in this study.The pollution status and sources of PAHs in agricultural surface soils of Fuzhou City were investigated.Aging of spiked phenanthrene（Phe） and pyrene（Pyr） in paddy soil and the distributions of Phe and Pyr in different particle-size fractions of soil were studied.Vertical transport of Phe and Pyr under flooded conditions was investigated by simulations experiments in soil columns. The following are the main results in this study.（1） The contents of 16 USEPA priority PAHs in agricultural surface soils（0-10 cm） were studied,and the sources and ecological risks of PAHs were also analyzed.Results demonstrated that 16 PAHs were detected in all soil samples.The concentrations of the sum of 16 PAHs in agricultural soils ranged from 100.2μg·kg^-1to 1 215.1μg·kg^-1.The main sources of PAHs in agricultural soils were from petroleum and biomass burning. Toxicity equivalency factor（TEF） was used to convert the toxicity value of individual PAHs to an equivalent toxicity value of benzo[a]pyrene(Bap_eq).Total Bap_eq values of the agricultural soils ranged from 2.50μg·kg^-1 to 147.95μg·kg^-1 and half of them were greater than Dutch target value(total Bap_eq=32.96μg·kg^-1).The results in this study demonstrated that,to some extent,some areas of agricultural soils in Fuzhou city had potentially ecological risks.（2） Aging of spiked Phe and Pyr in paddy soil and the distributions characteristics of Phe and Pyr in different particle-size fractions（clay,fine silt,coarse silt,fine sand and coarse sand） of soil were studied.The results showed that the relative extractability of Phe and Pyr were gradually reduced with aging time.After 90-day aging,the percentage of the amount of Phe in different particle-size separate to the total amount of Phe in bulk soils decreased in the order of fine sand＞coarse sand＞fine silt＞coarse silt＞clay.The percentage of the amount of Pyr in different particle-size separates to the total amount of Pyr in bulk soils decreased in the order of fine silt＞fine sand＞coarse silt＞clay＞coarse sand.（3） Vertical transport of Phe and Pyr under flooded conditions was investigated by simulations experiments.The results showed that ultrapure water(DOC,0mg·kg^-1), DOM1(DOC,17.2mg·kg^-1),DOM2(DOC,51.5mg·kg^-1) and DOM3(DOC,694.8 mg·kg^-1) may increase transport of phenanthrene and pyrene in flooded soil columns,and the transport of phenanthrene and pyrene was deeper with increased concentration of DOC,and the transport of phenanthrene was shown to be more facilitated than pyrene.更多还原