多数多环芳烃（PAHs）因其水溶性低，且易被土壤有机质固持，曾经被认为其迁移能力十分微弱。但土壤中溶解性有机质可能影响PAHs的溶解、吸附等环境过程，进而影响其迁移性。本文旨在研究富里酸提取的溶解性有机质（FDOM）对PAHs在土－水间迁移的影响及其可能机制。溶液化学稳定性研究结果显示，FDOM在溶液pH 2.0～7.0、CaCl2浓度0～1 500 mmol L-1范围内均能保持较好的分散性，未发生絮凝沉淀。室内土柱淋溶试验结果表明，FDOM在土壤中具有较强的迁移能力，在FDOM持续淋溶条件下，菲、芘以及苯并[a]芘在淋出液中的浓度明显提高，并有少量二苯并[a, h]蒽淋出。FDOM淋溶处理的土柱表层土壤中菲、芘、苯并[a]芘和二苯并[a, h]蒽的淋失率分别为92.06%、92.07%、84.52%和23.27%，显著高于对照组（p<0.05）。以上研究结果表明，FDOM可作为载体提高PAHs在土壤中的迁移性，增加PAHs向深层土壤和地下水迁移的可能性。
Batch experiment was performed to study effects of different aquatic factors (pH and iron intensity) on dispersibility of dissolved organic matter (DOM) extracted from Fulvic acid. It was found that the DOM extracted from fulvic acid (FDOM) remained high in dispersibility and did not precipate in solutions with pH between 2.0～7.0 and CaCl2 concentration between 0～1 500 mmol L-1 without precipitation. Column leaching experiments were conducted to investigate effect of FDOM on transport of polycyclic aromatic hydrocarbons (PAHs) in the soil. With continuous irrigation of FDOM, the concentrations of Phenanthrene (Phe), Pyrene (Pyr), and Benzo[a]pyrene (B[a]P) in leachate were significantly increased, and even a limited amount of Dibenzo (a, h) acenaphthene (DBA) was also detected in the leachate. After leaching, the leaching lost rate of Phe, Pyr, B[a]P and DBA in the surface soil was 92.06%, 92.07%, 84.52% and 23.27%, respectively. These findings indicated that FDOM could act as carrier facilitating PAHs transport in the soil, thus enhancing the possibility of PAHs moving deeper into the soil and ground water.
韦 婧,宋 静,黄玉娟,罗 飞,李春平,陈梦舫,骆永明.溶解性富里酸对土壤中多环芳烃迁移的影响[J].土壤学报,2013,50(2):230-236. DOI:10.11766/trxb201205200184 Wei Jing, Song Jing, Huang Yujuan, Luo Fei, Li Chunping, Chen Mengfang, Luo Yongming. Effect of dissolvable fulvic acid on transport of polycyclic aromatic hydrocarbons in soil[J]. Acta Pedologica Sinica,2013,50(2):230-236.复制