State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Xianlin Avenue 163, 210023 Nanjing, China.
Fujian Provincial Academy of Environmental Science, No.10, Huan Bei San Cun, Fuzhou 350013, China.
Chemosphere. 2016 Feb;145:431-7. doi: 10.1016/j.chemosphere.2015.11.106. Epub 2015 Dec 13.
Little is known about the effects of biochar on the fate and behavior of micropollutants in soil, especially in the presence of soil macrofauna. Using a 14C-tracer, we studied the fate of 2,4-dichlorophenol and phenanthrene, after 30 days in soil in the presence of a biochar (0-5%, dry weight) produced from China fir at 400 °C and/or the earthworm Metaphire guillelmi. Application of the biochar significantly reduced the degradation and mineralization of both pollutants and strongly increased the accumulation of their metabolites in soil. The earthworm had no significant effects on the degradation of parent molecules of the pollutants but it significantly reduced the mineralization of the pollutants independent of the presence of the biochar. Although at an application rate of <1% the biochar strongly sorbed both pollutants, it did not significantly decrease the bioaccumulation of free dichlorophenol and phenanthrene and their metabolites by the earthworm. Our results demonstrate the complex effects of biochar on the fate, transformation, and earthworm bioaccumulation of organic pollutants in soil. They show that biochar application may not be an appropriate strategy for treating soil contaminated with hydrophobic organic pollutants and underline the importance of soil-feeding earthworms in risk assessments of biochar effects on soil remediation.
关于生物炭对土壤中微污染物的命运和行为的影响，人们知之甚少，特别是在存在土壤大型动物的情况下。我们使用 14C 示踪剂，研究了在存在由 400°C 下生产的中国枞木制成的生物炭（0-5％，干重）和/或蚯蚓 Metaphire guillelmi 的情况下，2,4-二氯苯酚和菲在土壤中 30 天后的命运。生物炭的应用显著降低了两种污染物的降解和矿化作用，并强烈增加了它们在土壤中的代谢物的积累。蚯蚓对污染物母体分子的降解没有显著影响，但无论是否存在生物炭，它都显著降低了污染物的矿化作用。尽管生物炭的应用率<1％，但它强烈吸附了这两种污染物，但它并没有显著降低蚯蚓对游离二氯苯酚和菲及其代谢物的生物累积。我们的结果表明，生物炭对土壤中有机污染物的命运、转化和蚯蚓生物累积有复杂的影响。它们表明，生物炭的应用可能不是处理受疏水性有机污染物污染的土壤的合适策略，并强调了土壤食性蚯蚓在生物炭对土壤修复影响的风险评估中的重要性。
