Does the Distribution of Polycyclic Aromatic Hydrocarbons in Soil Particle-Size Separates Affect Their Dissipation during Phytoremediation of Contaminated Soils?

摘要

This study was conducted to determine the relationship between the distribution patterns of polycyclic aromatic hydrocarbons (PAHs) in particle-size separates and their dissipation during phytoremediation of urban contaminated soils.The results showed that the percentage of total PAHs removed from soils ranged from 28.0％ to 45.6％,with an average value of 36.8％ in three-month pot experiments.The percentage of total PAHs removed from initial soils during phytoremediation had a positive correlation with the percentage of total PAHs in coarse sand fraction (r=0.813,p＜0.10) and had a significantly negative correlation with the percentage in frne silt fraction (r=0.898,p＜0.05) of initial soils.The results indicated that the bioavailability of PAHs in soil particle-separates might be affected by the quality of soil organic matter they were associated with and PAHs in the sand fraction were more bioavailable than those in silt and clay fractions.