Lu Zhi-qiang, Zheng Wen-jiao, Ma Li
School of Life Sciences, Research Centre for Wetland and Ecological Engineering, Xiamen University, Xiamen 361005, China.
J Environ Sci (China). 2005;17(2):285-9.
The polycyclic aromatic hydrocarbons(PAHs) concentrations were determined in the root of three mangrove species (Kandelia candel, Avicennia marina and Bruguiera gymnorrhiza) and their growing environment (sediment) in mangrove wetlands of Jiulong River Estuary, Fujian, China. The total PAHs (16 parent PAHs) in mangrove sediments ranged from 193.44 to 270.53 ng/g dw, with a mean value of 231.76 +/- 31.78 ng/g dw. Compared with other mangrove and coastal marine sediments, the PAHs concentrations of all the sampling areas in this study were at relatively lower level. The total PAHs (13 parent PAHs) values varied from 30.83 to 62.73 ng/g dw in mangrove roots. Benzo[a]pyrene(five-ring), fluoranthene(four-ring) and pyrene(four-ring) dominated in mangrove sediments. Based on ratios of phenathrene/anthracene, fluoranthene/pyrene and fluoranthene/pyrene + fluoranthene, the main possible sources of surface sediment PAHs were identified as grass, wood or coal combustion for mangrove wetlands of Jiulong River Estuary. Naphthalene(two-ring) and phenathrene(three-ring) were the most abundant compounds in mangrove roots. Sediment-to-vegetation bioconcentration factors (BCF(SV) S) were calculated and their relationships with PAHs' physico-chemical properties were investigated. The average BCF(SV) S of PAHs for three mangrove species roots were almost all under the level of 1 except for naphthalene. Good linear relationship between BCF(SV) values for mangrove roots and PAHs water solubility, octanol-water partitioning coefficients was derived in present study. The solubility and the octanol-water partition coefficient were proved to be good predictors for the accumulation of PAHs in mangrove roots, respectively.
在中国福建九龙江口红树林湿地，测定了三种红树植物（秋茄、白骨壤和木榄）的根系及其生长环境（沉积物）中多环芳烃（PAHs）的浓度。红树林沉积物中总PAHs（16种母体PAHs）含量在193.44至270.53 ng/g干重之间，平均值为231.76±31.78 ng/g干重。与其他红树林和沿海海洋沉积物相比，本研究中所有采样区域的PAHs浓度处于相对较低水平。红树林根系中总PAHs（13种母体PAHs）含量在30.83至62.73 ng/g干重之间。苯并[a]芘（五环）、荧蒽（四环）和芘（四环）在红树林沉积物中占主导地位。根据菲/蒽、荧蒽/芘和荧蒽/芘+荧蒽的比值，确定九龙江口红树林湿地表层沉积物PAHs的主要可能来源为草、木材或煤炭燃烧。萘（二环）和菲（三环）是红树林根系中含量最丰富的化合物。计算了沉积物-植被生物富集系数（BCF(SV)S），并研究了它们与PAHs理化性质的关系。除萘外，三种红树植物根系PAHs的平均BCF(SV)S几乎都低于1。本研究得出红树林根系BCF(SV)值与PAHs水溶性、正辛醇-水分配系数之间具有良好的线性关系。结果表明，溶解度和正辛醇-水分配系数分别是PAHs在红树林根系中积累的良好预测指标。
