象山港海水和沉积物中多环芳烃分布特征和来源研究

本文研究了象山港多环芳烃（PAHs）在沉积物-海水中的分布特征，于2017年1月对港口9个采样点的沉积物和海水中16种优先控制PAHs进行分析，采用同分异构比值法和逸度方法进行来源分析和扩散行为研究。沉积物中PAHs范围为17.51×10–9～84.41×10–9，主要为高环PAHs，处于轻度污染等级。沉积物中多环芳烃主要来自高温燃烧源。表层水体、中层水体和底层水体中PAHs范围分别为41.78～105.72 ng/L、41.51～106.34 ng/L和9.18～145.17 ng/L，主要由低环PAHs组成。表层水体中PAHs主要来源于石油泄漏和石油燃烧。利用逸度系数判断PAHs扩散行为，萘（Nap）、苊（Ace）和芴（Flo）由沉积物向海水释放；苊烯（Acy）、菲（Phe）、蒽（Ant）和芘（Pyr）在沉积物和海水中处于动态平衡；荧蒽（Flu）、苯并a]蒽（BaA）、?（Chr）和苯并b]荧蒽（BbF）主要从海水向沉积物扩散并富集。

Distribution and sources of polycyclic aromatic hydrocarbons in seawater and sediment from Xiangshan port,China

In order to study the distribution of polycyclic aromatic hydrocarbons (PAHs) in the sediment-seawater system, 16 kinds priority control PAHs in the sediments and seawater from 9 sampling points at the Xiangshan port were analyzed in January 2017. The source analysis and diffusion equilibrium were conducted by isomerism ratio method and fugacity approach. The concentrations of PAHs in the sediments ranged from 17.51×10-9～84.41×10-9, mainly high ring PAHs, and the pollution level was minor polluted. The PAHs in the sediments primarily came from high temperature combustion sources. The ranges of PAHs in the surface seawater, intermediate seawater and bottom seawater were 41.78～105.72 ng/L, 41.51～106.34 ng/L and 9.18～145.17 ng/L, respectively, which low ring PAHs were the most abundant compounds. The sources of PAHs in seawater originated mainly from oil leakage and oil combustion. The fugacity fraction was calculated to judge the diffusion behavior of PAHs. Nap, Ace and Flo were released from sediments to seawater. Acy, Phe, Ant and Pyr were close to the dynamic equilibrium in sediments and seawater. Flu, BaA, Chr and BbF were mainly diffused from seawater to sediment.