通过测定汾河上中游流域13个点位丰水期和枯水期水体、表层沉积物中PAHs浓度,分析其分布特征及影响因素.结果表明:汾河上中游流域丰水期和枯水期水中PAHs的平均浓度分别为0.365 μg·L-1和0.835 μg·L-1,枯水期PAHs总体高于丰水期;丰水期和枯水期沉积物中PAHs平均浓度分别为1444 μg· kg-1和2407 μg·kg-1,枯水期PAHs总体高于丰水期;水和沉积物中PAHs的组成主要是2～4环,但沉积物中高环PAHs组成显著高于水中;丰水期和枯水期巾游段(寨上到南关)水体和沉积物中PAHs浓度整体均高于上游段(雷鸣寺到汾河水库).丰水期和枯水期沉积相-水相分配系数Kp值分别为642～32345 L·kg-1和671～44929 L·kg-1,且随PAHs环数变大Kp值增大;丰水期和枯水期沉积相-水相实测的有机碳归一化分配系数(lgKoc)总体高于预测值上限;丰水期和枯水期lgKoc与lgKow.均呈较好的相关性,可决系数(R2)分别为0.764、0.725,枯水期斜率大于丰水期斜率,枯水期较丰水期沉积物吸附的PAHs更多.Kp值与有机碳/CODCr比值Kod呈正相关,可决系数(R2)分别为0.625和0.728,丰水期和枯水期PAHs Kp值受沉积物中有机碳含量和水中CODCr含量的影响.“,”The distribution and major components of polycyclic aromatic hydrocarbons (PAHs) were studied in upper middle of the Fen River basin,China.Water and surficial sediment samples collected from 13 sites during both flood and dry seasons were analyzed.It was observed that the PAHs concentration in dry season was higher than that in flood season in both water and surficial sediment,with 0.835 pg·L-1 and 0.365 μg· L-1 in the water samples,and 2407 μg· kg-1 and 1444 μg·kg 1 in the surficial sediment samples,respectively.The major components were PAHs with 2 ～ 4 rings in both samples and the concentration of multiple rings PAH was significantly higher in surficial sediment samples than that in water samples.The concentration of PAHs in both samples at the middle section (from the Walled to the SouthGate) was significantly higher than those at the upper section (from the Thunder temple to the Fenhe Reservoir).The Kp values of sedimentary-water partition coefficients,during the flood and dry season,were 642 ～ 32345 L· kg-1 and 671～44929 L·kg-1,respectively,and increased with the ring number of PAHs.The organic carbon normalized partition coefficient (lgKoe.) is higher than expected.The correlation coefficients (R2) of lgKoc and lgKow in the flood and dry season were 0.764 and 0.725,respectively,while the slope of lgKoc and lgKow dry season was greater than that of flood season,the same for the absorption of PAHs by surficial sediments.The Kp value showed positive correlation with the Kod(organic carbon in surficail sediments/CODcr in water),with the correlation coefficients (R2) 0.625 and 0.728 in flood and dry seasons,respectively,indicating that the Kp of PAHs is influenced by both the organic carbon in surface sediments and the CODCr in water.