长江流域表层沉积物中多环芳烃分布特征及来源解析

Distribution and Sources of Polycyclic Aromatic Hydrocarbons in Surface Sediments from the Yangtze River

长江流域沉积物多环芳烃分析表明,多环芳烃浓度总和（不包括苝）约为10.31～1 239 ng·g-1,与国内外其他区域相比,整体处于一个低至中等程度的污染水平。长江自上游至下游,沉积物中多环芳烃含量呈上升趋势,与沿途各省多环芳烃的排放状况相吻合。扬州（YZ）和湘江（XJ）采样点沉积物中多环芳烃含量最高,污染最严重。根据多环芳烃的比值特征,长江流域沉积物中多环芳烃主要受以煤、木材、油类的燃烧影响较大,还有部分来自油类的泄漏,极少量来自自然成因。

Polycyclic aromatic hydrocarbons（PAHs） were determined in surface sediments from the Yangtze River basin. Total PAH concentrations（TPAH, perylene not included） varied from 10.31 ng·g-1to 1 239 ng·g-1, indicating a moderate to low level when compared with samples from the other regions worldwide. Concentrations of TPAH in sediments increased from the upper to the lower reaches, suggesting its emission along the Yangtze River. PAHs contents in sediments from the two highly polluted stations of YZ（Yangzhou） and XJ（Xiangjiang） were highest. According to the PAH ratio index calculations, these PAH molecules were primarily derived from petroleum combustion,biomass combustion and coal burning, followed by oil spillage, and the contribution of the direct input from nature origin was quite minor.