【摘要】 采集了汕头国际湿地核心区红树林表层沉积物上层(0~10cm)和下层(10~20cm)样品,用超声溶剂萃取和GC-MS法分析了沉积物中的多环芳烃(polycyclic aromatic hydrocarbons,PAHs)、有机碳、黑碳和粒径的组成。结果显示,沉积物上、下层均以4环PAHs的含量最高,不同环数PAHs表现为中环数含量较高,低环和高环含量较低;上层∑PAHs含量明显大于下层,同时沉积物上层∑PAHs含量、有机碳和黑碳及粘粒、粉砂的质量分数均高于下层;pH没有变化。相关性分析显示,沉积物上、下层中的有机碳与∑PAHs含量无相关关系,黑碳、∑PAHs含量和粉砂表现为两两显著相关,表明沉积物中粉砂是影响PAHs在沉积物中行为和归宿的重要因素,而黑碳是形成分层效应的根本影响因素。更多还原

【Abstract】 Sediment samples at 0-10 cm and 10-20 cm depths were collected from Shantou mangrove wetland,and their particle sizes and the contents of polycyclic aromatic hydrocarbons(PAHs),organic carbon,and black carbon were determined by the methods of ultrasonic solvent extraction and GC-MS.The two sediment layers were dominated by 4-ring PAHs,followed by moderate molecular weight PAHs,and lower or molecular weight PAHs.The contents of PAHs,organic carbon,and black carbon,and the percentages of silt and clay were higher in 0-10 cm than in 10-20 cm layer,but the pH value had no difference between the two layers.Correlation analysis showed that in the two layers,PAHs content had no correlation with organic carbon content but significantly correlated with black carbon content(P<0.01),and significant correlations were observed among the contents of silt,black carbon,and PAHs(P<0.05),suggesting that silt content was the main factor affecting the PAHs distribution in Shantou mangrove sediments,and black carbon could be the essential factor for the stratification of PAHs in different sediment layers.更多还原