安徽中北部河流沉积物的特征与多环芳烃分布

通过对安徽省中北部6条河流沉积物样品的粒径、矿物组分和有机质含量的测试,并应用气相色谱质谱联用仪测定了样品中萘、二氢苊、苊、芴、菲、蒽、荧蒽、芘、苯并a]蒽、、苯并a]芘和二苯并a,h]蒽等12种多环芳烃的含量,分析了研究区河流沉积物的特征和多环芳烃分布。研究结果表明:位于安徽省中北部的淮河南北岸支流沉积物粒径和矿物组分具有不同特征;就PAHs总量来看,北岸支流平均值为313.3ng/g,南岸支流平均为112.8ng/g,差异比较明显,南岸支流沉积物中大多数多环芳烃的平均含量都低于北岸支流(蒽和菲除外,二苯并a,h]蒽未检出);而有机质的含量,南北岸支流总体无明显差异(含量在0.55%至1.83%之间),但单条河流的分布呈沿水流方向自中上游至下游逐渐降低。

Sedimentary Characteristics and PAHs Distribution in Sediments from the Rivers in North Central Part of Anhui,China

Based on the experimental research of sedimentary samples from six rivers in north central part of Anhui Province,the sedimentary characteristics were obtained,such as grain size,clay mineral and organic matter.And the contents of polycyclic aromatic hydrocarbons(PAHs)including naphthalene,acenaphthylene,acenaphthene,fluorene,phenanthrene,anthracene,fluoranthene,pyrene,benz a]anthracene,chrysene,benzo a]pyrene and dibenzo a,h]anthracene,were determined by gas chromatography mass spectrometry(GC-MS).Made use of these data,sedimentary characteristics and PAHs distribution in sediments were analyzed.The results showed that average particle-size of the sediments from two southern branches are bigger than those from northern branches of Huaihe River.Clay minerals are mainly composed of kaolinite and montmorillonite in the sediments from northern branches.But in southern branches,the chlorite(Pihe River)or illite(Dongfeihe River)were found in sediment samples.Organic matter concentrations in the river sediments,except from Xifeihe River,are decreasing progressively to the lower reaches by controlling of sedimentary self-purification ability and carbonic consumption action in condition of pollution source decreasing.The great majority of PAHs content in sediment from the southern branches,especially Dongfeihe River,are lower than those from the northern branches.