黄河口及近海表层沉积物中烃类化合物的组成和分布

The distribution of hydrocarbons in the surface sediments from the Huanghe Estuary and adjacent area

为探讨黄河口近海表层沉积物有机质中烃类化合物的分布特征及输运过程,2003年9月采集了南北两个断面表层沉积物样品,对沉积物中正构烷烃和多环芳烃进行了分析,结果表明,黄河口表层沉积物中正构烷烃和多环芳烃的含量分别为0.38~2.55和0.371~0.650μg/g。在南北断面两种烃类化合物的分布明显不同：北断面受石油平台影响,烃类化合物在口门含量较高;南断面受黄河输入影响,由于大颗粒易于沉降,而吸附烃类化合物的能力较强的小颗粒易长距离输运,使这两种烃类化合物的含量从河口到近海整体呈上升的趋势。与北断面相比,南断面受水生源影响相对较弱,而且水生源的贡献随着离岸距离的增加而加强,在最大浑浊带后水生源急剧增强;在南断面多环芳烃主要来源为热解源,北断面多环芳烃受热解源和石油污染的共同影响。

The surface sediment samples from the Huanghe Estuary were collected in September 2003 to explore the distribution and transportation of hydrocarbons in organic matter.The total concentrations of alkanes and polycyclic hydrocarbons varied from 0.38~2.55 to 0.371 ~0.650 μg/g,respectively.Significant differences were observed between the northern section and the southern section.Owing to the influence of the oilfield near the Huanghe Delta,the levels of two kinds of hydrocarbons show the highest level at the mouth in the northern section.Owing to the influence of the water from the Huanghe River,the hydrocarbons increase with the increasing of the distance from the coast in the southern section because the larger size particles are easy to deposit at the mouth of the river and the smaller particles resided with more hydrocarbons are easy to transport over long distance.More biogenic n-alkanes were found in the northern section than that in the southern section.The farther away from the river,the less terrestrial organic matter was observed in the southern section.The PAHs mainly were originated from coal burning in the southern section,and PAH inputs could come from petroleum and coal burning in the northern section.