大亚湾海域多环芳烃和有机氯农药的高分辨率沉积记录

以GC／ECD和GC／MS内标法分析测定了大亚湾沉积物柱样（DYW03—8）中多环芳烃（PAHs）和有机氯农药（0CPs）的含量，结合^210Pb定年，重建了该海域近50年来PAHs和OCPs的污染历史，并对其可能的来源和输入途径进行了探讨。结果表明，近50年来该海域沉积物中PAHs和OCPs的含量总体上均呈上升趋势，且一般都在上世纪90年代以后这种上升变得更加明显；PAHs主要来源于化石燃料的不完全燃烧，即热成因，并可能主要通过大气颗粒物沉降以及工业和生活污水的直接排放等途径进入水体沉积物中；HCHs和DDTs的组成特征及其变化趋势揭示，该区可能曾大量使用过林丹（γ-HCHs）作为杀虫剂，近15年来随着该地区各种经济开发活动的加强，残留在土壤中的这些农药组分更多地随地表径流进入到水体沉积物中。同时，DDTs类农药也可能仍存在新的输入源，但这种输入的强度在近几年似乎有所减弱。

HIGH-RESOLUTION SEDIMENTARY RECORD OF PAHs AND OCPs IN DAYA BAY, CHINA

The concentrations of polycyclic aromatic hydrocarbons(PAHs) and organochlorine pesticides(OCPs) in the sediments of core DYW03-8 from the Daya Bay were measured based on GC/MS and GC/ECD standard addition methods.Combining the ~(210)Pb dating,fifty-year pollution history of PAHs and OCPs in this sea area was reconstructed and their possible sources and transport pathways were also discussed.In general,the concentrations of PAHs and OCPs in the sediments have shown rising trends since 1949,especially since(1990's).The pyrolysis-derived contamination was a significant source of PAHs,which was mainly carried into the sea by atmospheric deposition and discharge of industrial and domestic sewage.The compositional characteristics of HCHs and DDTs indicated that Lindane might have ever been used in large quantities as a pesticide in this area,and more and more residual pesticides in soils might have been carried into the sea by land runoff with intensified economic developing activities in recent 15 years.In the mean time,there may exist some new sources of DDTs,but the inputing amount seems to have been reduced in recent 5 years.