多环芳烃在珠江口的百年沉积记录  

Over One Hundred Year Sedimentary Record of Polycyclic Aromatic Hydrocarbons in the Pearl River Estuary, South China

作　　者：刘国卿[1] 张干[1] 李军[1] 李可昌[1] 郭玲利[1] 刘向[1] 池继松[2] 彭先芝[1] 祁士华[3] 

机构地区：[1]中国科学院广州地球化学研究所有机地球化学国家重点实验室,广州510640 [2]中国科学院南海海洋研究所,广州510301 [3]中国地质大学(武汉)环境学院,武汉430074

出　　处：《环境科学》2005年第3期141-145,共5页Environmental Science

基　　金：国家重点基础研究发展规划 (973 )项目 (2 0 0 3CB415 0 0 2 ) ;中国科学院基金项目 (ZKCX 2 2 12 )

摘　　要：伶仃洋西滩为珠江口的重要沉积区之一.本文分析了采自伶仃洋西滩沉积钻孔(Core 2 5 )中多环芳烃的垂直分布和含量特征,结合2 1 0 Pb定年,重现了该地区近百年来多环芳烃(PAH)的沉积历史.多环芳烃在整个沉积剖面(0～6 2cm)的含量介于5 9～330ng·g-1 (干重) .从1 9世纪6 0年代开始,PAH沉积通量逐渐上升,在2 0世纪5 0年代达到第一个高峰值.PAH含量在2 0世纪6 0～70年代有所降低.2 0世纪80年代后,PAH含量急剧上升,并在90年代达到最高值.珠江口沉积柱中的多环芳烃主要为热成因来源,其通量变化与周边人类活动(国内生产总值,机动车数量,能源消耗)呈正相关.大气干湿沉降及地表的冲刷作用是PAH进入水体沉积物的主要途径.The western shoal of the Lingding Bay is known to be an important deposition zone of terrestrial substance in the Pearl River Estuary (PRE). In this study, the vertical variations of concentration and fluxes of polycyclic aromatic hydrocarbon (PAH) are investigated in a core from the west shoal of Lingding Bay. In combining with 210Pb-dating, the PAHs sedimentary record in the last 100 years is reconstructed. The ∑PAH concentration ranged from 59 ng·g -1 to 330 ng·g -1 throughout the core with two distinct peaks. An initial increase in ∑PAH concentration was found around the 1860s, followed with the first maximum in the 1950s. There was a decrease in total PAHs concentration and flux in 1960s and 1970s. A sharp increase in PAHs levels was observed from 1980s and a maximum was found in the 1990s. PAHs diagnostic ratios indicate that PAH in the sediment core are mainly of pyrolytic origin. PAHs concentrations are found to correlate positively with the Gross Domestic Production, vehicle numbers and power generation in the surrounding regions, indicating that the PAHs in the sediment core are mainly anthropogenic. Atmospheric deposition and land runoff may serve as the important pathway of PAHs input to the sediment.

关 键 词：多环芳烃 沉积钻孔 珠江口 沉积通量 垂直变化 

分 类 号：X53[环境科学与工程—环境工程]