汕头红树林湿地表层沉积物环境因子对PAHs分布的影响

Effects of physical-chemical properties on distribution of polycyclic aromatic hydrocarbons in surface sediment of Shantou mangrove wetlands

为了探明红树林湿地表层沉积物环境因子对多环芳烃分布的影响,野外采集了汕头红树林湿地表层沉积物样品,实验室内有机溶剂提取、氧化铝硅胶柱净化和气质联用分析了沉积物多环芳烃的质量分数、CHN元素仪分析了沉积物有机碳和黑碳的质量分数、激光粒度仪分析了沉积物的粒级组成,研究了沉积物有机碳、黑碳和粒度等各环境因子与多环芳烃的相关性。结果表明:有机碳与2～3环、4环和总多环芳烃的质量分数显著相关(P<0.05),表明表层沉积物有机碳的质量分数对PAHs的分布产生了显著的影响;黑碳与2～3环、4环、5～6环和总多环芳烃的质量分数显著相关(P<0.01),表明表层沉积物黑碳的质量分数对PAHs的分布产生了显著的影响;粘粒与2～3环多环芳烃的质量分数显著相关(P<0.05),与4环、5～6环和总多环芳烃的质量分数显著相关(P<0.01),表明表层沉积物粘粒的质量分数对PAHs的分布也产生了显著的影响;多元线性逐步回归分析显示,各回归方程黑碳的偏回归系数值都是最大,沉积物黑碳的质量分数对多环芳烃的质量分数贡献最大,表明黑碳是多环芳烃分布的主要影响因素。

In order to find the effects of environmental factors on distributions of polycyclic aromatic hydrocarbons （PAHs） in man- grove sediments, PAH concentrations were determined using organic solvents, separated by aluminum oxide and silica gel column chromatography and analyzed by gas chromatography / mass spectroscopy （GC/MS） and organic carbon （OC） and black carbon （BC） were detected using CHN element instrument and grain size was tested using Particle Size Analyzer in surface sediment from three mangrove wetlands inside Shantou Wetland Demonstration Site, China. The correlations of PAHs with OC, BC and clay were stud- ied. Results showed that correlations of OC with 2-3 rings, 4 rings and total PAHs were significant （P〈0.05）, suggesting OC is a factor effected on distribution of PAHs; correlations of BC with 2-3 rings, 4 rings, 5-6 rings and total PAHs were significant （P〈0.01）; suggesting BC is a factor effected on distribution of PAHs; correlations of clay with 2-3 rings were significant （P〈0.05）, and correlations of clay with 4 rings, 5-6 rings and total PAHs were significant （P〈0.01）, suggesting clay is a factor effected on dis- tribution of PAHs. Further multiple linear stepwise regression analysis indicated that BC was the most important factor affected PAHs distribution in all physical-chemical properties of mangrove sediments.