厦门海域正构烷烃组成特征及石油烃污染情况研究

The characteristic parameters of N-alkanes and petroleum pollution of Xiamen bay

本文对厦门海域水体及表层沉积物的正构烷烃含量及水体中的石油烃含量进行检测,通过正构烷烃的组成特征和特征比值分析其来源,并对石油烃污染情况进行评价。结果表明,厦门海域水体中石油烃含量符合国家一类海水水质标准,正构烷烃含量与1995年厦门海域的水体正构烷烃含量相比有较明显的升高,石油烃污染有加重的可能性。沉积物正构烷烃含量为1.80~4.27μg/g,对姥鲛烷和植烷比值(Pr/Ph)、长短链比值(L/H)、碳优势指数(CPI)和主峰碳数等特征比值的分析,表明厦门海域沉积物环境为还原性,厦门西海域、同安湾和九龙江口海域正构烷烃组成为双峰型,陆源贡献大于海洋贡献且有受到石油烃污染的可能性;东海域和大嶝海域正构烷烃组成表现为单峰型,主要体现为海洋生物贡献,但是无法排除石油烃污染的可能性。

The concentration and composition characteristics of n-alkanes in seawater and sediment of Xiamen bay were detected to elucidate their sources and the condition of petroleum pollution.The concentration of oil in seawater conformed to the first class of seawater quality standards.The concentrations of n-alkanes were higher than those in 1995 indicating the increased risk of petroleum pollution in seawater.The concentrations of n-alkanes in sediments were ranged from 1.80 μg/g to 4.27 μg/g.The characteristic parameters of Pr/Ph,L/H,CPI dominant peaks and so on suggested the sediments in Xiamen bay were reducible.Furthermore,the n-alkanes in Tong＇an bay,western Xiamen and Jiulong estuary were double perk-clustered,mainly from terrestrial sources and the sediments in these areas might be contaminated by petroleum while that in eastern Xiamen and Dadeng were one perk-clustered,mainly from marine organisms but could not exclude the possibility of petroleum pollution.