在北黄海中部泥质区采集柱状沉积物样品,对多环芳烃(PAHs)和黑碳(BC)的含量和来源进行研究。结果表明:(1)PAHs的含量变化范围为207~611ng/g;BC的含量变化范围为0.560~1.32mg/g;(2)对比低分子量(LMW)和高分子量(HMW)PAHs含量的历史变化趋势,发现1980s之前的PAHs主要来自于生物质的低温燃烧,之后主要来自于化石燃料的高温热解;(3)1920s之前,PAHs与BC含量基本保持稳定且处于较低值。1920s-1980s,PAHs含量受工业化和煤炭发展的影响较大,开始出现增长趋势。1980—1990s,由于能源消耗量的大幅度增加,导致PAHs和BC的含量迅速升高并达到最大值(1996年)。1990s初期-2000s初期,由于清洁能源的使用等原因,PAHs与BC含量都开始下降。(4)对PAHs和BC含量进行Spearman相关性分析,得出在1920年之前和1920—1980年之间,BC和PAHs含量无显著性相关(r=-0.25,P〉0.05,n=34;r=0.06,P〉0.06,n=11);而1980年之后,BC和PAHs含量呈显著性相关(r=0.90,P=0.04,72—5)。
Concentrations and sources of polycyclic aromatic hydrocarbons (PAHs) and black carbon (BC) were investigated based on a sediment core collected in the mud area of the central northern Yellow Sea. Results showed that: (1) The concentration of PAHs were in the value of 207 to 611 ng/g,and the values for BC were 0. 560 to 1.32 mg/g. (2)The comparison of low-molecular-weighted(LMW) and high-molecular-weighed (HMW) PAHs indicated that biomass burning with relatively low temperature was their main source prior to 1980s,and shifted to fossil fuels with higher combustion temperature after 1980s. (3) Before 1920s,the concentration of PAHs and BC remained in stable and lower levels. In 1920s-1980s,PAHs concentrations began to increase which could be large ly contributed to the rapid industrialization and coal usage in adjacent areas. After 1980s, the increase of energy consumption and vehicle population account for the continued increase of PAHs and BC concentrations, which reached to their maximum values about 1996,But the use of clean energy made them decreased since 1990s. (4) Before 1920s and 1920s-1980s, there are no correlation between PAHs and BC (r=- 0.25, P〉0.05 ,n= 34; r= 0.06,P〉0.06,n=11). After 1980,there is a strong association of PAHs and BC (r=0.90,P=0.04,n=5).