红檵木叶片中富集PAHs节律变化特征

Rhythm characteristics of PAHs concentrations in the leaves of Loropetalum chinense

用气质联用仪对长沙市城市绿化常用的红檵木叶片中富集PAHs节律变化进行了研究。结果表明:红檵木叶片中在1月、4月、7月和10月的PAHs日均总含量之间差异性显著(P<0.05),日均含量分别为8.23、3.28、3.42和13.33mg/kg。叶片中PAHs组分在1月、4月、7月和10月的日变化也呈现出较大差异。其中中低环和高环PAHs含量之间差异显著(P<0.05)。红檵木叶片中总PAHs、中低环芳烃以及高环芳烃的存在显著的季节动态,全年含量平均值为7.53、7.07和0.46mg/kg,中低环芳烃年均占总量的95.08%,高环仅占4.92%。

PAHs consists of a number of toxic compounds which have great harmful effects on plants,anmials and human health.It has been commonly recognized that trees have great potential for the scavenging,storage and purification of relatively large a mounts of PAHs.The rhythm characteristics of enriched PAHs in vegetation leaves of Loropetalum chinense for a year were studied by GC-MS.The results show that the total content of PAHs daily in leaves of Redrlowered loropetalum had the difference significantly（P0.05） between January,April,July and October,daily average concentrations were 8.23,3.28,3.42 and 13.33 mg/kg,respectively.PAHs components in the leaves in January,April,July and October also showed a diurnal variation quite different.There were significant differences（P0.05） between 2～4 ring and 5～6 ring PAHs.Total PAHs,2～4 ring and 5～6 ring content in leaves of Loropetalum chinense had significant seasonal dynamics,year average content of their was 7.53,7.07 and 0.46 mg/kg,respectively.2～4 ring constituted 95.08% of the total annual,and 5～6 ring content only 4.92%.