长白山表层土壤中有机氯农药和多氯联苯的海拔高度分布特征

Elevational Gradients of Organochlorine Pesticides and Polychlorinated Biphenyls in Topsoils from Changbai Mountain

吉林省洁净地区长白山表层土壤中有机氯农药(OCPs)和多氯联苯(PCBs)总体上污染较轻,但高于一些其他地区。表层土壤的OCPs和PCBs表现出明显的随海拔高度增大的趋势,初步显示了高山冷凝捕集效应的影响。长白山旅游地区表层土壤受到轻微HCHs和DDTs的污染(平均值分别为12.4 ng/g和12.3 ng/g)。长白山附近较低海拔地区表层土壤中OCPs含量要略高一些,表明农业活动逐渐增大。HCHs和DDTs都未超过国家土壤环境质量标准的一级,但个别地点DDTs可能对鸟类和土壤生物具有一定的潜在生态风险。不排除在个别采样点有林丹和三氯杀螨醇被使用的可能性。长白山及附近地区表层土壤样品中∑7PCBs含量为7.3～31.9ng/g,平均17.2 ng/g。PCBs污染主要集中在海拔1450 m和1800 m处。7种PCBs异构体的含量依次为:PCB 28>PCB 52>PCB 180>PCB 138>PCB 101>PCB 153>PCB 118。

Topsoils from an uncontaminated area of Changbai Mountain of Jilin province were generally less polluted by the organochlorine pesticides（OCPs） and polychlorinated biphenyls（PCBs）,but it is more so than in other areas.The total concentrations of OCPs and PCBs in the topsoils showed a clear increasing trend with altitude,which can be interpreted as an Alpine condensation trap effect.Topsoil in the scenic spot of Changbai Mountain was slightly polluted by HCHs and DDTs（with each average value as of 12.4 ng/g and 12.3 ng/g respectively）.The lower altitude area near Changbai Mountain had slightly higher concentrations of OCPs and PCBs,which indicated that agricultural activity gradually increased.The concentrations of HCHs and DDTs have not exceeded the national soil and environmental quality standards level I,but DDTs in some individual locations may cause a certain potential ecological risks to birds and soil organisms.The possibility is that lindane and dicofol are used in some sampling points.The concentrations of PCBs in topsoil samples from Changbai Mountain and its vicinity were 7.3-31.9 ng/g,with an average value of 17.2 ng/g.PCB contaminated areas are mainly concentrated in places with an altitude of between 1450 m and 1800 m.7 kinds of PCBs can be ranged by concentrations as follows： PCB 28PCB 52PCB 180PCB 138PCB 101PCB 153PCB 118.