上海城市不同绿地类型土壤重金属污染研究

2006年秋季对上海城市不同绿地类型土壤进行采样,其中包括居住区:华东师范大学一村草地类型(A);公园:上海植物园乔木类型(B、C)、灌木类型(D)、草地类型(E);学校:华东师范大学校区绿化乔木类型(F、G)、灌木类型(H)、草地类型(I);路旁绿地:浦东生态林乔木类型(J)、草地类型(K);废弃地:南汇老港垃圾填埋场乔木类型(L、M),草地类型(N)。共获得土壤样品42份。研究结果表明,上海城市各绿地类型的土壤受到了较强烈人为干扰,重金属污染现象普遍:绿地土壤中Cu、Zn、Pb、Cd的平均浓度分别为:39.84±17.37 mg·kg^-1,157.05±81.91 mg·kg^-1,41.33±23.14 mg·kg^-1,0.3425±0.1420 mg·kg^-1,居住区、公园、学校、路旁绿地、废弃地的内梅罗综合重金属污染指数分别为:2.4、2.8、2.6、1.9和1.5;同时还表明,不同绿地类型中土壤有其不同的污染方式:学校样地土壤重金属污染主要来自于交通因素,路旁绿化样地土壤的重金属来自于交通、客土等多方面因素共同作用,废弃地样地、公园样地和居住区样地土壤重金属污染则可能分别来自于固体废弃物、农林业活动和多种人类日常活动的共同作用。

A study on heavy metal pollution in different greenbelts types of Shanghai

In the autumn of 2006,a total of forty-two soil samples were collected from fourteen sampling sites,which belong to five different greenbelt types in Shanghai.They were grassland(A) in No.1 Estate of East China Normal University;woods(B,C),shrubbery(D) and grassland(E)in Shanghai Arboretum;woods(F,G),shrubbery(H) and grassland(I)in East China Normal University;woods(J)and grassland(K) in Pudong roadside greenbelt;woods(L,M) and grassland(N)in Laogang Landfill.The results revealed that soils of all the greenbelt types in Shanghai were disturbed intensively by human beings and generally polluted by heavy metals: the mean concentrations of Cu,Zn,Pb and Cd of the soil of all kinds of greenbelts were 39.84±17.37 mg·kg^-1,157.05±81.91 mg·kg^-1,41.33±23.14 mg·kg^-1,0.3425±0.1420 mg·kg^-1,respectively,with the composite pollution indexes of residential area,park,campus,roadside greenbelt and deserted land being 2.4,2.8,2.6,1.9 and 1.5,respectively.On the other hand,it also could be concluded that the way of pollution was variable in different greenbelt types: the main factor for heavy metal pollution of campus soil was vehicle,while the combination of both traffic and soil itself played a key role in the case of roadside greenbelt.On the contrary,the heavy metal pollution of deserted land,park and residential area was mainly caused by solid castoff,agricultural activities and the combination of different kinds of human beings daily behaviors.