锰化厂土壤重金属含量及景观植物吸收特征

目的]为Mn污染场地的植物修复提供理论依据。方法]调查锰化厂污染场地植物,分析场地植被物种组成、土壤和主要优势景观植物体内重金属含量。结果]锰化厂场地所记录的高等植物共有33种,隶属22科31属,优势种共有8种,分别为木薯、银合欢、类芦、鬼针草、金叶假连翘、马缨丹、水茄、杉木;土壤重金属Cu、Zn、Pb、Cd、Mn均不同程度的污染,与重金属污染场地土壤修复标准(DB43-T—1125—2016)相比,类芦土、金叶假连翘土、杉木土Mn含量均远超修复标准值,为标准限值的3.63~40.52倍,污染严重;5种景观优势植物中,杉木对Mn具有超富集能力,为Mn超富集植物,金叶假连翘对强酸性土壤适应性强,可应用于酸污染土壤修复。结论]在场地植物修复时,可根据土壤污染特征,合理配置植物,实现场地"修复+景观+经济效益"修复模式。

Heavy Metal Concentrations in Soils and Absorption Characteristics of Landscape Plants of Manganese Chemical Factory

Objective]The aim of the study was to provide the theory basis for landscape phytoremediation of heavy metal contaminated site.Method] The study surveyed plants species composition and growth status and analyzed heavy metal contents in soil and landscape dominant plants of manganese chemical factory,Guangdong.Result] There were 33 species plants belonging to 31 genera in 22 families,and the dominant species with a total of 8 kinds,were Manihot esculenta Crantz,Leucaena leucocephala (Lam.) de Wit,Neyraudia reynaudiana (kunth.) Keng,Bidens pilosa L.,Duranta erecta Linnaeus cv.Golden Leaves,Lantana camara L.,Solanum torvum Swartz,Cunninghamia lanceolata (Lamb.) Hook,respectively.Soil Cu,Zn,Pb,Cd and Mn were differently degree polluted,and Mn contents of Neyraudia reynaudiana (kunth.) Keng soil,Duranta erecta Linnaeus cv.Golden Leaves soil,and Cunninghamia lanceolata (Lamb.) Hook soil were more than repair standard for contaminated site by heavy metal (DB43-T-1125-2016),with ratio of 3.63 to 40.52 times,seriously polluted.Five landscape dominant plants,Cunninghamia lanceolata (Lamb.) Hook.could hyperaccumulate Mn,was Mn hyperaccumulation plant.Duranta erecta Linnaeus cv.Golden Leaves was strongly adapted to strongly acidic soil which pH was 2.58,could be applied to acid soil remediation.Conclusion]Contaminated site phytoremediation could rationally configurate plant according to soil pollution characters,in order to implement repair mode of repair,landscape and economic efficiency.