不同玉米品种Cd、Pb、Zn和As积累与转运特性  

Accumulation and Transport Characteristics of Cd,Pb,Zn,and As in Different Maize Varieties

作　　者：任超 肖建辉 李竞天 杜倩倩 朱利文 王浩 朱瑞祯 赵海洋 REN Chao;XIAO Jian-hui;LI Jing-tian;DU Qian-qian;ZHU Li-wen;WANG Hao;ZHU Rui-zhen;ZHAO Hai-yang(No.1 Institute of Geological and Mineral Resources Survey,Henan Bureau of Geoexploration and Mineral Development,Luoyang 471000,China;Key Laboratory of Au-Ag-Polymetallic Deposit Series and Deep-seated Metallogenic Prognosis of Henan Province,Luoyang 471000,China)

机构地区：[1]河南省地质矿产勘查开发局第一地质矿产调查院,洛阳471000 [2]河南省金银多金属成矿系列与深部预测重点实验室,洛阳471000

出　　处：《环境科学》2022年第8期4232-4252,共21页Environmental Science

基　　金：中央土壤污染防治专项(2110402-农村环境保护)。

摘　　要：通过田间试验,研究了22个玉米品种同时在未污染、轻度、中度和重度重金属Cd、Pb、Zn和As复合污染农田土壤条件下,玉米植株各部位对Cd、Pb、Zn和As的富集和转运特性,并对Cd、Hg、As、Pb、Cr、Cu、Ni和Zn这8种重金属元素进行了主成分分析和相关性分析,探讨了玉米植株吸收Cd、Pb、Zn和As含量与土壤中重金属元素形态含量的关系.结果表明:(1)玉米植株不同部位Cd和Zn含量分布规律为:穗上茎叶>穗下茎叶>根>籽粒,Pb分布规律为:根>穗下茎叶>穗上茎叶>籽粒,As分布规律为:根>穗上茎叶>穗下茎叶>籽粒,分布规律的不同与作物本身积累特性以及研究区土壤中Cd、Pb、Zn和As的环境活性高低密切相关.(2)22个玉米品种遗传背景的较大差异造成品种间Cd和Pb的积累具有显著差异(P<0.05),表现为4种趋势:Cd和Pb复合高积累品种,单一Cd或Pb低积累品种(低Cd高Pb、低Pb高Cd),Cd和Pb复合低积累品种.其中3个品种籽粒Cd含量超过国家食品安全标准,14个品种茎叶Cd含量超过国家饲料卫生标准;所有品种茎叶和籽粒Pb含量均未超标,但部分品种籽粒Pb含量接近限值具有超标风险;不同玉米品种茎叶和籽粒As含量均远低于标准限值,表现出稳定的低积累特性;不同玉米品种茎叶Zn含量随土壤Zn含量的升高而升高,但籽粒Zn含量维持在满足植株正常生长的阈值范围内.(3)研究区玉米植株中Cd、Pb、Zn和As具有一定的同源性,主要受土壤中Cd、Pb、Zn和As污染物含量超标的影响较为深刻,这说明矿山采选和尾矿堆存带来的人为来源,玉米植株中Cu元素受到一定人为污染来源的影响,但影响程度有限;玉米植株中Hg、Ni和Cr元素间具有一定的同源性,说明成土母质和风化产物累积的自然来源.(4)玉米植株各部位Cd、Pb、Zn和As元素含量,以及Cr和Ni元素含量均具有极显著正相关性(P<0.01),Cd、Pb、Zn和As元素在植物体内的运输机制可能有�The enrichment and translocation characteristics of Cd,Pb,Zn,and As by various parts of maize plants were investigated using field experiments in 22 maize varieties simultaneously under uncontaminated,low,middle,and serious heavy metal Cd,Pb,Zn,and As complex-contaminated farmland soil conditions.The relationship between the uptake of Cd,Pb,Zn,and As by maize plants and the morphological content of heavy metals in the soil was also discussed through principal component analysis and correlation analysis of the concentrations of eight heavy metals,including Cd,Hg,As,Pb,Cr,Cu,Ni,and Zn.The results showed that:(1)the distribution pattern of Cd and Zn contents in different parts of the maize plant was as follows:upper stalk>lower stalk>root>seed,the distribution pattern of Pb was As follows:root>lower stalk>upper stalk>seed,and the As distribution pattern was:root>upper stalk>lower stalk>seed.The different distribution patterns were closely related to the accumulation characteristics of the crop itself and the environmental activity of Cd,Pb,Zn,and As in the soil of the study area.(2)There were significant differences in Cd and Pb accumulation among 22 maize cultivars due to their genetic background(P<0.05),which showed four trends:Cd and Pb compound high-accumulation varieties,single Cd or Pb low-accumulation varieties(low Cd and high Pb,low Pb and high Cd),and Cd and Pb compound low-accumulation varieties.Among them,the content of Cd in the grain of the three varieties exceeded the national food safety standard,and the content of Cd in the stem and leaf of 14 varieties exceeded the national food health standard.The Pb content in stems,leaves,and grains of all cultivars did not exceed the standard,but the Pb content in grains of some cultivars was close to the limit and had the risk of exceeding the standard.The content of As in the stem,leaf,and grain of different maize varieties was much lower than the standard limit value,showing a stable low-accumulation characteristic.The content of Zn in the stem and leaf of di

关 键 词：玉米 重金属复合污染 低积累 富集转运 协同效应 环境活性 

分 类 号：X171.5[环境科学与工程—环境科学] X53