桑树对土壤重金属污染修复潜力研究

为探究桑树对土壤重金属污染的修复潜力，以工业区周边桑树及与之对应根基土壤样品为研究对象，通过测定土壤样品中Mn、Ni、Zn、Cd、Hg、Pb、As、Cu、Cr等9种重金属元素的含量，以内梅罗综合污染指数法对区域土壤重金属污染进行分级评价；通过主成分分析对区域土壤重金属污染来源进行解析，分析桑树中不同元素间的相互作用；通过计算桑树的富集、转运系数分析桑树对土壤重金属污染的修复潜力。结果表明：城郊工业区土壤中Mn、Ni、Pb元素处于清洁状态；Zn、Cd、As、Cr元素处于轻度污染水平；Hg元素处于重度污染水平。区域土壤重金属元素整体处于中度污染水平。通过主成分分析，Mn、Cr、As、Hg、Cd污染可能不同程度受燃煤、金属冶炼等因素影响；Pb、Ni可能来源于交通污染源以及成土母质双重影响；Cu可能与区域交通污染及有机肥施用有关。综合分析认为：桑树对Ni元素综合富集能力相比于其他元素较强，对Zn、Cd、Hg具有较强的转运能力，对Ni、Zn、Cd、Hg具有较强的修复潜力，其中对Ni元素的修复潜力最强。桑树可作为Ni、Zn、Cd、Hg复合污染地生态修复的首选树种。     

Pb、Cd复合污染对龙须草光合作用的影响

通过九组不同水平的重金属Pb、Cd复合污染土壤种植龙须草试验,以检测对龙须草光合作用的影响,检测龙须草对重金属复合污染的耐性,从而探讨龙须草修复重金属污染环境的能力。光合分析的结果表明：随着Pb、Cd复合污染含量的升高,龙须草的光合综合指标下降幅度较小,说明龙须草对重金属复合污染具有较强的耐性,且Cd对龙须草的影响大于Pb。     

外源钙对香菇富集重金属的抑制作用

为了探明钙离子(Ca2+)对香菇富集重金属的影响,在污染4种重金属铅(Pb)、镉(Cd)、砷(As)、汞(Hg)的香菇液体培养基和栽培基质中分别添加外源Ca2+和含Ca2+矿质添加剂,以研究Ca2+对培养基和培养料污染Pb、Cd、As、Hg的香菇生长的影响和对香菇富集重金属Pb、Cd、As、Hg的影响。结果表明:外源添加的Ca2+可以显著减轻4种重金属对香菇生长的毒害作用,增加在重金属胁迫下香菇菌丝体的生物量。栽培基质中添加含Ca2+矿质添加剂显著降低了香菇子实体对4种重金属离子的大量富集。研究结果提示,Ca2+可能通过离子间的相互拮抗作用抑制了香菇对4种重金属的富集,在香菇栽培生产中,可以通过在栽培基质配方中添加含Ca2+矿质添加剂对Pb、Hg、Cd、As4种重金属的富集进行阻断。     

Absorption and Accumulation of Heavy Metal from Soil by Leaves of Populus × euramericana cv.‘ Neva' Plantation

对北京市南郊房山区107杨绿化林地进行了土壤重金属吸收富集研究,林地周围有水泥厂、石材厂、污水和垃圾等不同污染源,结果表明:林地土壤受到了Pb、Cd、Cu和Zn不同程度的污染,Pb、Cu、Zn含量差异显著,Cd平均含量(0.077 6 mg·kg-1)低于北京市背景值,但Pb、Cu、Zn平均含量分别为37.61、26.25和90.3 mg· kg-1,均超过了背景值,3块林地107杨叶片的Pb、Cd、Cu和Zn含量不同,与土壤重金属含量的变化无明显规律性,107杨叶片对土壤Pb、Cd、Cu和Zn重金属元素均能吸收富集,但对不同重金属的吸收富集能力不同,呈现出Cd＞ Zn＞ Cu＞ Pb的变化趋势,尤其对Cd具有很强的富集能力,富集系数最高值大于16,表现出了低背景高富集,而对Pb、Cu的富集能力相对较小,富集系数均小于1;不同林地107杨叶片对同种重金属元素的吸收存在较大的差异.     

土壤镉、锌、铅复合污染对芹菜的影响

采用盆栽试验,研究了红壤中Cd、Zn、Pb复合污染对芹菜生长及其重金属元素含量的影响.结果表明芹菜对Cd、Zn、Pb的吸收除了受到添加该元素的影响外,还受到共存元素的影响,且受共存元素影响的大小取决于元素间的浓度组合,即在某一点共存元素对重金属元素的拮抗或协同作用最强;正交试验方差分析结果表明,土壤添加元素对芹菜干质量及其重金属元素含量的影响均不显著;重金属元素从土壤向芹菜的迁移率大小顺序是Cd＞Zn＞Pb,Cd最易于被植物吸收;在酸性土壤中,芹菜对Cd、Zn的吸收量随土壤Cd、Zn添加量的增大而相应增加,但迁移率呈下降趋势;单一污染与复合污染对土壤重金属元素迁移率的影响无明显差异.     

资兴市铅锌尾矿库区植物资源调查及耐性植物筛选

通过对资兴铅锌尾矿区植物季节变化的调查,以及对该区植物重金属含量与分布特征的分析,初步筛选了适合于Pb、Zn尾矿库复合重金属污染土壤生态修复的植物种质资源。该区共记录高等植物81种,分属34科,其中自然定居62种,人工引种木本植物19种。重金属累积及转运特性分析表明,这些物种均对复合重金属污染具有较强的耐受性,其中,优势自然定居植物和人工栽种的木本植物对Pb、Zn富集能力均未达到超富集植物的临界阈值,一年蓬和青蒿对Cd的富集量分别达107 mg/kg和136 mg/kg,具有Cd超富集植物的基本特征,野菊花、酸模、青蒿、女贞和桂花树均具备超富集植物特征。研究结果为铅锌矿区及其污染场地生态修复提供了先锋植物和生态经济树种资源。     

常见园林树种的叶片重金属元素含量及富集特征

通过在汕头市贵屿镇重金属污染区对广东省内常见小叶榕、水翁等15种园林景观植物进行栽种试验,研究了这15种植物叶片的重金属含量及富集系数。结果表明:对Pb的富集系数最高的是小叶榕;对Cd富集系数最高的是假连翘;对Ni富集系数最高的是山杜英;对Cu富集系数最高的是大叶相思;对Hg富集系数最高的是鸡冠刺桐。可将对Pb、Cd、Ni、Cu、Hg富集能力较强的树种作为后续重金属植物修复的重点研究对象,为植物修复重金属污染提供一定的理论支持。     

绿化带土壤重金属污染特征及植物富集研究——以长沙市为例

采用原子吸收法测定长沙市交通干道绿化带15种乔木枝叶、根系及其根际土壤中重金属的含量,并分析了各树种对重金属的生物富集和转移能力。结果表明:土壤重金属污染严重,Cd的污染程度最高,其次为Cu,污染程度较轻的为Pb、Zn。乔木枝叶和根系中Zn含量最高,Cu、Pb次之,Cd最低;对土壤中Cd的生物富集最高。就综合富集系数而言,苦楝最高,为4.29;其次为樟树、法国梧桐、棕榈、桂花、盐肤木和构树。15种乔木中樟树为绿化带种植优选树种,苦楝、法国梧桐、桂花、刺槐、构树和棕榈为比较理想的绿化树种,盐肤木、旱柳、臭椿、银杏和秃瓣杜英可作为选栽树种。     

外源钙对香菇富集重金属的抑制作用1）

为了探明钙离子（Ca2＋）对香菇富集重金属的影响，在污染4种重金属铅（Pb）、镉（Cd）、砷（As）、汞（Hg）的香菇液体培养基和栽培基质中分别添加外源Ca2＋和含Ca2＋矿质添加剂，以研究Ca2＋对培养基和培养料污染Pb、Cd、As、Hg的香菇生长的影响和对香菇富集重金属Pb、Cd、As、H g的影响。结果表明：外源添加的C a2＋可以显著减轻4种重金属对香菇生长的毒害作用，增加在重金属胁迫下香菇菌丝体的生物量。栽培基质中添加含C a2＋矿质添加剂显著降低了香菇子实体对4种重金属离子的大量富集。研究结果提示，C a2＋可能通过离子间的相互拮抗作用抑制了香菇对4种重金属的富集，在香菇栽培生产中，可以通过在栽培基质配方中添加含C a2＋矿质添加剂对Pb、Hg、Cd、As4种重金属的富集进行阻断。     

107 杨对土壤重金属的吸收和富集

对北京市南郊房山区107杨绿化林地进行了土壤重金属吸收富集研究,林地周围有水泥厂、石材厂、污水和垃圾等不同污染源,结果表明:林地土壤受到了Pb、Cd、Cu和Zn不同程度的污染,Pb、Cu、Zn含量差异显著,Cd平均含量(0.077 6 mg·kg^-1)低于北京市背景值,但Pb、Cu、Zn平均含量分别为37.61、26.25和90.3 mg·kg^-1,均超过了背景值,3块林地107杨叶片的Pb、Cd、Cu和Zn含量不同,与土壤重金属含量的变化无明显规律性,107杨叶片对土壤Pb、Cd、Cu和Zn重金属元素均能吸收富集,但对不同重金属的吸收富集能力不同,呈现出Cd>Zn>Cu>Pb的变化趋势,尤其对Cd具有很强的富集能力,富集系数最高值大于16,表现出了低背景高富集,而对Pb、Cu的富集能力相对较小,富集系数均小于1;不同林地107杨叶片对同种重金属元素的吸收存在较大的差异。     

Phytoremediation Characteristics of Pb and Cd Contaminated Soils by Ginkgo Seedling

In this article,we investigated effects of lead and cadmium on the biomass of ginkgo seedlings, and roles of the seedlings in accumulation characteristics of the heavy metals and remediation of the soil contaminated by Cd²⁺ or Pb²⁺ as well as their combination.The results showed that both Cd²⁺ and Pb²⁺ significantly or very significantly reduced biomass increment of ginkgo seedlings,with Pb²⁺ more adverse than Cd²⁺.The Cd²⁺-Pb²⁺ compound pollution further reduced biomass increment of ginkgo seedlings.The mass fractions and enrichment coefficient of Pb²⁺ and Cd²⁺ in ginkgo seedlings were in an order of root>stem>leaf,which was in favor of transportation Pb²⁺ and Cd²⁺ from root to stem and leave.The Cd²⁺-Pb²⁺ compound pollution promoted ginkgo seedling absorption to Cd²⁺ and Pb²⁺.The capacity of the upward transport of Pb²⁺ was greater than that of Cd²⁺,which suggested an obvious dose-effect and synergistic effect.Cd²⁺ and Pb²⁺ accumulations in ginkgo seedlings were relatively large.The accumulation in roots was higher than that in stems and leaves.The ability of the absorption,transportation and accumulation of ginkgo seedlings to Pb²⁺ was relatively greater under Cd²⁺-Pb²⁺ compound pollution.The phytoremediation efficiency of Cd²⁺ and Pb²⁺ was relatively high.     

Exogenous application of succinic acid enhances tolerance of Larix olgensis seedling to lead stress

Larix olgensis A. Henry(Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead(Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid(SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04,0.2, 1.0, or 2.0 mmol kg~(-1) of soil for 10, 20, and 30 days,respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots,stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde(MDA) content and electrolyte leakage in leaves significantly increased while peroxidase(POD) activities, soluble protein and photosynthetic pigment contents in leaves were all reduced.Physiological toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA(especially 10.0 mmol L-1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically increased.SA facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.     

Absorption and Accumulation of Heavy Metal from Soil by Leaves of Populus x euramericana cv.‘Neva’Plantation

The absorption and enrichment of heavy metal elements by leaves of Populus×euramericana cv.’Neva’ were analyzed through content assessing of heavy metal elements in soils of three forest lands at Fangshan District in the southern suburb of Beijing. These forest lands with P.×euramericana cv. ’Neva’plantation were around with the various sources of pollution such as cement mill,stone mill, sewage and garbage.Some of heavy metal elements such as Cd,Pb,Cu,and Zn were found in the soil samples and leaves of P.×euramericana cv.’Neva’ grown on the three forest lands which were investigated.The results of investigation showed that the soils of three forest lands were polluted with Pb, Cd,Cu and Zn in varying degrees.The contents of Pb,Cu and Zn in soils were significantly different among the three forest lands,whereas the average content of Cd(0.077 6 mg·kg^-1) was less but that of Pb,Cu,and Zn(37.61,26.25 and 90.3 mg·kg^-1 ) were more than the average background value of Beijing.The contents of Pb,Cd,Cu and Zn in leaves of P.×euramericana cv.’Neva’ were different among three forestlands.With the changes of heavy metal contents in soil samples,there was no regularity on the changes of different heavy metal contents in leaves of P.×euramericana cv.’Neva’ grown on different forest land.P.×euramericana cv.’Neva’ can absorb and accumulate Pb,Cd,Cu and Zn in soil but showed different capacities of absorption and accumulation with the order of Cd>Zn>Cu>Pb.Especially,its absorption and accumulation capacity for Cd was strong with maximum enrichment factor higher than 16 and showed high accumulation on low background,whereas its enrichment capacities for Pb and Cu were relatively poorer with average enrichment factor of less than 1.At different forest lands,there existed great difference on absorption capacity of P.×euramericana cv.’Neva’ with the same heavy metal.     

树叶中重金属含量及其指示大气污染的研究

通过对南京市区交通流量大的区域和相时清洁区(江苏省林科院)不同植物叶片重金属元素(Pb、Cd、Cu)含量的分析,研究了大气污染指数,初步探讨了植物重金属含量与城市大气污染之间的关系.研究表明.植物叶片中重金属Pb、Cd和Cu的累积量与大气中Pb、Cd和Cu的相对含量呈显著正相关;所调查绿化树种叶片的重金属含量因重金属种类、采样区和树种的不同具有明显差异,悬铃木叶片累积Pb的能力最强,而杨树叶片对Cd和Cu的累积能力最强.市区大气重金属质量状况为:交通枢纽区中央门、南京化工厂和沪宁高速属于重污染,生活区新庄属于中轻度污染,远郊林科院属于无污染区.     

银杏活性炭对4种有毒气体和铅镐离子的吸附作用

为了验证银杏活性炭的吸附效果,分别采用静态吸附法和动态吸附法,研究了银杏活性炭对部分有毒气体及铅、镉两种重金属离子的吸附作用.结果表明:银杏活性炭对甲醛、苯、氨气、三氯甲烷这4种气体的吸附能力都较强,其对甲醛的吸附能力最强.吸附率可达到140%;银杏活性炭吸附铅、镉离子的效果也较好,对铅离子的吸附量接近200 mg·g...     

Exogenous application of succinic acid enhances tolerance of <Emphasis Type="Italic">Larix olgensis</Emphasis> seedling to lead stress

Larix olgensis A. Henry (Changbai larch) is a productive commercial species and good candidate for afforestation in northeast China. It is widely planted in lead-stressed soils which can induce oxidative damage in this plant. Increasing tolerance to lead (Pb) stress is therefore of keen interest. A greenhouse experiment was conducted to identify the biomass, physiological responses and Pb accumulation of L. olgensis seedlings to Pb stress under succinic acid (SA) application and to explore the interaction of exogenous SA applications and stress resistance. L. olgensis seedlings were planted in Pb-stressed or unstressed haplic cambisols in pots. In Pb-contaminated soils the seedlings were treated daily with concentrations of SA solutions at a rate approximately equivalent to 0, 0.04, 0.2, 1.0, or 2.0 mmol kg^?1 of soil for 10, 20, and 30 days, respectively. Pb treatment induced damage in the seedlings and led to the inhibition of biomass accumulation in roots, stems and leaves, and a rise in Pb accumulation in fine roots and leaves. Malondialdehyde (MDA) content and electrolyte leakage in leaves significantly increased while peroxidase (POD) activities, soluble protein and photosynthetic pigment contents in leaves were all reduced. Physiological toxicity was promoted with increasing Pb treatment times. When Pb-stressed seedlings were exposed to SA (especially 10.0 mmol L^?1 over 20 days), the physiological responses for Pb-only were reversed and the biomass of roots, stems, and leaves dramatically increased. SA facilitated Pb uptake in fine roots and leaves but more Pb accumulated in fine roots. The results demonstrate that exogenous SA alleviates Pb-induced oxidative injuries and improves the tolerance of L. olgensis seedlings to Pb stress.     

10个常绿树种对砷汞铅镉铬的富积能力研究

通过对10个常绿树种在昆钢污染区和对照叶片中砷、汞、铅、镉、铬5种重金属元素含量的试验测定,分析了各个树种对重金属的富积能力.结果表明,同一树种对不同类型重金属元素的富积能力不同,不同的树种对同一类型重金属的富积能力也有很大差异;参试的10个树种均对重金属元素表现出较好的抗性和富积能力,其中对砷、汞、铅、镉、铬的富积能力最强的树种分别是鳞斑荚蒾、红果树、鳞斑荚蒾、金叶子和云南泡花树.污染物中砷、铅、铬和镉的含量占了较大比重,各重金属元素在污染时存在相互关联.按综合富积能力排序,依次是鳞斑荚蒾＞茶条木＞云南泡花树＞云南卫矛＞红果树＞飞蛾槭＞子楝树＞滇青冈＞金叶子＞云南木樨榄.     

洪泽湖沉积物中重金属的污染测定及评价

选取洪泽湖为研究对象,于2008年采集洪泽湖沉积物样品17个,以沉积物中6种重金属（Cu、Cd、Pb、Zn、Ni、Cr）的总量为主要研究内容,运用潜在生态危害指教法对沉积物中的重金属污染状况进行了评价。结果表明：洪泽湖Cu、Ni、Zn、Pb、Cr污染的主要分布在东部和北部湖区,Cd污染主要在西部湖区。Pb是全湖污染最严重的重金属。Cu、Ni、Zn、Pb、Cr的潜在生态危害较小（低风险）,Cd的潜在生态危害较大（高风险）,总的潜在生态危害为低风险,Cd的影响最大（达到81％）。