EDTA-enhanced phytoremediation of lead contaminated soil by Bidens maximowicziana

Phytoremediation is a potential cleanup technology for the removal of heavy metals from contaminated soils.Bidens maximowicziana is a new Pb hyperaccumulator,which not only has remarkable tolerance to Pb but also extraordinary accumulation capacity for Pb.The maximum Pb concentration was 1509.3 mg/kg in roots and 2164.7 mg/kg in overground tissues.The Pb distribution order in the B. maximowicziana was:leaf>stem>root.The effect of amendments on phytoremediation was also studied.The mobility of soil Pb and the Pb concentrations in plants were both increased by EDTA application.Compared with CK(control check),EDTA application promoted translocation of Pb to overground parts of the plant.The Pb concentrations in overground parts of plants was increased from 24.23-680.56 mg/kg to 29.07-1905.57 mg/kg.This research demonstrated that B.maximowicziana appeared to be suitable for phytoremediation of Pb contaminated soil,especially,combination with EDTA.     

超积累植物龙葵及其对镉的富集特征

超积累植物筛选是重金属污染土壤植物提取修复的基础和核心问题,同时也是污染环境植物修复的难点及前沿.杂草具有抗逆境能力强、生长迅速、繁殖能力强以及在环境条件适宜情况下生物量能够急剧提高等特点,可以弥补现有超积累植物的某些缺点和不足,是较理想的超积累植物资源.本文通过室外盆栽模拟试验及重金属污染区采样分析试验,首次发现并证实杂草龙葵(Solanumnigrum L .)是一种Cd超积累植物.其中,盆栽试验表明,在Cd污染水平为25mg/kg条件下,龙葵茎及叶的Cd含量分别超过了100mg/kg这一公认Cd超积累植物应达到的临界含量标准,其地上部Cd含量大于其根部Cd含量,且地上部Cd富集系数大于1 ,同时,与对照相比,植物的生长未受到抑制.污染区采样分析试验进一步表明,龙葵对Cd的富集符合Cd超积累植物的基本特征.这一通过未污染区对超积累植物进行筛选的方法,可以为Cd污染土壤的植物修复获得更多具有实用价值的新材料.     

EDTA调控下灯心草和龙须草对铅锌尾矿污染土壤的修复潜力

采用盆栽试验,研究了不同质量摩尔浓度EDTA(b(EDTA))调控下灯心草和龙须草对铅锌尾矿污染土壤的修复潜力.结果表明:当b(EDTA)为0.125～2.000 mmol/kg时能显著促进生长在铅锌尾矿污染土壤中灯心草和龙须草地上部生物量的增产,分别在0.500和1.000 mmol/kg时达到最大值.EDTA对2种草地上部生物量的影响大于地下部,分别通过影响株高和分蘖数实现,且对灯心草的影响程度大于龙须草.添加EDTA可以显著提高2种草对各重金属的富集能力,尤其以Pb, Cu最为明显.同时发现,EDTA对植物积累重金属能力的促进作用存在植物种类和重金属元素种类之间的差异.灯心草和龙须草分别在重金属积累、转运和生物量上存在优势,在EDTA调控下将2种植物合理搭配种植在铅锌尾矿污染土壤中能取得良好的重金属去除效果.      

Selection of appropriate organic additives for enhancing Zn and Cd phytoextraction by hyperaccumulators

Chelant-enhanced phytoextraction is one of the most promising technologies to remove heavy metals from soil. The key of the technology is to choose suitable additives in combination with a suitable plant. In the present study, laboratory batch experiment of metal solubilization, cress seeds germination were undertaken to investigate the metal-mobilizing capability and the phytotoxicity of organic additives, including ethylene diamine triacetic acid （EDTA）, citric acid, acetic acid, oxalic acid, glutamine and monosodium glutamate waste liquid （MGWL） from food industry. Experiments in pots were carried out to study the effects of the additives on Zn and Cd phytoextraction. Furthermore, a leaching experiment with lysimeter was performed to evaluate the environmental risks of additive-induced leaching to underground water. The results showed that EDTA had a strong mobilizing ability for Zn and Cd, followed by mixed reagent （MR） and MGWL. MGWL and acetic acid at 5 mmol equivalent per liter resulted in seed germination index less than 2%. Experiments in pots verified the phytotoxicity of acetic acid and MGWL. Addition of the mixed reagent at 6--10 mmol/kg significantly increased Zn phytoextraction by Thlaspi caerulescens. The same for EDTA and the mixed reagent at 10 mmol/kg by Sedum dfredii. But only mixed reagents could significantly increase Cd phytoextraction by the studied hyperaccumulators. This suggested that the strong chelant was not always the good agent to enhance phytoextraction. S. alfredii combined with 2--10 mmol/kg soil MR was preferred for phytoremediation of Cd/Zn contaminated soils in southern China, this could result in high phytoextraction of Cd/Zn and reduce the leaching risk to underground water than EDTA assisted phytoextration.     

Elemental sulfur effects on Pb and Zn uptake by Indian mustard and winter wheat

A pot experiment was conducted to investigate the influence of elemental sulfur to contaminated soil on plant uptake by a heavy metal hyperaccumulator, Indian mustard( Brassica juncea ) and a field crop, winter wheat( Triticum. aestivum). Elemental sulfur(S) with different rates was carried out, they were 0(S0 ), 20(S20 ), 40(S40 ), 80(S80 ), and 160(S160 ) mmol/kg respectively. Extra pots with the same rates of S but without plants were used for soil sampling to monitor pH and CaCl2-extractable heavy metal changes. The results showed that S enhanced phytoextraction of Pb and Zn from contaminated soil. Application S effectively decreased soil pH down to 1.1 as the most at the rate of Sl60. The concentrations of CaCl2-extractable Pb and Zn in soil and uptake of Pb and Zn by the plants were increased with soil pH decreased. A good correlation between CaCl2-extractable Pb/Zn and soil pH was found( Rpb^2 = 0.847 and RZn^2 = 0,991, n = 25). With S application, soil CaCl2-extractable Pb and Zn concentrations, concentration of Pb and Zn in plants and the amount of removal by plant uptake were significanfly higher than those without S. Under the treatment of S160, the highest CaCl2-extmctable Pb and Zn were observed, they were 4.23 mg/kg and 0.40 mg/kg, 2.7 and 2.0 times as that of the control(So ) respectively. At the highest rates of S( Sl~0 ), both Indian mustard and winter wheat reached the highest uptake of Pb and Zn. The highest Pb concentrations in wheat and Indian mustard were 32.8 mg/kg and 537.0 mg/kg, all 1.8 times as that of the control, and the highest Zn concentrations in wheat and Indian mustard were 215.5 mg/kg and 404.0 mg/kg, 2.4 and 2.0 times as that of the control respectively. The highest removals of Pb and Zn from the contaminated soil were 0.41 rag/pot and 0.31 nag/pot by Indian mustard in the treatment of S160 through 50 days growth.     

Removal of metals by sorghum plants from contaminated land

The growth of high biomass crops facilitated by optimal of agronomic practices has been considered as an alternative to phytoremediation of soils contaminated by heavy metals. A field trial was carried out to evaluate the phytoextraction efficiency of heavy metals by three varieties of sweet sorghum (Sorghum biocolor L.), a high biomass energy plant. Ethylene diamine tetraacetate (EDTA), ammonium nitrate (NH₄NO₃) and ammonium sulphate ((NH₄)₂SO₄) were tested for their abilities to enhance the removal of heavy metals Pb, Cd, Zn, and Cu by sweet sorghum from a contaminated agricultural soil. Sorghum plants always achieved the greatest removal of Pb by leaves and the greatest removal of Cd, Zn and Cu by stems. There was no significant difference among the Keller, Rio and Mray varieties of sweet sorghums in accumulating heavy metals. EDTA treatment was more efficient than ammonium nitrate and ammonium sulphate in promoting Pb accumulation in sweet sorghum from the contaminated agricultural soil. The application of ammonium nitrate and ammonium sulphate increased the accumulation of both Zn and Cd in roots of sorghum plants. Results from this study suggest that cropping of sorghum plants facilitated by agronomic practices may be a sustainable technique for partial decontamination of heavy metal contaminated soils.     

浒苔生物炭促进土壤Pb固定并缓解植物Pb毒性

本文利用浒苔在不同温度下制备的生物炭（400℃和600℃,记为BC400与BC600）,以30g/kg生物炭添加量对1200mg/kg的Pb污染土壤进行香根草盆栽实验,研究浒苔生物炭对土壤中Pb固定和植物中Pb毒性的影响.结果表明,浒苔生物炭与香根草能协同促进土壤中Pb固定,较生物炭组提高了16.89%和14.82%,比植物组提高17.40%和15.02%.生物炭理化性质影响Pb固定,BC400的pH值（8.97）低于BC600（10.59）,但BC400固定Pb的效果优于BC600,因为羟基（—OH）、羰基（C═O）等基团较BC600丰富,且微孔结构完整.浒苔生物炭可抑制香根草对Pb的吸收,促进香根草生长,其中BC400有助于植物地上部分及根部Pb浓度降低（分别降低23.50%和22.92%）,同时降低富集系数,提高香根草的生物量、叶绿素含量及根系活力,提高抗氧化酶SOD、CAT和POD活性,丙二醛含量可降低13.40%.总之,浒苔生物炭通过高pH值和微孔结构吸附Pb,并通过官能团增加与金属的结合位点固定Pb,以降低Pb的毒性,提高香根草生存能力.鉴于滨海地区浒苔生物质资源丰富,生物炭与植物联合作用可作为Pb污染土壤修复的技术措施之一.     

羽叶鬼针草对Pb的吸收特性及修复潜力

羽叶鬼针草对土壤中Pb的吸收特性和修复潜力的研究结果表明:①鬼针草对Pb有很强的吸收能力,在土壤Pb浓度为2 000mg·L^-1时,鬼针草地上部和根系中Pb含量达到最高,分别为2 164.7mg·kg^-1和1 509.3 mg·kg^-1;②鬼针草植物对Pb的吸收有很强的分异特征,植物吸收的Pb主要富集于地上部,Pb在植物体内的分布规律是叶子>茎>根系>种子;③不同生长期植物对Pb的吸收速度是不同的,植物在开花期对Pb的吸收速度最大,吸收量根系为15.81 mg·(kg·d)^-1,地上部是19.83 mg·(kg·d)^-1.羽叶鬼针草具备修复土壤Pb污染的潜力.     

钝化剂与肥料对油菜和孔雀草间作体系的影响

通过盆栽实验,采用镉（Cd）低积累油菜单作和低积累油菜-超富集植物孔雀草间作两种种植模式,设置施用巯基坡缕石和硫酸钾以及叶面喷施硫酸锰的调控处理,研究不同处理对单作和间作模式下植物生长与Cd累积以及土壤Cd形态的影响.结果表明：施用巯基坡缕石可显著降低油菜和孔雀草地上部Cd含量、油菜Cd累积量、Cd提取率以及土壤有效态Cd含量.施用0.4g/kg的硫酸钾显著增加孔雀草Cd累积量,降低间作油菜地上部Cd含量,使间作油菜根际土壤可交换态Cd比例减少,残渣态Cd比例增加.喷施0.6g/L的硫酸锰使单作油菜地上部Cd含量、Cd累积量以及Cd提取率显著降低.从降低油菜地上部Cd含量保障安全生产,同时不影响Cd植物提取修复角度综合考虑,在间作模式下,施用0.4g/kg的硫酸钾处理调控效果最佳.     

两种外源有机酸对土壤Cd形态及秋华柳Cd积累的影响

秋华柳(Salix variegate Franch.)因具有良好的重金属耐受和积累能力,常被作为重金属污染土壤修复工程物种.通过盆栽模拟试验,分析了不同浓度外源草酸和酒石酸处理下土壤Cd形态的变化和秋华柳Cd含量的积累特征,以探究外源有机酸在Cd污染土壤植物修复中的应用潜力.结果表明:添加外源酒石酸可显著降低土壤非有效性Cd含量,增加土壤中以可交换态Cd为主的有效性Cd含量,促进了秋华柳对Cd的积累,同时也显著提升了植株的富集系数,其中添加5 mmol/kg酒石酸的处理效果最佳.与CK相比,添加5 mmol/kg外源酒石酸可显著增加秋华柳根、茎和叶中的Cd积累量,地上、地下部分和全株的Cd积累量分别提升了62.2%、75.9%和78.4%,地上和地下部分富集系数分别提升了173.0%和178.8%.添加外源草酸对土壤有效性Cd含量没有显著影响,秋华柳根、茎和叶的Cd含量和积累量无明显提升.研究显示,添加较低浓度的酒石酸更有利于增加土壤中可交换态Cd含量和有效性Cd含量,促进秋华柳对土壤中Cd的吸收和积累,增强秋华柳对Cd污染土壤的修复能力,可应用于Cd污染土壤的植物修复.      

印度芥菜和香根草对Pb污染土壤的修复效能及作用途径

为探究印度芥菜(Brassica juncea)和香根草(Vetiveria zizanioides L.)对Pb污染土壤的修复效能和作用途径,采用Pb污染土壤〔w(Pb)为400~2 000 mg/kg〕进行为期30 d的盆栽试验,分析植物对Pb的耐受性、积累能力和固定效果.结果表明:① 印度芥菜和香根草对Pb的积累主要集中在根部,两种植物根部累积的w(Pb)分别为206.62~902.40和288.42~1 102.47 mg/kg,单株植物的Pb积累量分别为70.75~138.31和99.09~220.49 μg,香根草对Pb污染土壤的修复效能高于印度芥菜. ② 印度芥菜和香根草对Pb的去除率随土壤中w(Pb)的增加而降低,对Pb的固定率则随土壤中w(Pb)的增加而增加,二者对Pb的去除率最大值分别为1.02%和1.78%,对Pb的固定率可达11.22%和16.78%,两种植物对Pb污染土壤修复的主要途径为植物固定. ③ 主成分分析表明,w(脯氨酸)对植物Pb积累过程具有重要作用.研究显示,相比于印度芥菜,香根草更适用于Pb污染土壤的植物修复.      

Woody species Rhus chinensis Mill. seedlings tolerance to Pb: Physiological and biochemical response

Screening potential plant species is a crucial consideration in phytoremediation technology. Our previous study demonstrated that Rhus chinensis Mill. seedlings had potentials for phytoremediation of Pb contaminated soil. However, its bioaccumulation and tolerance characteristics remain unclear. Seedling growth, LMWOAs secreted by roots, Pb subcellular distribution and chemical forms, and mineral elements in R. chinensis tissues were evaluated under different Pb concentrations (0, 25, 50, 100, 200 and 400?mg/L) in culture solution at 14?days after planting. R. chinensis did not show visual symptoms of Pb toxicity under lower Pb treatments; however, Pb significantly declined the growth of seedlings under higher Pb treatments. Higher Pb stress also decreased the concentrations of nitrogen in leaves, but increased the concentrations of P and K in roots. Pb stress also decreased Mn concentrations in leaves. A great quantity of Pb was uptake and mostly retained in R. chinensis roots. Nonetheless, R. chinensis can still concentrate 459.3 and 1102.7?mg/kg Pb in leaves and stems, respectively. Most of Pb in R. chinensis tissues was stored in the cell wall with HAc-, HCl-, and NaCl-extractable form. LMWOAs secreted by R. chinensis roots showed a strong positive correlation with Pb concentrations in all plant tissues and with P in roots. Our results suggested that Pb deposited in the cell wall and integration with phosphate or oxalate might be responsible for the tolerance of R. chinensis under Pb stress in short period.     

三七及种植土壤重金属污染特征与风险评价

以主产地云南省文山州三七及其种植土壤为研究对象,测定土壤和三七地上和地下部重金属镉（Cd）、砷（As）、铅（Pb）含量,揭示三七对重金属的吸收转运特征,通过分析重金属日摄入量（ADI）和靶标危害商数（THQ）,评估三七中Cd、As、Pb的食品安全风险和人体健康风险.结果表明：种植土壤Cd、As含量为0.07~4.1和13.9~310mg/kg,超标率为63.2%和79%,Pb未超标;综合污染指数P>3,均值3.52,表明达重度污染等级;Cd、As单因子污染指数P_Cd/As>1的土壤样品占比为63.2%和84.2%,表明土壤Cd、As达轻度污染等级.三七地上和地下部Cd、As、Pb含量分别为0.05~0.69、0.07~0.73,0.25~1.06、0.09~1.73和0.12~1.13、0.07~0.66mg/kgdw,Cd超标率为26.3%~36.8%,As、Pb无超标,表明三七易吸收Cd且存在超标现象,需重点关注.三七Cd含量与土壤Cd含量呈极显著正相关（p<0.01）,As、Pb表现为负相关,生物浓缩因子BCF_Cd=0.03~3.5,BCF_As和BCF_Pb均<1,进一步表明三七对Cd具有较强的富集能力;转运系数表现为：TF_Pb（3.53）>TF_As（2.32）>TF_Cd（0.59）,表明三七易将吸收的Cd储存于主要食用部位地下部（主根）,其食品安全风险和人体健康风险值得关注.三七Cd、As、Pb每日摄入量均值分别为0.0026~0.0035、0.0043~0.0066和0.0026~0.0059mg/d,每日摄入量占每日允许摄入量ADI标准限值的百分比为3.3%~4.7%、4.3%~5.8%和1.2%~2.7%,表明三七中Cd、As具有较高的食品安全风险（ADI>1%）.三七Cd、As、Pb靶标危害商数THQ>1的占比分别为42.1%~68.4%、84.2%~100%和0~31.6%,表明长期食用三七摄入Cd、As具有潜在人体健康风险.     

Effects of EDTA and plant growth-promoting rhizobacteria on plant growth and heavy metal uptake of hyperaccumulator Sedum alfredii Hance

Phytoremediation is a cost-effective and environment-friendly strategy for decontaminating heavy-metal-contaminated soil. However, the practical use of phytoremediation is constrained by the low biomass of plants and low bioavailability of heavy metals in soil. A pot experiment was conducted to investigate the effects of the metal chelator ethylenediaminetetraacetic acid (EDTA) and EDTA in combination with plant growth-promoting rhizobacteria (Burkholderia sp. D54 or Burkholderia sp. D416) on the growth and metal uptake of the hyperaccumulator Sedum alfredii Hance. According to the results, EDTA application decreased shoot and root biomass by 50% and 43%, respectively. The soil respiration and Cd, Pb, Zn uptake were depressed, while the photosynthetic rate, glutathione and phytochelatin (PC) contents were increased by EDTA application. Interestingly, Burkholderia sp. D54 and Burkholderia sp. D416 inoculation significantly relieved the inhibitory effects of EDTA on plant growth and soil respiration. Compared with the control, EDTA + D416 treatment increased the Cd concentration in shoots and decreased the Pb concentration in shoots and roots, but did not change the Zn concentration in S. alfredii plants. Furthermore, EDTA, EDTA + D54 and EDTA + D416 application increased the cysteine and PC contents in S. alfredii (p < 0.05); among all tested PCs, the most abundant species was PC2, and compared with the control, the PC2 content was increased by 371.0%, 1158.6% and 815.6%, respectively. These results will provide some insights into the practical use of EDTA and PGPR in the phytoremediation of heavy-metal-contaminated soil by S. alfredii.     

5种矿区土著植物对铅污染土壤的修复潜力研究

为评估我国西北某矿区茵陈蒿、蒲公英、苜蓿、大叶苦菜和车前草5种土著作物对含铅（Pb）土壤的修复潜力,采用盆栽实验,设置4种不同Pb含量水平（0、2‰、3‰和5‰,质量分数）,测定作物不同组织器官中和种植前后土壤中Pb含量,以及根际与非根际土壤微生物生物量碳含量、过氧化氢酶活性等指标。结果表明:茵陈蒿和车前草适合种植于铅含量为2‰、3‰、5‰的土壤中,可去除12%~32%的土壤Pb,车前草根系和茵陈蒿茎叶对Pb的累积量最高分别达到3617,720 mg/kg,显著高于其他植物,作为土壤铅污染修复植物的潜力较大。根际土壤微生物生物量碳含量比非根际土壤微生物生物量碳含量高2.37%~13.89%。土壤Pb抑制了根际与非根际土壤过氧化氢酶活性,使其活性低于对照组0.44%~22.3%,根际土壤过氧化氢酶活性比非根际过氧化氢酶活性高0.89%~8.09%。研究结果可为Pb污染矿区废弃地植物修复和土壤环境质量评价提供理论依据。     

锌冶炼厂周围重金属在土壤-蔬菜系统中的迁移特征

采用对应采样方法研究了葫芦岛锌冶炼厂周围土壤、蔬菜中Hg、Pb、Cd、Zn、Cu的含量及其在土壤-蔬菜中的传递,分析了土壤、蔬菜中重金属的来源.结果发现锌厂周围土壤、蔬菜受到重金属的严重污染.蔬菜可食用部分Hg、Pb、Cd、Zn、Cu的含量(以鲜重计)最高可分别达到0.013、5.476、2.852、41.16和1.515 mg/kg.通过转移因子的比较分析,锌厂周围重金属在土壤-蔬菜中的转移能力为Cd＞Zn＞Cu＞Pb＞Hg,重金属从土壤向蔬菜叶片中的转移能力高于蔬菜的其它器官.土壤中重金属主要来源于锌厂周围的大气.蔬菜叶片中的Pb可能部分来源于大气,而汞则主要来源于大气.     

Phytoremediation for phenanthrene and pyrene contaminated soils

Phytoremediation of soil contaminated with phenanthrene and pyrene was investigated using twelve plant species. Plant uptake nd accumulation of these chemicals were evaluated. At the end of the experiment(45 d), the remaining respective concentrations of soil henanthrene and pyrene in spiked vegetated soils, with initial phenanthrene of 133.3 mg/kg and pyrene of 171.5 mg/kg, were 8.71-16.4 nd 44.9-65.0 mg/kg, generally 4.7%-49.4% and 7.1%-35.9% lower than their concentrations in the non-vegetated soils. The loss f phenanthrene and pyrene in vegetated spiked soils were 88.2%-93.0% and 62.3%-73.8% of the added amounts of these ontaminants, respectively. Although plant uptake and accumulation of these compounds were evident, and root concentrations and RCFs(root concentration factors; defined as the ratio of PAH concentrations in roots and in the soils on a dry weight basis) of these compounds ignificantly positively correlated to root lipid contents, plant uptake and accumulation only accounted for less than 0.01% and 0.23% of the nhanced loss of these chemicals in vegetated versus non-vegetated soils. In contrast, plant-promoted microbial biodegradation was the ominant mechanism of the phytoremediation for soil phenanthrene and pyrene contamination. Results from this study suggested a easibility of the establishment of phytoremediation for soil PAH contamination.     

EDTA对4种花卉富集Cd、Pb的效应

植物提取修复技术(Phytoremediation)是一种环境友好的重金属污染土壤原位修复技术,但是修复植物的提取效率经常受到目标金属的低植物有效性所限制。通过盆栽试验研究了乙二胺四乙酸(ethylenedi-aminetetraacetic acid,EDTA)对4种花卉富集Cd、Pb效应的影响。结果表明:施加EDTA溶液(3mmol/kg)7d后,矮牵牛、万寿菊、彩叶草叶部Cd含量显著增加(P<0.05);所选4种花卉叶部Pb的含量均极显著增高(p<0.01)。施加EDTA后万寿菊对Cd和孔雀草对Pb的富集系数和转移系数均达到了1以上,这表明这两种植物可用于螯合辅助植物提取方式的污染土壤修复。     

锰矿修复区泡桐与栾树生长与重金属积累特性

在湘潭锰矿废弃地种植泡桐和栾树,建立了4hm²生态修复示范区.工程区基质Mn平均含量高达20041mg/kg,Pb、Zn、Cu、Cd含量也远超过湖南省和全国的背景值,属复合型重度污染.污染区不覆土,苗木移植前每株根际定量施用了含有自污染区矿渣分离出的抗性菌株的专用有机肥.种植两年后,泡桐和栾树成活率均达到83%以上.泡桐生长状况明显优于栾树,两种植物叶的重金属含量均大于根和茎,泡桐Mn、Cu、Zn的浓度和积累量显著高于栾树.5年生泡桐Mn积累量达到2295g/hm²,转运量系数为2.32.试验证明,采用有机菌肥改良根际环境后,泡桐与栾树均可作为锰污染区的修复树种,而泡桐的生长速率和重金属的耐受和积累性能优于栾树.     

碎米荠对硒、镉超富集特性研究

超富集植物在营养元素生物强化及重金属污染植物修复技术领域有重大应用前景。通过野外调查和栽培实验,研究了碎米荠植物对硒镉的吸收富集特征。研究表明:野生碎米荠中Se含量达数百mg/kg,叶片中Se最高含量为1 365 mg/kg。地上部Se的生物富集系数在2.8~43.8的范围内,大部分超过10;生物转移系数在0.46~1.88之间,大部分大于1。地上部Cd含量都超过了100 mg/kg,叶中的Cd含量大部分在400~800 mg/kg之间。富集系数都大于1,且农田及小溪流域植株地上部Cd的生物富集系数高达几十甚至上百,Cd的生物转移系数大部分超过1。露天栽培条件下,碎米荠中的硒镉含量随盆栽土壤中硒镉浓度的上升呈现出先增加后降低的特征,当Se含量为50 mg/kg时植物中的Se含量最高,此时地上部Se含量为995 mg/kg,地下部Se含量1 100 mg/kg。当Cd浓度为80 mg/kg时,植株当中Cd含量最高,地上部和地下部中的Cd含量分别高达550 mg/kg、337 mg/kg。研究认为湖北渔塘坝发育的碎米荠植物是硒镉多元素超富集植物,在硒镉生态环境污染修复方面具有重大应用前景。