镉超富集植物东南景天根系分泌物的代谢组学研究

利用基于气相色谱-质谱联用技术(GC-MS)的代谢组学方法,寻找不同处理条件间差异显著的镉超富集植物东南景天根系分泌物质,并探讨它们对东南景天耐受或超富集镉的可能作用机制。收集0和40μmol/L镉分别处理4和8天后的东南景天根系分泌物样品,通过样品冻干、甲醇溶解、甲氧胺盐酸盐和N-甲基-N-(三甲基硅烷)三氟乙酰胺衍生化处理、GC-MS检测的分析过程,得到根系分泌物的表达谱。主成分分析和正交偏最小二乘判别分析(OPLS-DA)得分图可将不同处理条件间东南景天的根系分泌物质明显区分,运用OPLS-DA载荷图、模型的变量重要性因子和方差分析发现12个根系分泌物质在4组间存在显著性差异。它们的相对含量在不同处理条件间的变化趋势明显不同,表明东南景天可通过调节它们的分泌来耐受或超富集重金属镉。     

重金属污染土壤植物修复的强化措施研究进展

植物修复是一种有着巨大市场潜力的治理重金属污染土壤的技术,由于影响植物修复效率的因素较多,至今实际应用还很少。针对目前植物修复技术的不足,主要从植物本身的性能、重金属的生物有效性以及农艺管理措施等三方面,综述了近年来国内外有关植物修复强化措施的研究进展,并展望了今后该领域的研究方向。     

重金属污染土壤修复技术研究进展

概述了土壤重金属污染的特点、现状及污染的来源,主要从工程措施、农业措施、改良措施和生物修复措施四方面对国内外各种修复技术进行分析与评论,指出各类措施的原理、优缺点、实用性。同时,提出了当前土壤重金属污染与修复技术研究的重点。     

特选榨菜对铀污染土壤的修复评价

本文通过两种不同的加铀方式,加入不同种类及浓度的螯合剂,以及土壤改良剂(有机肥、微生物肥料、腐殖酸、尿素)的方法,研究了不同因素对特选榨菜修复铀污染土壤的影响。结果表明:在pH=5时把UO_2(NO_3)_2·6H_2O溶液喷洒入土壤,使土壤中铀污染浓度为100 mg·kg~(-1)时,特选榨菜地上部铀富集的浓度最大可以达到1103.42 mg·kg~(-1),根部为1909.49 mg·kg~(-1),去除率为7.81%;上述含铀土壤放置2年后制备成模拟铀污染的土壤,进而栽种特选榨菜进行修复,在100 mg·kg~(-1)铀污染浓度下,植物上部铀富集浓度最大为295.83 mg·kg~(-1),根部为268.42 mg·kg~(-1),年去除率为2.52%。用Tessier五步连续提取法测定两次修复土壤中铀的形态,发现模拟铀污染土壤比铀喷洒于土壤中有效态的铀(交换态和碳酸盐结合态)要低52.7%;加入柠檬酸、苹果酸等螯合剂以及有机肥、微生物肥料、腐殖酸、尿素等土壤改良剂,在模拟铀污染土壤修复时发现有机肥会降低植物上部对铀的富集;而柠檬酸和微生物肥会增强植物上部对铀的富集。     

柠檬酸对电动修复铬镍复合污染土壤的影响

通过分析不同电动修复时间对土壤的电流、pH、电导率及铬镍去除率的影响确定最佳电动修复时间为5 d.再通过正交解吸实验,考察阴极控制液和控制液浓度对电动修复铬镍复合污染土壤的影响.结果表明柠檬酸是EDTA、柠檬酸、酒石酸、乙酸四种常见阴极控制液中的最佳控制液,其最佳浓度为0.1 mol/L.在最佳的修复实验条件下铬的去除率可以达到61.76%,但是镍的修复率只有16.29%,这可能是由于加了阴极控制液后最佳修复时间应该适当延长.     

土壤硒污染的生物修复技术

硒是一种较特殊的微量元素，人和动物缺硒和硒中毒之间的范围很窄，土壤硒污染能对当地的人和动物产生重大伤害。采用传统的土壤污染治理方法，成本高，效果差，而近年来兴起的生物修复技术是治理土壤硒污染的既有效又经济的方法。     

污染土壤的物化修复治理技术研究

污染土壤的修复治理过程中,物化技术以其快速高效的特点成为国内外研究的热点。本文通过对工程措施、玻璃化技术、热修复、电动力修复、光化学降解、化学淋洗、化学固定/稳定化、化学氧化以及联合修复等常见土壤物化治理技术进行了分析,探讨了各种工艺技术的性能及优缺点,旨在为我国土壤污染修复治理技术的选择提供参考。     

超声波提取-原子吸收光谱法测定油区土壤中重金属的含量

优化了超声波辅助提取土壤中重金属的条件,建立了原子吸收光谱法测定土壤中Cd、Cr、Cu、Ni、Pb和Zn的方法.各元素的线性关系良好(r=0.9991～0.9998),检出限为0.002～0.013 mg/L,相对标准偏差(RSD)为1.4％～5.8％,加标回收率为92.0％～110％.在优化的超声提取条件下分析标准物质GBW07439,并与湿法消解结果相比较,两种方法的测定值与参考值均相符,但超声提取法速度较快、安全性较好、污染小、试剂消耗少、残渣少.利用该方法分析辽河油田周边土壤中重金属含量,采用单因子污染指数法和内梅罗综合污染指数法评价了土壤受重金属污染的程度.     

污染土壤的物化修复治理技术

污染土壤的修复治理过程中,物化技术以其快速高效的特点成为国内外研究的热点。本文通过对工程措施、玻璃化技术、热修复、电动力修复、光化学降解、化学淋洗、化学固定/稳定化、化学氧化以及联合修复等常见土壤物化治理技术的分析,探讨了各种工艺技术的性能及优缺点,旨在为我国土壤污染修复治理技术的选择提供参考。     

农用地重金属污染现状及修复方法

土壤是农业生产的基础,随着社会的进步和经济的高速发展,越来越多的污染物排入土壤,其中重金属所占的比例逐渐增大,成为土壤治理的主要对象。农用地重金属污染不仅会导致作物产量降低,而且重金属会随着食物链在人体内积累,对人体产生极大的危害,因此重金属污染修复迫在眉睫。文章综述了农用地重金属污染现状、来源以及各种修复技术,分析了不同修复技术的优势及不足,为运用联合修复技术控制农用地重金属污染提供一定的借鉴与思路。     

Ornamental Plant Efficiency for Heavy Metals Phytoextraction from Contaminated Soils Amended with Organic Materials

Accumulation of heavy metals (HMs) by ornamental plants (OPs) from contaminated agriculture soils is a unique technique that can efficiently reduce the metal load in the food chain. Amaranthus tricolor L. has attractive characteristics acquiring a higher growth rate and large biomass when grown at heavy metal contaminated soils. Site-specific detailed information is not available on the use of A. tricolor plant in metal phytoremediation from the polluted sites. The study aimed to enhance the uptake of HMs (Pb, Zn, and Cu) via amending poultry litter extract (PLE), vinasse sugarcane (VSC), and humic acid (HA) as natural mobilized organic materials compared to ethylene diamine tetraacetic acid (EDTA), as a common mobilized chemical agent by A. tricolor plant. The studied soils collected from Helwan, El-Gabal El-Asfar (Cairo Governorate), Arab El-Madabeg (Assiut Governorate), Egypt, and study have been conducted under pot condition. Our results revealed all organic materials in all studied soils, except EDTA in EL-Gabal El-Asfar soil, significantly increased the dry weight of the A. tricolor plant compared to the control treatment. The uptake of Pb and Zn significantly (p > 0.05) increased due to applying all organic materials to the studied soils. HA application caused the highest uptake as shown in Pb concentration by more than 5 times in Helwan soil and EDTA by 65% in El-Gabal El-Asfar soil while VSC increased it by 110% in El-Madabeg soil. Also, an increase in Zn concentration due to EDTA application was 58, 42, and 56% for Helwan, El-Gabal El-Asfar, and El-Madabeg soil, respectively. In all studied soils, the application of organic materials increased the remediation factor (RF) than the control. El-Madabeg soil treated with vinasse sugarcane gave the highest RF values; 6.40, 3.26, and 4.02% for Pb, Zn, and Cu, respectively, than the control. Thus, we identified A. tricolor as a successful ornamental candidate that, along with organic mobilization amendments, most efficiently develop soil health, reduce metal toxicity, and recommend remediation of heavy metal-contaminated soils. Additionally, long-term application of organic mobilization amendments and continued growth of A. tricolor under field conditions could be recommended for future directions to confirm the results.     

铀污染土壤的植物修复研究

核工业的发展, 导致重金属铀的排放和扩散, 造成了地表土壤的污染, 对社会和环境造成了很大的影响, 如何修复被铀污染的土壤成为了一个难题, 近年发展起来的植物修复技术以其成本低廉、安全、环保的特点成为修复被铀污染的土壤的新选择. 寻找理想的超富集植物是这一技术的基础和关键之所在, 通过实验模拟铀污染土壤(土壤中铀的浓度为1.00×10² mg•kg^－1), 选取分属8种科目的19种植物去修复, 选出了几种对铀的修复性能较好的本土植物, 实验表明四季香油麦菜的生物累积系数(Bioconcentration factors, BFS)和生物转移系数(Translocation factors, TFS)都大于3, 且地上部分铀的富集浓度高达1.67×10³ mg•kg^－1, 可以作为铀的超富集植物, 四川沿阶草、四季豆、扁竹兰、吊兰几种本土植物对铀污染的土壤具有潜在的修复能力, 借助于基因工程、联合修复或添加土壤改良剂有望使其转变为对铀的超积累植物.     

环境化学开放性实验设计:重金属污染土壤的化学淋洗*

介绍了一个开放性环境化学实验。该实验以被重金属污染的土壤为研究对象,分别使用稀盐酸、乙二胺四乙酸、氯化钙为淋洗剂,对其进行化学淋洗修复。通过电感耦合等离子体光谱仪分析比较修复前后土壤中铅、镉的含量,用以帮助学生加深理解配合/螯合作用、酸-碱反应、离子交换反应、胶体的性质、土壤重金属形态、土壤性质与组成等相关环境化学知识。实验所用的土壤样品由学生自选,不同类型土壤的理化性质影响淋洗效果,从而增加了实验结果的不确定性。本实验贴近学科前沿且联系工程实际,可激发学生独立思考和探索精神,提高学生的科研能力与解决复杂问题的能力。     

六种微山湖湿地植物重金属富集能力分析

利用火焰原子吸收分光光度法测定了微山湖6种湿地植物（拉拉秧、黄花、红柳、芦苇、香蒲、三菱草）中重金属Cu、Pb、Zn、Cd的含量,并探讨了湿地植物对水环境中重金属的吸收与富集能力以及土壤和水体的绿色植物修复技术。结果表明,这些植物中Zn、Cu、Pb含量较高,黄花对Cu富集能力最强,香蒲对Pb富集能力最强,红柳对Zn富集能力最强。     

微波场协同提取紫背天葵色素的研究

研究了微波提取紫背天葵(Begonia fimbristipula Hance)色素的新工艺,并确定了最佳工艺条件：提取剂为φ(C2H5OH)=60％的乙醇,提取剂与原料用量比为1：60,微波功率为648W,提取时间为200s,提取次数为2次。最佳工艺条件下的色素提取率为96．8％,产率为9．98％,色价E(1％,526m)为10．5,产品pH值为6．5。与溶剂浸提法相比,微波法提取紫背天葵色素的每次提取时间由24h减少到200s,提取率从95．9％增加到96．8％。     

Chemical Fractionations of Lead and Zinc in the Contaminated Soil Amended with the Blended Biochar/Apatite

Heavy metal contamination in agricultural land is an alarming issue in Vietnam. It is necessary to develop suitable remediation methods for environmental and farming purposes. The present study investigated the effectiveness of using peanut shell-derived biochar to remediate the two heavy metals Zn and Pb in laboratory soil assays following Tessier’s sequential extraction procedure. The concentration of heavy metals was analyzed using Inductively coupled plasma mass spectrometry (ICP-MS). This study also compared the effectiveness of the blend of biochar and apatite applied and the mere biochar amendment on the chemical fractions of Pb and Zn in the contaminated agricultural soil. Results have shown that the investigated soil was extremely polluted by Pb (3047.8 mg kg⁻¹) and Zn (2034.3 mg kg⁻¹). In addition, the pH, organic carbon, and electrical conductivity values of amended soil samples increased with the increase in the amendment’s ratios. The distribution of heavy metals in soil samples was in the descending order of carbonate fraction (F2) > residue fraction (F5) > exchangeable fraction (F1) > Fe/Mn oxide fraction (F3) > organic fraction (F4) for Pb and F5 ≈ F2 > F1 > F3 > F4 for Zn. The peanut shell-derived biochar produced at 400 °C and 600 °C amended at a 10% ratio (PB4:10 and PB6:10) could significantly reduce the exchangeable fraction Zn from 424.82 mg kg⁻¹ to 277.69 mg kg⁻¹ and 302.89 mg kg⁻¹, respectively, and Pb from 495.77 mg kg⁻¹ to 234.55 mg kg⁻¹ and 275.15 mg kg⁻¹, respectively, and immobilize them in soil. Amending the biochar and apatite combination increased the soil pH, then produced a highly negative charge on the soil surface and facilitated Pb and Zn adsorption. This study shows that the amendment of biochar and biochar blended with apatite could stabilize Pb and Zn fractions, indicating the potential of these amendments to remediate Pb and Zn in contaminated soil.     

Identification and structural characterisation of triterpene saponins from the root of Ardisia mamillata Hance by HPLC-ESI-QTOF-MS/MS

Triterpene saponins in medicinal plants attract scientific attentions for their structural diversity and significant bioactivities. In this work, a high-performance liquid chromatography coupled to electrospray ionisation and quadrupole time-of-flight mass spectrometry (HPLC-ESI-QTOF-MS/MS) method is used to rapidly separate and identify triterpene saponins from the extract of Ardisia mamillata Hance (AMH). In the full scan mass spectrum, the accurate determination of molecular formula is obtained by the predominant ion [M + HCOO]^? in negative ion mode. As a result, 30 triterpene saponins are identified or tentatively identified in the plant extract. Of these, 17 triterpene saponins are new compounds. In conclusion, the HPLC-ESI-QTOF-MS/MS is an efficient technique to separate and identify triterpene saponins in complex matrices of medicinal plant.