重金属污染土壤的植物修复效果评价方法研究进展

从植物修复后土壤-植物系统重金属含量、重金属形态变化、土壤理化特征变化、动植物生长状况、土壤微生物生态响应和修复后风险再评价等方面系统归纳了现有的关于土壤重金属污染植物修复的效果评价方法。在此基础上,就当前研究中存在的问题进行了梳理,并对未来的发展方向进行了展望,以期为重金属污染土壤的修复提供依据。     

钝化剂结合农艺调控修复在云南省某农田土壤修复中的效果分析

选择云南某重金属复合型污染农田为对象,研究了钝化剂结合农艺调控修复方法的效果。根据修复工程前后土壤、浸出液、地表水及地下水的监测分析对比结果显示,农田内源污染得到了有效的控制,但对于多金属复合型污染,修复治理较为困难,需要多种钝化剂分期实施才能达到修复效果,因此应结合经济效益及环境影响,科学制定修复目标及方案。     

重金属-石油烃复合污染土壤植物修复技术研究

综述了重金属、石油烃及重金属-石油烃复合污染的危害,分析总结了土壤重金属-石油烃复合污染植物修复技术的原理、适用范围、优缺点及应用,旨在为重金属-石油烃复合污染土壤植物修复提供科学参考。     

腐植酸对固废拆解地重金属污染土壤修复效果的研究

探讨了腐植酸对重金属污染土壤的修复效果。在固体废弃物拆解地重金属污染土壤中加入不同用量的滩涂泥提取的腐植酸,测定土壤中水溶态和有效态重金属Cu、Zn、Pb、Ni的含量。     

重金属污染土壤的植物修复研究进展

土壤污染是全球面临的一个亟待解决的环境问题。近年来,植物修复技术迅速发展为主要用于清除土壤重金属污染的生态技术。文章介绍了土壤重金属污染的特性、危害及其治理方法。重点介绍了植物修复技术,并探讨了今后植物修复技术的发展前景。     

Use of brassica plants in the phytoremediation and biofumigation processes

In recent decades, serious contamination of soils by heavy metals has been reported. It is therefore a matter of urgency to develop a new and efficient technology for removing contaminants from soil. Another aspect to this problem is that environmental pollution decreases the biological quality of soil, which is why pesticides and fertilizers are being used in ever-larger quantities. The environmentally friendly solutions to these problems are phytoremediation, which is a technology that cleanses the soil of heavy metals, and biofumigation, a process that helps to protect crops using natural plant compounds. So far, these methods have only been used separately; however, research on a technology that combines them both using white cabbage has been carried out.     

Effect of Heavy Metals in Plants of the Genus Brassica

Several species from the Brassica genus are very important agricultural crops in different parts of the world and are also known to be heavy metal accumulators. There have been a large number of studies regarding the tolerance, uptake and defense mechanism in several of these species, notably Brassica juncea and B. napus, against the stress induced by heavy metals. Numerous studies have also been published about the capacity of these species to be used for phytoremediation purposes but with mixed results. This review will focus on the latest developments in the study of the uptake capacity, oxidative damage and biochemical and physiological tolerance and defense mechanisms to heavy metal toxicity on six economically important species: B. juncea, B. napus, B. oleracea, B. carinata, B. rapa and B. nigra.     

Wastewater Treatment by Chemically Activated Carbons from Giant Reed: Effect of the Activation Atmosphere on Properties and Adsorptive Behavior

Abstract

Uptake of nickel and benzene from dilute single‐solute solutions, mimicking wastewater with low concentrations of heavy metals or volatile organic compounds, was examined using activated carbons with similar good surface properties (BET surface area of ≈1100 m²/g). They were developed through H₃PO₄ acid activation of giant reed (Arundo donax L.) under flowing air or N₂. The carbons obtained in air proved more effective to capture Ni(II) ions under pre‐established equilibrium conditions. Inversely, the N₂‐derived carbons exhibited a better ability for benzene adsorption. The behavior was related to the smaller total content of acidic/polar surface oxygen functionalities of the carbons developed under N₂ (1.9 meq/g), compared to that of the air‐derived ones (3.3 meq/g). Two‐, three‐parameter models described properly the isotherms, predicting similar maximum adsorption capacities (X_m ) for the investigated systems. The X_m parameter in the Langmuir's model was 0.44 mmol/g for the adsorption of Ni(II) ions on the air‐derived carbons, and 0.45 mmol/g for benzene adsorption on those obtained in N₂. Present results highlight the relevance of the surface chemistry developed upon activation to optimize the performance of activated carbons for wastewater treatment according to the pollutants' nature.     

活化方法对煤渣粉活化效果的影响

为寻找出煤渣的最佳活化方法,提升煤渣的利用价值,实现煤渣的资源化利用。对南昌火电厂的煤渣进行了机械活化后,对其进行化学激发,随后分别对煤渣粉和掺煤渣粉水泥砂浆进行了微观测试和力学试验。试验结果表明:当研磨时间不足60min时,煤渣粉的细度和活性随着机械研磨的时间延长而显著增长,当研磨时间超过60min后,其随时间延长而缓慢增长;当硫酸钠掺量为1.5%(硫酸钠/(水泥+煤渣粉+硫酸钠的总质量))时效果最佳。因此,该煤渣的最佳活化方法是机械研磨60min后,过筛,加入占胶凝材料总质量1.5%的硫酸钠。     

纤维素的活化方法研究进展

纤维素具有较强的分子内和分子间氢键,制约了纤维素的应用。为了提高纤维素的反应活性和可及度,需要对其进行活化处理。从化学活化、物理活化和物理-化学联合活化3方面综述了纤维素活化方法的研究进展,阐明了各种活化方法的作用机理,并对近期纤维素活化处理的研究成果进行了总结,在实际应用中应按不同的工艺需要选择不同的活化方法。     

腐植酸在土壤修复中的作用

目前,腐植酸对污染土壤的修复作用已经引起了人们的广泛关注。本文在介绍了腐植酸来源及其结构特点的基础上,论述了腐植酸在土壤改良、重金属污染及有毒有机污染物污染土壤修复等方面的作用。其中,腐植酸对土壤的改良作用主要包括改良土壤结构、改良盐碱地以及提高土壤肥力等;腐植酸对重金属和有毒有机污染物污染土壤的修复作用主要包括腐植酸对重金属和有机物的吸附沉淀作用、氧化还原作用以及腐植酸能够促进土壤微生物对有机污染物的降解等。最后,讨论了腐植酸在土壤修复中需要进一步加强研究的方面,为腐植酸在土壤修复中的应用提供重要参考。     

Use of elemental sulphur to enhance a cadmium solubilization and its vegetative removal from contaminated soil

To a soil artificially contaminated with cadmium, orthorhombic sulphur flower and a hydrophillic microbially produced elemental sulphur were added to induce the soil acidification. The soil was incubated in pots under opensky conditions. pH, sulphate, and cadmium solubility were recorded in time. Soil acidification with microbially produced sulphur proceeded without any delay and at considerably higher rates, compared to the sulphur flower. Cadmium solubilization was solely controlled by the soil pH during the experiments. Similar experiments with cultivation of common mustard (Sinapis alba, cultivar JARA) were performed, evaluating both changes of cadmium solubilization and uptake by biomass. Cadmium concentration in shoots increased with decreasing pH. However, biomass was negatively affected by the decreasing pH. Combining these two effects, a pH-optimum for maximum cadmium removal from the soil by plants was found at pH=5–5.5.