Issues and challenges of reclaimed water usage: a case study of the dragon-shaped river in the Beijing Olympic Park

Increased use of reclaimed water could be one of the solutions to Beijing’s growing water shortage, particularly for non-potable (e.g. landscaping) purposes. The dragon-shaped river, a large artificial waterscape built on the site of the 2008 Beijing Olympic games, offers a useful case study of the issues and challenges attendant on wastewater reclamation and reuse. Of particular interest is the use of phytoremediation techniques for bioremediation of nutrient loads. This article presents the results of ongoing monitoring which indicate that phytoremediation is succeeding in preventing eutrophication, though some challenges, notably management of aquatic biomass, remain.     

Influence of salinity on lead and cadmium accumulation by the salt cedar (Tamarix smyrnensis Bunge)

BACKGROUND: The removal of heavy metals from polluted soils through the use of suitable plants has attracted much interest over recent decades. In this study Tamarix smyrnensis Bunge has been investigated for the characterization of its metal tolerance and ability to accumulate Pb and Cd, in order to evaluate its effectiveness as a cleanup tool for phytoextraction applications. For this purpose, two hydroponic experiments were performed, one with lead at concentration 100 ppm and a second with cadmium at concentration 5 ppm and at three different salt concentrations (0, 100, 200 mmol L^?1 NaCl). RESULTS: The experimental results showed that Pb and Cd accumulation in shoots ranged from 150–270 ppm and 7.5–42 ppm, respectively, and salinity was found to increase metal accumulation in shoots. However, the presence of high metal and salt concentrations affected negatively the health and finally the survival of the plants. CONCLUSION: T. smyrnensis is neither a Pb nor a Cd hyperaccumulator; however, metal accumulation levels in shoots considered together with its high biomass production suggest that it could be used for phytoextraction applications. Furthermore, salinity has a positive influence on Pb and Cd accumulation in harvestable parts of the plant when it remains in low concentrations. Copyright © 2009 Society of Chemical Industry     

螯合剂与AM真菌联合修复铀污染土壤

以典型铀矿山周边铀污染土壤为基础，选取铀矿周边植物五节芒为试验样本，分析螯合剂与AM真菌联合对植物生物量、铀富集量、土壤pH及营养元素的影响。结果表明，施加柠檬酸(CA)与接种摩西球囊霉菌(Glomus mosseae，Gm)对五节芒生长、铀富集存在不同程度的促进作用，以二者联合处理效果最明显。虽然施加柠檬酸会降低土壤的pH，但接种Gm与五节芒形成的菌根共生体系可以通过自身调节来适应酸性土壤环境；且有效促进了五节芒对矿质营养元素N、P、K的吸收。根际土与植物灰样扫描电镜图显示，联合处理组表面附着颗粒更大更密集，修复效果最佳。螯合剂与AM真菌联合处理植物，对于铀污染土壤能够起到有效的修复作用。     

Remediation of Oil Contaminated Media Using Organic Material Supplementation

With the fact that anthropogenic activities are inevitable, especially with the continuous use of fossil fuels and other sources of hydrocarbons, environmental pollution appears to be a recurring issue. However, nascent science and technologies try to identify and apply varied options that can remedy polluted sites, which include oil spill situations. The present review elucidates the remediation options on the event of oil spill/contamination with emphasis on the adoption of biological treatment (supplement addition and phytoremediation), and overview on the potential relevance of remediation via advances in nanotechnology. The associated negativities and cost tend to outweigh the advantages of both methods when sustainability is considered.     

石油污染的植物修复技术研究

植物修复是治理石油污染的重要方法。论文分析了植物修复石油污染的机理,深入研究了植物修复的影响因素及其规律,提出了可用于修复石油污染的典型植物,介绍了植物修复在环境处理中的工程应用。论文所做的工作为植物修复技术在石油污染治理中的广泛应用提供了参考。     

水环境生态修复国内外研究进展

我国的江河湖库水体污染主要包括氮、磷等营养物和有机物污染两方面。目前国际上采用的技术主要有物理方法、化学方法和生物一生态方法。本文从外源和内源两方面对目前国内外的生态修复方法加以阐述，分析了近年国内外的相关文献资料．从方法上总结了河流、湖泊等水体生态修复的研究进展，并比较了各自的优点及缺陷。     

矿区土壤重金属污染现状及对策

介绍了矿区土壤重金属污染的现状、污染特点、污染来源，同时提出了相应的治理对策，指出植物修复是一种有前途的土壤污染治理技术。     

浮床黑麦草去除富营养化水体总氮的试验研究

采用围隔浮床系统,研究了冬、春季节陆生黑麦草(Lolium multiflorm)对畜禽养殖富营养水体中主要营养元素氮的净化效应及动态过程。结果表明:浮床黑麦草在试验小区中生长良好,浮床黑麦草系统对富营养水体中的总氮具有明显的净化效果。当覆盖率分别为15%,30%,45%和60%时,水体中的TN分别减少了5.6mg/L,6.54 mg/L,5.42 mg/L及3.36 mg/L。覆盖率为30%时,TN的去除率最高,达到74.91%。对浮床黑麦草去除水体总氮的动态过程拟合表明,符合三次方程曲线。     

Phytotoxicity and fate of 1,1,2-trichloroethylene: a laboratory study

1,1,2-Trichloroethylene (TCE), a chlorinated organic contaminant, poses serious environmental concerns. A study was conducted to evaluate the phytotoxicity of TCE to a crop species and its fate in vermiculite. Growth bioassays were carried out using carrot (Daucus carota L.) as the test species. Three different concentrations, 0.25, 0.50, and 1 ppm were used to evaluate phytotoxicity of TCE. When added to petri plates with cotton pads, TCE did not have any effect on carrot seedling growth. However, when added to vermiculite, it significantly suppressed growth. Shoot growth was inhibited only at the 1 ppm concentration. Recovery experiments were carried out to study the fate of TCE in vermiculite. A significant decline in the percent recovery was observed with time. Interestingly, TCE additional peaks (unknown organic molecules) were detected with declining concentrations. The available chloride ion concentration in vermiculite containing 1 ppm of TCE for 24 hr was significantly higher compared to control.     

Differences in X-ray absorption due to cadmium treatment in Saponaria officinalis leaves

A method for detecting cadmium uptake in leaves of Saponaria officinalis doped with a solution of cadmium acetate is described. The technique based on the exposure of dried leaves to X-rays of a wavelength close to that of the metal K-edge could be useful for phytoremediation studies as it could reveal the bioaccumulation in plants due to the treatment either in vivo or in vitro with heavy metals. X-ray microradiography measurements are in agreement with those from peroxidase enzyme assay utilized to follow the oxidative damage induced by heavy metals. At present, as we will see in this report, microradiography has still poorer sensitivity in comparison with enzyme assay, but it has the advantage of being faster, not destructive, and usable even at very high doping levels, where the enzyme assay technique results are fully saturated. Further analysis of the optical density values could lead to a quantitative measurement of the heavy metal in the sample. Thus, the technology developed in this article could be useful for tracing the intake in phytoremediation studies.