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Phytoremediation of cadmium improved with the high production of endogenous phenolics and free proline contents in Parthenium hysterophorus plant treated exogenously with plant growth regulator and chelating agent Full text
2015
Ali, Nasir | Hadi, Fazal
Pot experiments were conducted to evaluate the effects of gibberellic acid (GA₃) and ethylenediaminetetraacetic acid (EDTA) on growth parameters, cadmium (Cd) phytoextraction, total phenolics, free proline and chlorophyll content of Parthenium hysterophorus plant grown in Cd-contaminated (100 mg/kg) soil. GA₃ was applied as foliar spray (10⁻², 10⁻⁴ and 10⁻⁶ M) while EDTA (40 mg/kg soil) was added to soil as single and in split doses. Results showed decrease in growth parameters due to Cd stress but P. hysterophorus plant demonstrated Cd hyperaccumulator potential based on bioconcentration factor (BCF). Lower concentration of GA₃ (10⁻⁶ M) showed highest significant increase in the growth parameters while Cd concentration, accumulation (1.97 ± 0.11 mg/DBM) and bioconcentration (9.75 ± 0.34) was significantly higher in the treatment T11 (GA₃ 10⁻² + split doses of EDTA). Cadmium significantly increased the root free proline while total phenolic concentration was significantly high in all parts of the plant. Chlorophyll contents were significantly reduced by Cd. GA₃ showed significant increase in phenolic and chlorophyll contents in plant. Cadmium accumulation in plant tissues showed positive correlation with free proline (R ² = 0.527, R ² = 0.630) and total phenolics (R ² = 0.554, R ² = 0.723) in roots and leaves, respectively. Cd contents negatively correlated with biomass, chlorophyll and total water contents. Proline and phenolic contents showed positive correlation with dry biomass of plant. These findings suggest further investigation to study the role of endogenous phenolics and proline in heavy metal phytoremediation.
Show more [+] Less [-]Andra Environmental Specimen Bank: archiving the environmental chemical quality for long-term monitoring Full text
2015
Leclerc, Elisabeth | d’Arbaumont, Maëlle | Verron, Jean-Patrick | Goldstein, Céline | Cesar, Frédérique | Dewonck, Sarah
Andra Environmental Specimen Bank (ESB) was established in 2010 as a part of the Perennial Observatory of the Environment (OPE), ongoing Long-Term Environmental Research Monitoring and Testing System located next to the Underground Research Laboratory (URL) at Bure, Meuse/Haute-Marne, France. The URL is used to study the deep geological disposal of high and intermediate level radioactive waste. Andra ESB is designed to archive during at least 100 years samples collected to define the initial state of environmental quality of the local area before the construction of industrial facilities and to ensure the traceability of long-term series of samples collected by the OPE (http://www.andra.fr/ope), using safe long-term conservation practices. Samples archived in the bank include some local food chain products (milk, cheese, honey, cereals, grass, cherry plum…) and specimen usually archived internationally to monitor the environmental quality (soil, sediment, water, fish, tree leaves, wild life, etc.). Regarding the different samples and analytical issues, three conservation modalities and facilities were designed: dry conservation under controlled temperature and humidity, cryopreservation in liquid nitrogen (LN2) vapor phase freezers (−150 °C) and in deep-freezing at −80 °C for temporary storage and raw samples before preparation. Andra ESB is equipped with a sample preparation clean room, certified ISO Class 5, dedicated to cryopreservation. This paper describes this first French experiment of long-term chemical quality monitoring and samples cryopreservation of different ecosystems and environmental compartments.
Show more [+] Less [-]Comparing the performance of geostatistical models with additional information from covariates for sewage plume characterization Full text
2015
Del Monego, Maurici | Ribeiro, Paulo Justiniano Jr | Ramos, Patricia
In this work, kriging with covariates is used to model and map the spatial distribution of salinity measurements gathered by an autonomous underwater vehicle in a sea outfall monitoring campaign aiming to distinguish the effluent plume from the receiving waters and characterize its spatial variability in the vicinity of the discharge. Four different geostatistical linear models for salinity were assumed, where the distance to diffuser, the west-east positioning, and the south-north positioning were used as covariates. Sample variograms were fitted by the Matèrn models using weighted least squares and maximum likelihood estimation methods as a way to detect eventual discrepancies. Typically, the maximum likelihood method estimated very low ranges which have limited the kriging process. So, at least for these data sets, weighted least squares showed to be the most appropriate estimation method for variogram fitting. The kriged maps show clearly the spatial variation of salinity, and it is possible to identify the effluent plume in the area studied. The results obtained show some guidelines for sewage monitoring if a geostatistical analysis of the data is in mind. It is important to treat properly the existence of anomalous values and to adopt a sampling strategy that includes transects parallel and perpendicular to the effluent dispersion.
Show more [+] Less [-]Sorption and desorption of Cr(VI) ions from water by biochars in different environmental conditions Full text
2015
Tytłak, Aleksandra | Oleszczuk, Patryk | Dobrowolski, Ryszard
In the present research, the potential of two biochars produced by the thermal decomposition of wheat straw (BCS) and wicker (BCW) for Cr(VI) ions removing from wastewater was investigated. The pH and the presence of chlorides and nitrates were also investigated. The Freundlich and Langmuir models were applied for the characterization of adsorption isotherms. The Langmuir model has better fitting of adsorption isotherms than the Freundlich model. The sorption process can be described by the pseudo second-order equation. The optimal adsorption capacities were obtained at pH 2 and were 24.6 and 23.6 mg/g for BCS and BCW, respectively. X-ray photoelectron spectroscopy (XPS) studies confirmed that Cr(III) ions were the most abundant chromium species on the biochars’ surface. The results indicated that the sorption mechanism of Cr(VI) on biochar involves anionic and cationic adsorption combined with Cr(VI) species reduction.
Show more [+] Less [-]Effect of inorganic amendments for in situ stabilization of cadmium in contaminated soils and its phyto-availability to wheat and rice under rotation Full text
2015
Rehman, Muhammad Zia-ur | Rizwan, Muhammad | Ghafoor, Abdul | Naeem, Asif | Ali, Shafaqat | Ṣābir, Muḥammad | Qayyum, Muhammad Farooq
Cadmium (Cd) toxicity is a widespread problem in crops grown on contaminated soils, and little information is available on the role of inorganic amendments in Cd immobilization, uptake, and tolerance in crops especially under filed conditions. The effect of three amendments, monoammonium phosphate (MAP), gypsum, and elemental sulfur (S), on Cd immobilization in soil and uptake in wheat and rice plants, under rotation, were investigated under field conditions receiving raw city effluent since >20 years and contaminated with Cd. Three levels of each treatment, 0.2, 0.4, and 0.8 % by weight, were applied at the start of the experiment, and wheat was sown in the field. After wheat harvesting, rice was sown in the same field without application of amendments. Both crops were harvested at physiological maturity, and data regarding grain yield, straw biomass, Cd concentrations, and uptake in grain and straw, and bioavailable Cd in soil and soil pH were recorded. Both MAP and gypsum application increased grain yield and biomass of wheat and rice, while S application did not increase the yield of both crops. MAP and gypsum amendments decreased gain and straw Cd concentrations and uptake in both crops, while S application increased Cd concentrations in these parts which were correlated with soil bioavailable Cd. We conclude that MAP and gypsum amendments could be used to decrease Cd uptake by plants receiving raw city effluents, and gypsum might be a better amendment for in situ immobilization of Cd due to its low cost and frequent availability.
Show more [+] Less [-]Development of a standard protocol for monitoring trace elements in continental waters with moss bags: inter- and intraspecific differences Full text
2015
Cesa, Mattia | Bertossi, Alberto | Cherubini, Giovanni | Gava, Emanuele | Mazzilis, Denis | Piccoli, Elisa | Verardo, Pierluigi | Nimis, P. L.
This paper is a contribution for validating a standard method for trace element monitoring based on transplants and analysis of aquatic bryophytes, in the framework of the EC Directive 2000/60. It presents the results of an experiment carried out to assess significant differences in the amount and variability of As, Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in three moss species (Cinclidotus aquaticus, Fontinalis antipyretica, Platyhypnidium riparioides) and two different parts of the moss (whole plant vs apical tips). Mosses were caged in bags made of a plastic net and transplanted for 2 weeks to an irrigation canal impacted by a waste water treatment plant. Trace element concentrations were measured by inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS) before and after exposure to the experimental and control sites in five samples. Enrichment factors >>2 were found for Cu, Ni, Mn, Pb and Zn in all moss species, lower in C. aquaticus, intermediate in F. antipyretica and higher in P. riparioides (the species we recommend to use). The analysis of apical tips after exposure instead of the whole plant led to (I) lower concentrations of As, Co, Cr, Fe and Zn in C. aquaticus (−7 to −30 %) and of Fe and Pb (−13, −18 %) in P. riparioides, (II) higher concentrations of Cu, Ni and Zn (+14 to +18 %) in P. riparioides, while (III) no significant difference (p > 0.05) in F. antipyretica. Data variability after exposure was generally lower in apical tips, especially in C. aquaticus and in F. antipyretica, less in P. riparioides. In the aim of standardizing the moss-bag technique, the analysis of apical tips is recommended.
Show more [+] Less [-]Coal fly ash as a resource for rare earth elements Full text
2015
Franus, Wojciech | Wiatros-Motyka, Małgorzata M. | Wdowin, Magdalena
Rare earth elements (REE) have been recognised as critical raw materials, crucial for many clean technologies. As the gap between their global demand and supply increases, the search for their alternative resources becomes more and more important, especially for the countries which depend highly on their import. Coal fly ash (CFA), which when not utilised is considered waste, has been regarded as the possible source of many elements, including REE. Due to the increase in the energy demand, CFA production is expected to grow, making research into the use of this material a necessity. As Poland is the second biggest coal consumer in the European Union, the authors have studied different coal fly ashes from ten Polish power plants for their rare earth element content. All the fly ashes have a broadly similar distribution of rear earth elements, with light REE being dominant. Most of the samples have REE content relatively high and according to Seredin and Dai (Int J Coal Geol 94: 67–93, 2012) classification can be considered promising REE raw materials.
Show more [+] Less [-]The global move toward Internet shopping and its influence on pollution: an empirical analysis Full text
2015
Al-Mulali, Usama | Sheau-Ting, Low | Ozturk, Ilhan
This study investigates the influence of Internet retailing on carbon dioxide (CO₂) emission in 77 countries categorized into developed and developing countries during the period of 2000–2013. To realize the aims of the study, a model that represents pollution is established utilizing the panel two-stage least square (TSLS) and the generalized method of moments (GMM). The results for both regressions similarly indicated that GDP growth, electricity consumption, urbanization, and trade openness are the main factors that increase CO₂ emission in the investigated countries. Although the results show that Internet retailing reduces CO₂ emission in general, a disaggregation occurs between developed and developing countries whereby Internet retailing has a significant negative effect on CO₂ emission in the developed countries while it has no significant impact on CO₂ emission in the developing countries. From the outcome of this study, a number of policy implications are provided for the investigated countries.
Show more [+] Less [-]Study and health risk assessment of the occurrence of iron and manganese in groundwater at the terminal of the Xiangjiang River Full text
2015
Huang, Bin | Li, Zhongwu | Chen, Zhiliang | Chen, Guiqiu | Zhang, Chang | Huang, Jinquan | Nie, Xiaodong | Xiong, Weiping | Zeng, Guangming
The pollution of the surface water in the Xiangjiang watershed in China has received much attention, whereas the groundwater conditions in the area have long been ignored. This study investigates the occurrence of Fe and Mn in the groundwater of Chengxi Town located at the terminal of the Xiangjiang River. The study area was monitored for an entire year. Thereafter, the associated health risks were identified. Results showed that approximately 81 and 73 % of the measured samples exceeded the limits for Fe and Mn in Chinese drinking water, respectively. pH level was found to be negatively correlated with the concentrations of Fe and Mn in the groundwater in the study area. The occurrence of Fe in the groundwater showed significant seasonal fluctuations and was possibly affected by the change in environment conditions within the aquifer. By contrast, Mn remained relatively stable in most of the area during the whole year. Overall, no health threats for adults and children in the study area were determined according to the low health index values. Nevertheless, research attention and the implementation of relevant measures are needed for certain villages with exceptionally high Mn concentrations in the groundwater.
Show more [+] Less [-]Application of reverse dot blot hybridization to simultaneous detection and identification of harmful algae Full text
2015
Chen, Guo Fu | Zhang, Chun Yun | Wang, Yuan Yuan | Chen, Wen
Warning and monitoring projects of harmful algal blooms require simple and rapid methods for simultaneous and accurate detection and identification of causative algae present in the environmental samples. Here, reverse dot blot hybridization (RDBH) was employed to simultaneously detect several harmful algae by using five representative bloom-forming microalgae along the Chinese coast. A set of specific probes for RDBH were developed by PCR, cloning, and sequencing of the internal transcribed spacer (ITS), alignment analysis, and probe design. Each probe was oligo (dT)-tailed and spotted onto positively charged nylon membrane to make up a low-density oligonucleotide array. Universal primers designed within the conserved regions were used to amplify the ITS sequences by using genomic DNA of target as templates. The digoxigenin (Dig)-labeled PCR products were denatured and then hybridized to the oligonucleotide array. The array produced a unique hybridization pattern for each target species differentiating them from each other. The preparations of oligonucleotide array and hybridization conditions were optimized. The developed RDBH demonstrated a detection limit up to 10 cells. The detection performance of RDBH was relatively stable and not affected by non-target species and the fixation time of target species over at least 30 days. The RDBH could recover all the target species from the simulated field samples and target species confirmed by the subsequent microscopy examination in the environmental samples. These results indicate that RDBH can be a new technical platform for parallel discrimination of harmful algae and is promising for environmental monitoring of these microorganisms.
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