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Gert E Dudel - One of the best experts on this subject based on the ideXlab platform.
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nitrogen species coupled with transpiration enhance fe plaque assisted aquatic uranium removal via Rhizofiltration of phragmites australis trin ex steud
Journal of Environmental Radioactivity, 2018Co-Authors: Weiqing Wang, Gert E DudelAbstract:Abstract The influences of N species and transpiration on the Fe plaque (IP) formation and related aquatic U Rhizofiltration had not revealed yet, especially when these factors were co-existed. It was evaluated in a mesocosm experiment in the condition of respective ammonium (NH4+)/nitrate (NO3−) cultivation of Phragmites australis Trin ex Steud. coupled with different transpiration rates (TRs). The results suggested that the enhanced transpiration of P. australis improved the aquatic U Rhizofiltration in both NO3− and NH4+ rich milieus. However, the NO3− dependent oxidizing milieu restricted aquatic U uptake by the root of P. australis (up to 47.6 ± 1.8 mg kg−1 under high TR) via IP assisted Rhizofiltration. The high aquatic U availability and limited IP formation in NO3− rich milieu benefited the U retention within root tissue. On the contrary, the aquatic U Rhizofiltration (up to 62.1 ± 1.0 mg kg−1 under high TR) was enhanced under NH4+ dependent reductive milieu. It was mainly contributed by U retention within IP. The area related U accumulation in different N species cultured roots was enhanced but did not significantly different under higher TR condition. The result suggested that the supplied NH4+ coupled with enhanced transpiration was supposed to be more optimized option for IP assisted aquatic U Rhizofiltration via P. australis.
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fe plaque related aquatic uranium retention via Rhizofiltration along a redox state gradient in a natural phragmites australis trin ex steud wetland
Environmental Science and Pollution Research, 2017Co-Authors: Weiqing Wang, Gert E DudelAbstract:Studies have revealed that the Rhizofiltration is a feasible plant-based technology for aquatic metal/metalloid removal. However, the performance of aquatic U retention via Rhizofiltration has not been fully revealed yet. In this study, a field investigation was conducted in a Phragmites australis Trin ex Steud. dominated wetland to estimate the efficiency of Fe plaque (IP)-assisted U Rhizofiltration, with redox-state gradient (−179 to 220 mV) and low aquatic U level (66.7 to 92.0 μg l−1). The U concentrations were determined in soil, root, and aboveground biomass of P. australis. The IP on root surface was extracted via DCB extraction procedure. The bio-concentration factor (BCF) was applied to evaluate the aquatic U transfer capacity from root to above ground biomass of P. australis. The result suggested that root of P. australis was highly effective for aquatic U uptake via Rhizofiltration (BCF 1025 to 1556). It also benefited the real U accumulation in aboveground biomass of P. australis (up to 0.4 mg m−2) and related plant-water-soil U recycling. The IP and associated microbial community in rhizosphere was effective mediator for aquatic U retention on root surface (BCF 1162 to 847). The IP-assisted aquatic U Rhizofiltration was significantly promoted in relatively reductive environment. It was benefited by the enhanced root uptake of Fe due to lower oxidizers (e.g., DO and NO3 −) availability. On the other hand, the competitive adsorption effect from co-existing IP-affinitive elements (e.g., As) also possibly impaired the real capacity of IP-assisted aquatic U Rhizofiltration via P. australis.
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Rhizofiltration of u by plant root surfaces in a tailing wetland
2015Co-Authors: Weiquing Q Wang, Carsten Brackhage, Ernst Bauker, Gert E DudelAbstract:It is well known that element transfer into plant shoots is highly variable and often very low in comparison with the accumulation in roots. On the other side, the role of Fe plaque on metalloid (P, As) and heavy metal stabilization on root surfaces has been widely researched on. In a reed dominated wetland along a flow gradient of seepage water plant and related water samples were taken to determine the relation between Fe plaque formation and U immobilization on the root surface of common reed (Phragmites australis TRIN. ex Steudt.). Fe plaques were observed in all sampling sites with a significant increase from near mine wa-ter inflow (Fe: 5449 mg·kg-1) to the near outlet (Fe: 16189 mg·kg-1), while an average of 87.1 % U was found fixed on root surfaces. The result indicated that an enhanced Fe plaque formation in the aeration zone of mine water inflow may inhibit more U from root inner ad- and absorption (accumulation) and/or competition with other elements (e.g. As). Both the increase of Fe plaque and the related root surface U coating is associated with a decreased redox potential in the surrounding interstitial water indicating that a reducing environment induced by organic matter decay (plant litter) could be an important factor. However, EDAX analysis showed that the U complex forming particles were not tightly adhered to the root surface but surround the root loosely. U is accumulated only to a small ex-tent within roots (Rhizofiltration in sensu strictu). This is different to other metal-oids (like As) and heavy elements (ions) which fully bind to root surfaces and in-side the rhizodermis.
Minjune Yang - One of the best experts on this subject based on the ideXlab platform.
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uranium Rhizofiltration by lactuca sativa brassica campestris l raphanus sativus l oenanthe javanica under different hydroponic conditions
Minerals, 2020Co-Authors: Yikyeong Han, Minhee Lee, Juyeon Lee, Changmin Kim, Jin Young Park, Minjune YangAbstract:Rhizofiltration experiments were conducted using uranium-contaminated groundwater and lettuce (Lactuca sativa), Chinese cabbage (Brassica campestris L.), radish (Raphanus sativus L.), and buttercup (Oenanthe javanica), which are commonly grown and consumed in South Korea. The results of the Rhizofiltration experiments with artificial solutions with different initial uranium concentrations (18, 32, 84, 116, 173, and 263 μg/L) show that the uranium accumulation and bioconcentration factor (BCF) of plant roots increase with increasing uranium concentration in the groundwater. Among the four plants, the uranium concentration in the roots of Raphanus sativus L. is 1215.8 μg/g dry weight, with a maximum BCF value of 2692.7. The BCF value of the artificial solutions with various pH values (pH 3, 5, 7, and 9) is the highest under acidic conditions (pH 3) for all four plants. The uranium BCF values based on different hydroponic conditions range from 170.5 to 11580.3 and the results are comparable with those of other studies using similar methods; the highest BCF value was determined for Brassica campestris L. at pH 3. The BCF values of Raphanus sativus L. after the Rhizofiltration experiments with genuine groundwater contaminated with uranium are the highest among the four species; that is, 1684.7 and 1700.1 in Oesam-dong and Bugokdong groundwater samples with uranium concentrations of 83 and 173 μg/L, respectively. The results of the scanning electron microscope/electron dispersive X-ray spectroscope analyses show that uranium in contaminated groundwater is adsorbed as a solid phase on the root surface. These results demonstrate that Raphanus sativus L. has a high tolerance to high concentrations of uranium and low pH conditions and a remarkable potential for uranium accumulation.
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uranium and cesium accumulation in bean phaseolus vulgaris l var vulgaris and its potential for uranium Rhizofiltration
Journal of Environmental Radioactivity, 2015Co-Authors: Minjune Yang, James W Jawitz, Minhee LeeAbstract:Laboratory scale Rhizofiltration experiments were performed to investigate uranium and cesium accumulation in bean (Phaseolus vulgaris L. var. vulgaris) and its potential for treatment of uranium contaminated groundwater. During 72 h of Rhizofiltration, the roots of the bean accumulated uranium and cesium to concentrations 317-1019 times above the initial concentrations, which ranged from 100 to 700 μg l(-1) in artificially contaminated solutions. When the pH of the solution was adjusted to 3, the ability to accumulate uranium was 1.6 times higher than it was for solutions of pH 7 and pH 9. With an initial uranium concentration of 240 μg l(-1) in genuine groundwater at pH 5, the bean reduced the uranium concentration by 90.2% (to 23.6 μg l(-1)) within 12 h and by 98.9% (to 2.8 μg l(-1)) within 72 h. A laboratory scale continuous clean-up system reduced uranium concentrations from 240 μg l(-1) to below 10 μg l(-1) in 56 h; the whole uranium concentration in the bean roots during system operation was more than 2600 μg g(-1) on a dry weight basis. Using SEM and EDS analyses, the uranium removal in solution at pH 7 was determined based on adsorption and precipitation on the root surface in the form of insoluble uranium compounds. The present results demonstrate that the Rhizofiltration technique using beans efficiently removes uranium and cesium from groundwater as an eco-friendly and cost-effective method.
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Rhizofiltration using sunflower helianthus annuus l and bean phaseolus vulgaris l var vulgaris to remediate uranium contaminated groundwater
Journal of Hazardous Materials, 2010Co-Authors: Minjune YangAbstract:Abstract The uranium removal efficiencies of Rhizofiltration in the remediation of groundwater were investigated in lab-scale experiments. Sunflower (Helianthus annuus L.) and bean (Phaseolus vulgaris L. var. vulgaris) were cultivated and an artificially uranium contaminated solution and three genuine groundwater samples were used in the experiments. More than 80% of the initial uranium in solution and genuine groundwater, respectively, was removed within 24 h by using sunflower and the residual uranium concentration of the treated water was lower than 30 μg/L (USEPA drinking water limit). For bean, the uranium removal efficiency of the Rhizofiltration was roughly 60–80%. The maximum uranium removal via Rhizofiltration for the two plant cultivars occurred at pH 3–5 of solution and their uranium removal efficiencies exceeded 90%. The lab-scale continuous Rhizofiltration clean-up system delivered over 99% uranium removal efficiency, and the results of SEM and EDS analyses indicated that most uranium accumulated in the roots of plants. The present results suggested that the uranium removal capacity of two plants evaluated in the clean-up system was about 25 mg/kg of wet plant mass. Notably, the removal capacity of the root parts only was more than 500 mg/kg.
Weiqing Wang - One of the best experts on this subject based on the ideXlab platform.
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nitrogen species coupled with transpiration enhance fe plaque assisted aquatic uranium removal via Rhizofiltration of phragmites australis trin ex steud
Journal of Environmental Radioactivity, 2018Co-Authors: Weiqing Wang, Gert E DudelAbstract:Abstract The influences of N species and transpiration on the Fe plaque (IP) formation and related aquatic U Rhizofiltration had not revealed yet, especially when these factors were co-existed. It was evaluated in a mesocosm experiment in the condition of respective ammonium (NH4+)/nitrate (NO3−) cultivation of Phragmites australis Trin ex Steud. coupled with different transpiration rates (TRs). The results suggested that the enhanced transpiration of P. australis improved the aquatic U Rhizofiltration in both NO3− and NH4+ rich milieus. However, the NO3− dependent oxidizing milieu restricted aquatic U uptake by the root of P. australis (up to 47.6 ± 1.8 mg kg−1 under high TR) via IP assisted Rhizofiltration. The high aquatic U availability and limited IP formation in NO3− rich milieu benefited the U retention within root tissue. On the contrary, the aquatic U Rhizofiltration (up to 62.1 ± 1.0 mg kg−1 under high TR) was enhanced under NH4+ dependent reductive milieu. It was mainly contributed by U retention within IP. The area related U accumulation in different N species cultured roots was enhanced but did not significantly different under higher TR condition. The result suggested that the supplied NH4+ coupled with enhanced transpiration was supposed to be more optimized option for IP assisted aquatic U Rhizofiltration via P. australis.
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fe plaque related aquatic uranium retention via Rhizofiltration along a redox state gradient in a natural phragmites australis trin ex steud wetland
Environmental Science and Pollution Research, 2017Co-Authors: Weiqing Wang, Gert E DudelAbstract:Studies have revealed that the Rhizofiltration is a feasible plant-based technology for aquatic metal/metalloid removal. However, the performance of aquatic U retention via Rhizofiltration has not been fully revealed yet. In this study, a field investigation was conducted in a Phragmites australis Trin ex Steud. dominated wetland to estimate the efficiency of Fe plaque (IP)-assisted U Rhizofiltration, with redox-state gradient (−179 to 220 mV) and low aquatic U level (66.7 to 92.0 μg l−1). The U concentrations were determined in soil, root, and aboveground biomass of P. australis. The IP on root surface was extracted via DCB extraction procedure. The bio-concentration factor (BCF) was applied to evaluate the aquatic U transfer capacity from root to above ground biomass of P. australis. The result suggested that root of P. australis was highly effective for aquatic U uptake via Rhizofiltration (BCF 1025 to 1556). It also benefited the real U accumulation in aboveground biomass of P. australis (up to 0.4 mg m−2) and related plant-water-soil U recycling. The IP and associated microbial community in rhizosphere was effective mediator for aquatic U retention on root surface (BCF 1162 to 847). The IP-assisted aquatic U Rhizofiltration was significantly promoted in relatively reductive environment. It was benefited by the enhanced root uptake of Fe due to lower oxidizers (e.g., DO and NO3 −) availability. On the other hand, the competitive adsorption effect from co-existing IP-affinitive elements (e.g., As) also possibly impaired the real capacity of IP-assisted aquatic U Rhizofiltration via P. australis.
Minhee Lee - One of the best experts on this subject based on the ideXlab platform.
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uranium Rhizofiltration by lactuca sativa brassica campestris l raphanus sativus l oenanthe javanica under different hydroponic conditions
Minerals, 2020Co-Authors: Yikyeong Han, Minhee Lee, Juyeon Lee, Changmin Kim, Jin Young Park, Minjune YangAbstract:Rhizofiltration experiments were conducted using uranium-contaminated groundwater and lettuce (Lactuca sativa), Chinese cabbage (Brassica campestris L.), radish (Raphanus sativus L.), and buttercup (Oenanthe javanica), which are commonly grown and consumed in South Korea. The results of the Rhizofiltration experiments with artificial solutions with different initial uranium concentrations (18, 32, 84, 116, 173, and 263 μg/L) show that the uranium accumulation and bioconcentration factor (BCF) of plant roots increase with increasing uranium concentration in the groundwater. Among the four plants, the uranium concentration in the roots of Raphanus sativus L. is 1215.8 μg/g dry weight, with a maximum BCF value of 2692.7. The BCF value of the artificial solutions with various pH values (pH 3, 5, 7, and 9) is the highest under acidic conditions (pH 3) for all four plants. The uranium BCF values based on different hydroponic conditions range from 170.5 to 11580.3 and the results are comparable with those of other studies using similar methods; the highest BCF value was determined for Brassica campestris L. at pH 3. The BCF values of Raphanus sativus L. after the Rhizofiltration experiments with genuine groundwater contaminated with uranium are the highest among the four species; that is, 1684.7 and 1700.1 in Oesam-dong and Bugokdong groundwater samples with uranium concentrations of 83 and 173 μg/L, respectively. The results of the scanning electron microscope/electron dispersive X-ray spectroscope analyses show that uranium in contaminated groundwater is adsorbed as a solid phase on the root surface. These results demonstrate that Raphanus sativus L. has a high tolerance to high concentrations of uranium and low pH conditions and a remarkable potential for uranium accumulation.
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evaluation of Rhizofiltration for uranium removal with calculation of the removal capacity of raphanus sativus l
Journal of Soil and Groundwater Environment, 2015Co-Authors: Yikyeong Han, Minhee LeeAbstract:The uranium removal capacity of radish sprouts (Raphanus sativus L.) in groundwater was calculated on the basis of the amount of uranium accumulated in the radish sprouts rather than the concentration in solution, of which process was very limited in previous studies. Continuous Rhizofiltration clean-up system was designed to investigate the feasibility of radish sprouts, applying for uranium contaminated groundwater (U concentration: 110 μg/L) taken at Bugogdong, Busan. Six acrylic boxes (10 cm × 30 cm × 10 cm) were connected in a direct series for the continuous Rhizofiltration system and 200 g of radish sprouts cultivars was placed in each box. The groundwater was flushed through the system for 48 hours at the constant rate of 5 mL/min. The Rhizofiltration system was operated in the phytotron, of which conditions were at 25℃ temperature, 70% of relative humidity, 4,000 Lux illumination (16 hours/day) and 600 mg/L of CO2 concentration. While 14.4 L of contaminated groundwater was treated, the uranium removal efficiency of the radish sprouts (1,200 g in wet weight) was 77.2% and their removal capacities ranged at 152.1 μg/g-239.7 μg/g (the average: 210.8 μg/g), suggesting that the radish sprouts belong to the group of hyper-accumulation species. After the experiment, the sum of U amounts accumulated in radish sprouts and remained in groundwater was 1,472.2 μg and the uranium recovery ratio of this Rhizofiltration experiment was 92.9%. From the results, it was investigated that the radish sprouts can remove large amounts of uranium from contaminated groundwater in a short time (few days) because the fast growth rate and the high U accumulation adsorption capacity.
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uranium and cesium accumulation in bean phaseolus vulgaris l var vulgaris and its potential for uranium Rhizofiltration
Journal of Environmental Radioactivity, 2015Co-Authors: Minjune Yang, James W Jawitz, Minhee LeeAbstract:Laboratory scale Rhizofiltration experiments were performed to investigate uranium and cesium accumulation in bean (Phaseolus vulgaris L. var. vulgaris) and its potential for treatment of uranium contaminated groundwater. During 72 h of Rhizofiltration, the roots of the bean accumulated uranium and cesium to concentrations 317-1019 times above the initial concentrations, which ranged from 100 to 700 μg l(-1) in artificially contaminated solutions. When the pH of the solution was adjusted to 3, the ability to accumulate uranium was 1.6 times higher than it was for solutions of pH 7 and pH 9. With an initial uranium concentration of 240 μg l(-1) in genuine groundwater at pH 5, the bean reduced the uranium concentration by 90.2% (to 23.6 μg l(-1)) within 12 h and by 98.9% (to 2.8 μg l(-1)) within 72 h. A laboratory scale continuous clean-up system reduced uranium concentrations from 240 μg l(-1) to below 10 μg l(-1) in 56 h; the whole uranium concentration in the bean roots during system operation was more than 2600 μg g(-1) on a dry weight basis. Using SEM and EDS analyses, the uranium removal in solution at pH 7 was determined based on adsorption and precipitation on the root surface in the form of insoluble uranium compounds. The present results demonstrate that the Rhizofiltration technique using beans efficiently removes uranium and cesium from groundwater as an eco-friendly and cost-effective method.
M H Fulekar - One of the best experts on this subject based on the ideXlab platform.
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Rhizofiltration of heavy metals cadmium lead and zinc from fly ash leachates using water hyacinth eichhornia crassipes
International Journal of Environment, 2015Co-Authors: Amit Kumar Yadav, Bhawana Pathak, M H FulekarAbstract:Fly ashes are usually contaminated with toxic heavy metals. These metals are leaching out aftercontact with water during wet disposal system, thus polluting the soil, surface and groundwater. In the present study, a hydroponics experiment was conducted to examine the removalof heavy metals Cd, Pb and Zn by Eichhornia crassipes grown at various concentration of fly ash ranging from 10, 20 and 40 percent over a period of 30 days.After 30 days, the plants were separately harvested, dried and weighedfor biomass of the roots and shoots. The uptake of each metalwas studied in the root and shoot separately, to determine the bioaccumulation of metals in Eichhornia crasspies .The translocation factor was calculated to study the efficiency of the plants forbioaccumulation of each metal in roots and shoot. The results showed that maximum uptake of metals Cd, Pb and Zn by plantwasfoundat the higher concentration (40%) of fly ash.The metals uptake found was 99.16, 166.52 and 741.04 μg g-1 tissues in the roots, respectively and 33.46, 41.33 and 255.90 μgg-1 tissues in the shoots, respectively and successfullyremoved up to 78% of Cd, 82% of Pb and 70% of Zn.The maximum removal efficiency by plant for Cd, Pb and Zn at lower concentration (10%) of fly ash was 84%, 86% and 75%, respectively.The heavy metals accumulated more in roots than in the shoots by Eichhornia crassipes . The maximum bioconcentration factor and translocation factor value of Eichhornia crappies for Cd, Pb and Zn were calculated as 705.55, 705.55 and 614.51 and 41.86, 47.18 and 34.53 respectively. The high removal efficiencies of heavy metals Cd, Pb and Zn was find without toxic effect by this aquatic macrophyte, thisplant can be recommended for the actual treatment of fly ash leachatesin ash pond to clean up the aquatic environment. DOI: http://dx.doi.org/10.3126/ije.v4i1.12187 International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15, page : 179-196
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Rhizofiltration a green technology for remediation of heavy metals
2012Co-Authors: M H Fulekar, Bhawana PathakAbstract:With the growing industrial and developmental activ ities pollution of heavy metal has become a environmental problem. Though metals are natural constituent of nature, yet their excess presence may cause toxicity to the living world. Concerning alter natives, phytoremediation is an emerging technology for treating waste water. Rhizofiltration is a techn ique of utilizing plant roots to absorb, concentrat e, and precipitate toxic metals from concentrated ground w ater or polluted effluents. As such 400 plants that hyperaccumulate metals are reported. The present pa per highlights Rhizofiltration techniques, mechanism of Rhizofiltration, significance of Rhizofi ltration for remediation of heavy metals. Rhizofiltration is based on the potential of green p lants which can be used as green technology for remediation of heavy metals. Further, genetic engin eering can be adopted for enhancing potential of plants for Rhizofiltration.
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phytoremediation of heavy metals recent techniques
African Journal of Biotechnology, 2009Co-Authors: Chhotu D Jadia, M H FulekarAbstract:The current remediation technique of heavy metal from contaminated soil-water are expensive, time consuming and environmentally destructive. Unlike organic compounds, metals cannot degrade, and therefore effective cleanup requires their immobilization to reduce or remove toxicity. In recent years, scientists and engineers have started to generate cost effective technologies that include use of microorganisms/biomass or live plants to clean polluted areas. Phytoremediation is an emerging technology for cleaning up contaminated sites, which is cost effective, and has aesthetic advantages and long term applicability. It is best applied at sites with shallow contamination of organic, nutrient or metal pollutants that are amenable to one of the five applications; phytotransformation, rhizosphere bioremediation, phytostabilization, phytoextraction and Rhizofiltration. The technology involves efficient use of plants to remove, detoxify or immobilize environmental contaminants in a growth matrix (soil, water or sediments) through the natural, biological, chemical or physical activities or processes of the plants. A brief review on phytoremediation of heavy metals and its effect on plants have been compiled to provide a wide applicability of phytoremediation.
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Rhizofiltration of heavy metals from coal ash leachate
Asian Journal of Water Environment and Pollution, 2006Co-Authors: Madhura Karkhanis, Chotu Jadia, M H FulekarAbstract:Heavy metals are leaching out from coal ash in the aquatic environment causing environmental pollution. In the present study the removal of heavy metals from coal ash leachate in the aquatic environment has been studied by using the aquatic plants such as water hyacinth, duckweed and pistia. Rhizofiltration of heavy metals was carried out at varying concentrations of coal ash starting from 0, 5, 10, 20, 30 and 40 percent. Simultaneously the physicochemical parameters of leachate have been analyzed and studied to understand the leachability. Rhizofiltration has shown that pistia has high potential capacity of uptake of the heavy metals Zn, Cr, and Cu, and duckweed has also shown good potential for uptake of Zn, Cr, Cu next to Pistia. Rhizofiltration of Zn and Cu in case of water hyacinth was lower as compared to pistia and duckweed. This research shows that pistia/duckweed/water hyacinth can be good accumulators of heavy metals in aquatic environment.