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Zhou D, Li C, Huang M, Chen X, Xia Y, Huang Y. The metal release and transformation mechanisms of V-Ti magnetite tailings: Role of the alternate flooding and drying cycles and organic acids. CHEMOSPHERE 2024; 362:142709. [PMID: 38936491 DOI: 10.1016/j.chemosphere.2024.142709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 06/01/2024] [Accepted: 06/24/2024] [Indexed: 06/29/2024]
Abstract
V-Ti magnetite tailings (VTMTs) contain various heavy metals, such as Fe, Mn, V, Co, and Ni. The groundwater pollution caused by the tailing metal release has become a local environmental concern. Although studies have demonstrated the influence of alternate flooding and drying cycles (FDCs) on metal form and mobility in minerals, little was known about whether FDCs affect the metal release of VTMTs and the transformation of released metals. This study investigated the metal release kinetics of VTMTs and the metal transformation under FDCs in the absence and presence of acid rain (sulfuric and nitric acids) and bio-secreted organic acids (acetic, oxalic, and citric acids). The results showed that FDCs promoted metal release whether or not acids were present. The maximum released concentrations of V, Mn, Fe, Co, and Ni were as high as 78.63 mg L-1,1.47 mg L-1, 67.96 μg L-1, 1.34 mg L-1, and 0.80 mg L-1, respectively, under FDCs and citric acids. FDCs enhanced the tailing metal release by increasing the metal labile fraction proportion. However, the concentrations of released Fe, Mn, V, Co, and Ni all gradually decreased due to their (co-)precipitation. These precipitates conversely inhibited the subsequent mineral dissolution by covering the tailing surface. FDCs also enhanced the tailings' porosities by 2.94%-9.94%. The mineral dissolution, expansion and shrinkage, and changes in tension destroyed the tailing microstructure during FDCs. This study demonstrated the low metal pollution risk of VTMTs under FDCs, either in acid rain or bio-secreted organic acids. However, the increase in tailing porosity should be seriously considered as it would affect the tailing pond safety.
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Affiliation(s)
- Dan Zhou
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China; State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, China
| | - Chao Li
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China
| | - Mingzheng Huang
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China
| | - Xiaoyan Chen
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China
| | - Yonglian Xia
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China
| | - Yi Huang
- State Environmental Protection Key Laboratory of Synergetic Control and Joint Remediation for Soil & Water Pollution, College of Ecology and Environment, Chengdu University of Technology, Chengdu, 610059, China; State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu, 610059, China.
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2
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Sanjana S, Jazeel K, Janeeshma E, Nair SG, Shackira AM. Synergistic interactions of assorted ameliorating agents to enhance the potential of heavy metal phytoremediation. STRESS BIOLOGY 2024; 4:13. [PMID: 38363436 PMCID: PMC10873264 DOI: 10.1007/s44154-024-00153-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 01/29/2024] [Indexed: 02/17/2024]
Abstract
Pollution by toxic heavy metals creates a significant impact on the biotic community of the ecosystem. Nowadays, a solution to this problem is an eco-friendly approach like phytoremediation, in which plants are used to ameliorate heavy metals. In addition, various amendments are used to enhance the potential of heavy metal phytoremediation. Symbiotic microorganisms such as phosphate-solubilizing bacteria (PSB), endophytes, mycorrhiza and plant growth-promoting rhizobacteria (PGPR) play a significant role in the improvement of heavy metal phytoremediation potential along with promoting the growth of plants that are grown in contaminated environments. Various chemical chelators (Indole 3-acetic acid, ethylene diamine tetra acetic acid, ethylene glycol tetra acetic acid, ethylenediamine-N, N-disuccinic acid and nitrilotri-acetic acid) and their combined action with other agents also contribute to heavy metal phytoremediation enhancement. With modern techniques, transgenic plants and microorganisms are developed to open up an alternative strategy for phytoremediation. Genomics, proteomics, transcriptomics and metabolomics are widely used novel approaches to develop competent phytoremediators. This review accounts for the synergistic interactions of the ameliorating agent's role in enhancing heavy metal phytoremediation, intending to highlight the importance of these various approaches in reducing heavy metal pollution.
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Affiliation(s)
- S Sanjana
- Department of Botany, Sir Syed College, Kannur University, Kerala, 670142, India
| | - K Jazeel
- Department of Botany, Sir Syed College, Kannur University, Kerala, 670142, India
| | - E Janeeshma
- Department of Botany, MES KEVEEYAM College, Valanchery, Malappuram, Kerala, India
| | - Sarath G Nair
- Department of Botany, Mar Athanasius College, Mahatma Gandhi University, Kottayam, Kerala, India
| | - A M Shackira
- Department of Botany, Sir Syed College, Kannur University, Kerala, 670142, India.
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Ni S, Rahman S, Harada Y, Yoshioka S, Imaizumi M, Wong KH, Mashio AS, Ohta A, Hasegawa H. Remediation of cadmium-contaminated soil: GLDA-assisted extraction and sequential FeCl 3-CaO-based post-stabilization. CHEMOSPHERE 2024; 346:140554. [PMID: 38303381 DOI: 10.1016/j.chemosphere.2023.140554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/23/2023] [Accepted: 10/25/2023] [Indexed: 02/03/2024]
Abstract
Cadmium (Cd) contamination of farmland soils is a growing concern because of its highly toxic impact on ecosystems and human health. Chelator-assisted washing and chemical immobilization are effective remediation strategies for Cd-contaminated soils. Ethylenediaminetetraacetic acid (EDTA) has traditionally been used for soil washing, but its persistence in the environment and subsequent toxicity have raised significant ecological concerns. Consequently, biodegradable chelators have gained increasing attention as eco-friendly alternatives to the persistent chelator, EDTA. Therefore, this study evaluated the performance and efficacy of three biodegradable chelators: L-glutamate-N,N'-diacetic acid (GLDA), methylglycine-diacetic acid (MGDA), and 3-hydroxy-2,2'-iminodisuccinic acid (HIDS) in comparison to EDTA for remediating a real Cd-contaminated agricultural soil. The influence of treatment parameters, including chelator variants, washing time, chelator concentration, solution pH, and liquid-to-soil ratio (L/S) on Cd extraction was studied and optimized to attain the maximum removal rate. Following chelator-assisted washing, the efficacy of a stabilization preference combining FeCl3 and CaO in reducing the leaching potential of residual Cd in chelator-washed soil residues was also investigated. GLDA demonstrated comparable Cd extraction efficiency to EDTA, and the Cd extraction efficiency was found to be positively correlated with the soil washing parameters. However, under the optimized conditions (chelator concentration: 10 mmol L-1; washing time: 3 h; solution pH: 3; L/S ratio: 10:1), GLDA exhibited a higher Cd extraction rate than EDTA or the other chelators. Furthermore, a post-treatment process incorporating FeCl3 and CaO substantially diminished the water-leachable Cd content in the resultant soil residues. The proposed remediation strategy, which combines chemically assisted washing and stabilization, could be a practical option for extracting bulk Cd from soil and reducing the leaching potential of residual Cd.
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Affiliation(s)
- Shengbin Ni
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan.
| | - Shafiqur Rahman
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan.
| | - Yasuhiro Harada
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan
| | - Shoji Yoshioka
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan
| | - Minami Imaizumi
- Graduate School of Natural Science and Technology, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan
| | - Kuo H Wong
- Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan
| | - Asami S Mashio
- Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan
| | - Akio Ohta
- Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan
| | - Hiroshi Hasegawa
- Institute of Science and Engineering, Kanazawa University, Kakuma, Kanazawa, 920-1192, Japan.
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Xu Z, Pan J, Ullah N, Duan Y, Hao R, Li J, Huang Q, Xu L. 5-Aminolevulinic acid mitigates the chromium-induced changes in Helianthus annuus L. as revealed by plant defense system enhancement. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2023; 198:107701. [PMID: 37105019 DOI: 10.1016/j.plaphy.2023.107701] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2023] [Revised: 03/14/2023] [Accepted: 04/10/2023] [Indexed: 05/07/2023]
Abstract
Chromium (Cr) in the soil is one of the major pollutants for agricultural production. This study examined the efficiency of sunflower plants to remediate Cr-contaminated soils using a plant growth regulator, 5-aminolevolinic acid (ALA). At six leaf stage, sunflower plants were exposed to soil-applied Cr (0.15 g kg-1), manganese (Mn, 0.3 g kg-1) and trisodium (S,S)-ethylenediamine-N,N'-disuccinic acid (EDDS, 2.5 mmol kg-1), ALA (10 mg L-1) was sprayed. After ALA treatment, the plants were harvested for further biochemical analyses. Results showed that EDDS and Mn improved the Cr accumulation but restrained plant growth. Conversely, ALA improved the growth of Cr-stressed plants by promoting chlorophyll concentration in the top fully expanded leaves. The bioaccumulation quantity and removal efficiency of sunflowers treated by Cr + EDDS + ALA was improved by 47.92% and 47.94%, respectively, as compared to the Cr treatment. This was further supported by qRT-PCR analysis, where the expression of heavy metal transport genes such as ZIP6 and NRAMP6 and subsequently Cr accumulation in sunflower tissues increased by EDDS, Mn, and ALA application. However, compared with other treatments, ALA ameliorated cellular injury from Cr-stress by uptake or movement of Cr prevention, modulation of antioxidant enzymes, and elimination of reactive oxygen species. Our study suggested that ALA as an ideal option for the phytoremediation of Cr-contaminated soils.
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Affiliation(s)
- Zishu Xu
- Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province , College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jianmin Pan
- Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province , College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Najeeb Ullah
- Agricultural Research Station, Office of VP for Research & Graduate Studies, Qatar University, Doha 2713, Qatar
| | - Yi Duan
- Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province , College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Ruiyong Hao
- Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province , College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Juanjuan Li
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou 310058, China
| | - Qian Huang
- Institute of Crop Science, Ministry of Agriculture and Rural Affairs Laboratory of Spectroscopy Sensing, Zhejiang University, Hangzhou 310058, China
| | - Ling Xu
- Key Laboratory of Plant Secondary Metabolism and Regulation of Zhejiang Province , College of Life Sciences and Medicine, Zhejiang Sci-Tech University, Hangzhou 310018, China.
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Chengatt AP, Sarath NG, Sebastian DP, Mohanan NS, Sindhu ES, George S, Puthur JT. Chelate assisted phytoextraction for effective rehabilitation of heavy metal(loid)s contaminated lands. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2022; 25:981-996. [PMID: 36148488 DOI: 10.1080/15226514.2022.2124233] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The contamination of lands and water by heavy toxic metal(loid)s is an environmental issue that needs serious attention as it poses a major threat to public health. The persistence of heavy metals/metalloids in the environment as well as their potentially dangerous effects on organisms underpins the need to restore the areas contaminated by heavy toxic metal(loid)s. Soil restoration can be achieved through a variety of different methods. Being more cost-effective and environmentally sustainable, phytoremediation has recently replaced traditional processes like soil washing and burning. Many plants have been intensively explored to eliminate various heavy metals from polluted soils through phytoextraction, which is a commonly used phytoremediation approach. The ability of chelants to enhance phytoextraction potential has also received wide attention owing to their ability to elevate the efficiency of plants in removing heavy metal(loid)s. Chelants have been found to improve plant growth and the activity of the defense system. Several chelants, either non-biodegradable or biodegradable, have been reported to augment the phytoextraction efficiencies of various plants. The problem of the leaching of heavy metal(loid)s and secondary pollution caused by non-biodegradable chelants can be overcome by the use of biodegradable chelants to an extent. This review is a brief report focusing on recent articles on chelate-assisted phytoextraction of heavy metal (loids) As, Cd, Cu, Cr, Hg, Ni, Pb, U, and Zn.
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Affiliation(s)
| | - Nair G Sarath
- Plant Physiology and Biochemistry Division, Department of Botany, University of Calicut, Kozhikode, India
| | | | | | - E S Sindhu
- Department of Botany, St. Joseph's College (Autonomous), Kozhikode, India
| | - Satheesh George
- Department of Botany, St. Joseph's College (Autonomous), Kozhikode, India
| | - Jos T Puthur
- Plant Physiology and Biochemistry Division, Department of Botany, University of Calicut, Kozhikode, India
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Chelating Agents in Assisting Phytoremediation of Uranium-Contaminated Soils: A Review. SUSTAINABILITY 2022. [DOI: 10.3390/su14106379] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Massive stockpiles of uranium (U) mine tailings have resulted in soil contamination with U. Plants for soil remediation have low extraction efficiency of U. Chelating agents can mobilize U in soils and, hence, enhance phytoextraction of U from the soil. However, the rapid mobilization rate of soil U by chelating agents in a short period than plant uptake rate could increase the risk of groundwater contamination with soluble U leaching down the soil profile. This review summarizes recent progresses in synthesis and application of chelating agents for assisting phytoremediation of U-contaminated soils. In detail, the interactions between chelating agents and U ions are initially elucidated. Subsequently, the mechanisms of phytoextraction and effectiveness of different chelating agents for phytoremediation of U-contaminated soils are given. Moreover, the potential risks associated with chelating agents are discussed. Finally, the synthesis and application of slow-release chelating agents for slowing down metal mobilization in soils are presented. The application of slow-release chelating agents for enhancing phytoextraction of soil U is still scarce. Hence, we propose the preparation of slow-release biodegradable chelating agents, which can control the release speed of chelating agent into the soil in order to match the mobilization rate of soil U with plant uptake rate, while diminishing the risk of residual chelating agent leaching to groundwater.
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7
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Wang X, Fernandes de Souza M, Li H, Qiu J, Ok YS, Meers E. Biodegradation and effects of EDDS and NTA on Zn in soil solutions during phytoextraction by alfalfa in soils with three Zn levels. CHEMOSPHERE 2022; 292:133519. [PMID: 34995634 DOI: 10.1016/j.chemosphere.2022.133519] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 12/07/2021] [Accepted: 12/31/2021] [Indexed: 06/14/2023]
Abstract
In chelator-enhanced Zn phytoremediation studies, it is crucial to understand how the degradable chelators and the competition from other ions influence the concentration of Zn in soil solutions. This study investigated the biodegradability of two chelators (EDDS: Ethylenediamine-N,N'-disuccinic acid, and NTA: Nitrilotriacetic acid) and their effects on the Zn concentration in the soil solution during the growth of alfalfa (Medicago Sativa L.). The chelators were added at four doses (0, 0.5, 2 and 5 mmol kg-1) in soils with varying Zn levels (189, 265 and 1496 mg kg-1). The results showed that the lag phase before EDDS and NTA biodegradation varied from 0 to 7 days in the three soils. EDDS and NTA were completely decomposed within the assessed 57 days regardless of the applied dosage, with a half-life of 1.3-3.0 days in highly Zn-contaminated soil and 4.2-10.8 days in the two other soils. In soil solutions, the change in solubilized Zn was in line with EDDS and NTA degradation kinetics. Cu, Al, Fe and Mn were the main metal ions that competed against Zn for chelation. Besides, Ni competed with Zn in the whole process. Ca did not compete effectively in the three soils, while Mg was a competitor only at the initial stage. Our results show the importance of considering both the biodegradation rate and the competition between the target cation and other elements present in the soil when using chelators to enhance phytoremediation. A 30-day explorative incubation experiment is recommended to evaluate the appropriate application time of chelators and the target Zn exposure time for plants during phytoremediation.
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Affiliation(s)
- Xiaolin Wang
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium.
| | - Marcella Fernandes de Souza
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium
| | - Haichao Li
- Department of Environment, Ghent University, Coupure links 653, 9000, Ghent, Belgium
| | - Jing Qiu
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium
| | - Yong Sik Ok
- Korea Biochar Research Center, APRU Sustainable Waste Management & Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Erik Meers
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000, Ghent, Belgium
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Tochaikul G, Phattanasub A, Khemkham P, Saengthamthawee K, Danthanavat N, Moonkum N. Radioactive waste treatment technology: a review. KERNTECHNIK 2022. [DOI: 10.1515/kern-2021-1029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Radioactive waste is generated from activities that utilize nuclear materials such as nuclear medicine or power plants. Depending on their half-life, they emit radiation continuously, ranging from seconds to millions of years. Exposure to ionizing radiation can cause serious harm to humans and the environment. Therefore, special attention is paid to the management of radioactive waste in order to deal with its large quantity and dangerous levels. Current treatment technologies are still being developed to improve efficiency in reducing the hazard level and waste volume, to minimize the impact on living organisms. Thus, the aim of this study was to provide an overview of the global radioactive waste treatment technologies that have been released in 2019–2021.
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Affiliation(s)
- Gunjanaporn Tochaikul
- Faculty of Radiological Technology, Rangsit University , 52/347 Lak Hok, Mueang Pathum Thani District , Pathum Thani 12000 , Thailand
| | - Archara Phattanasub
- Head of Radioactive Waste Technology and Development Section, Thailand Institute of Nuclear Technology (Public Organization) , Bangkok , Thailand
| | - Piyatida Khemkham
- Faculty of Radiological Technology, Rangsit University , 52/347 Lak Hok, Mueang Pathum Thani District , Pathum Thani 12000 , Thailand
| | - Kanjanaporn Saengthamthawee
- Faculty of Radiological Technology, Rangsit University , 52/347 Lak Hok, Mueang Pathum Thani District , Pathum Thani 12000 , Thailand
| | - Nuttapong Danthanavat
- Faculty of Radiological Technology, Rangsit University , 52/347 Lak Hok, Mueang Pathum Thani District , Pathum Thani 12000 , Thailand
| | - Nutthapong Moonkum
- Faculty of Radiological Technology, Rangsit University , 52/347 Lak Hok, Mueang Pathum Thani District , Pathum Thani 12000 , Thailand
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Wang X, Fernandes de Souza M, Mench MJ, Li H, Ok YS, Tack FMG, Meers E. Cu phytoextraction and biomass utilization as essential trace element feed supplements for livestock. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 294:118627. [PMID: 34871647 DOI: 10.1016/j.envpol.2021.118627] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 11/21/2021] [Accepted: 12/01/2021] [Indexed: 06/13/2023]
Abstract
Copper (Cu), as an essential element, is added to animal feed to stimulate growth and prevent disease. The forage crop alfalfa (Medicago sativa L.) produced during Cu phytoextraction may be considered a biofortified crop to substitute the Cu feed additives for livestock production, beneficially alleviating Cu contamination in soils and reducing its input into agriculture systems. To assess this, alfalfa was grown in three similar soils with different Cu levels, i.e., 11, 439 and 779 mg kg-1 for uncontaminated soil (A), moderately Cu-contaminated soil (B) and highly Cu-contaminated soil (C), respectively. EDDS (Ethylenediamine-N,N'-disuccinic acid) was applied to the soils seven days before the first cutting at four rates (0, 0.5, 2 and 5 mmol kg-1) to enhance bioavailable Cu uptake. Alfalfa grew well in soils A and B but not in the highly Cu-contaminated soil. After applying EDDS, a significant biomass reduction of the first cutting shoot was only observed with 5 mmol kg-1 EDDS in the highly Cu-contaminated soil, with a 45% (P < 0.05) decrease when compared to the control. Alfalfa grown in the three soils gradually wilted after the first cutting with 5 mmol kg-1 EDDS, and Cu concentrations in the first cutting shoot were augmented strongly, by 250% (P < 0.05), 3500% (P < 0.05) and 6700% (P < 0.05) compared to the controls, respectively. Cu concentrations in alfalfa shoots were found to be higher in this study than in some fodder plants and further augmented in soils with higher Cu levels and with EDDS application. These findings suggest that alfalfa grown on clean soils or soils with up to 450 mg Cu kg-1 (with appropriate EDDS dosages) has the potential to be considered as a partial Cu supplementation for livestock. This research laid the foundation for the integration between Cu-phytoextraction and Cu-biofortification for livestock.
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Affiliation(s)
- Xiaolin Wang
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium.
| | - Marcella Fernandes de Souza
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | | | - Haichao Li
- Department of Environment, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Yong Sik Ok
- Korea Biochar Research Center, APRU Sustainable Waste Management & Division of Environmental Science and Ecological Engineering, Korea University, Seoul, 02841, Republic of Korea
| | - Filip M G Tack
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
| | - Erik Meers
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure Links 653, 9000, Ghent, Belgium
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10
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Farinelli G, Coha M, Minella M, Fabbri D, Pazzi M, Vione D, Tiraferri A. Evaluation of Fenton and modified Fenton oxidation coupled with membrane distillation for produced water treatment: Benefits, challenges, and effluent toxicity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 796:148953. [PMID: 34328879 DOI: 10.1016/j.scitotenv.2021.148953] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Revised: 07/05/2021] [Accepted: 07/06/2021] [Indexed: 06/13/2023]
Abstract
Membrane distillation is a promising technology to desalinate hypersaline produced waters. However, the organic content can foul and wet the membrane, while some fractions may pass into the distillate and impair its quality. In this study, the applicability of the traditional Fenton process was investigated and preliminarily optimized as a pre-treatment of a synthetic hypersaline produced water for the following step of membrane distillation. The Fenton process was also compared to a modified Fenton system, whereby safe iron ligands, i.e., ethylenediamine-N,N'-disuccinate and citrate, were used to overcome practical limitations of the traditional reaction. The oxidation pre-treatments achieved up to 55% removal of the dissolved organic carbon and almost complete degradation of the low molecular weight toxic organic contaminants. The pre-treatment steps did not improve the productivity of the membrane distillation process, but they allowed for obtaining a final effluent with significantly higher quality in terms of organic content and reduced Vibrio fischeri inhibition, with half maximal effective concentration (EC50) values up to 25 times those measured for the raw produced water. The addition of iron ligands during the oxidation step simplified the process, but resulted in an effluent of slightly lower quality in terms of toxicity compared to the use of traditional Fenton.
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Affiliation(s)
- Giulio Farinelli
- Department of Environment, Land and Infrastructure Engineering (DIATI), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy
| | - Marco Coha
- Department of Environment, Land and Infrastructure Engineering (DIATI), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy
| | - Marco Minella
- Department of Chemistry, Università di Torino, Via Pietro Giuria 5, 10125 Turin, Italy
| | - Debora Fabbri
- Department of Chemistry, Università di Torino, Via Pietro Giuria 5, 10125 Turin, Italy
| | - Marco Pazzi
- Department of Chemistry, Università di Torino, Via Pietro Giuria 5, 10125 Turin, Italy
| | - Davide Vione
- Department of Chemistry, Università di Torino, Via Pietro Giuria 5, 10125 Turin, Italy
| | - Alberto Tiraferri
- Department of Environment, Land and Infrastructure Engineering (DIATI), Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129 Turin, Italy.
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11
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Akhtar N, Ilyas N, Mashwani ZUR, Hayat R, Yasmin H, Noureldeen A, Ahmad P. Synergistic effects of plant growth promoting rhizobacteria and silicon dioxide nano-particles for amelioration of drought stress in wheat. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 166:160-176. [PMID: 34116336 DOI: 10.1016/j.plaphy.2021.05.039] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 05/25/2021] [Indexed: 06/12/2023]
Abstract
Drought tolerant plant growth-promoting rhizobacteria (PGPR) can confer drought tolerance in plants, when inoculated, and this effect can be more pronounced by their combined application with silicon oxide nanoparticles (SiO2 NPs). In this research, drought-tolerant and plant growth-promoting rhizobacterial strains were isolated from the rhizospheric soil of wheat plants growing in the arid region of Pakistan. Out of 30 isolated strains, three rhizobacterial strains were selected based on their drought tolerance, higher phytohormones (indole acetic acid (IAA), abscisic acid (ABA), and cytokinin (CK), and osmolyte (proline and sugar) production ability. These strains were identified as Bacillus sp. Azospirillum lipoferum and Azospirillum brasilense by 16S rRNA sequencing and accession numbers (MT482404, MT742664, and MT 742666, respectively) were obtained. Inoculation of these strains, alone and in combination, improved the germination attributes of wheat seeds under drought stress conditions. However, the combination of all three bacterial strains gave the best results. SiO2 NPs were prepared from silicon dioxide and characterized by scanning electron microscopy (SEM), Energy dispersive X-rays pattern (EDX), and UV-visible spectrum. The effect of SiO2 NPs was also tested on wheat seeds under drought stress and it was observed that SiO2 NPs (150 mg/L) create pronounced drought ameliorative potential in wheat seedlings. In the pot experiment, the combined application of SiO2 NPs and PGPR exhibited a synergistic role and improved the growth and yield of wheat. The interaction between SiO2 NPs and bacterial combination improved biomass (fresh and dry weight), and chlorophyll-a, b content by 138.78%, 65.70%, 128.57%, and 283.33% respectively as compared to untreated but drought exposed plants. They also improved relative water content (71.66%), gas exchange attributes, increased nutrients uptake, and osmolytes production of wheat. Up-regulation of antioxidant enzymes; superoxide dismutase (60.49%), peroxidase (55.99%), and catalase (81.69%) was also observed. This research work suggested that the application of SiO2 NPs and PGPR strains induced drought tolerance in wheat by modulating different physiological and metabolic processes in plants which ultimately improved the growth and yield of wheat under drought stress.
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Affiliation(s)
- Nosheen Akhtar
- Department of Botany, PMAS-Arid University Rawalpindi, 46300, Rawalpindi, Pakistan
| | - Noshin Ilyas
- Department of Botany, PMAS-Arid University Rawalpindi, 46300, Rawalpindi, Pakistan.
| | | | - Rifat Hayat
- Institute of Soil Science, PMAS-Arid Agriculture University Rawalpindi, 46300, Rawalpindi, Pakistan
| | - Humaira Yasmin
- Department of Biosciences, COMSATS University, 45550, Islamabad, Pakistan
| | - Ahmed Noureldeen
- Department of Biology, College of Sciences, Taif University, P.O. Box 11099, Taif, 21944, Saudi Arabia
| | - Parvaiz Ahmad
- Department of Botany, S.P. College, Srinagar, Jammu, and Kashmir, India
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12
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Han R, Dai H, Skuza L, Wei S. Comparative study on different organic acids for promoting Solanum nigrum L. hyperaccumulation of Cd and Pb from the contaminated soil. CHEMOSPHERE 2021; 278:130446. [PMID: 33838411 DOI: 10.1016/j.chemosphere.2021.130446] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 03/18/2021] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Organic acids-assisted phytoremediation is a promising strategy to remove metal pollutants from the soil. However, few reports have focused on the mechanisms of organic acids promoting the uptake of heavy metals by hyperaccumulators. In this study, 5 types of organic acids, namely polybasic carboxylic acids, acidic amino acids, acidic plant growth regulators, phosphoric and gluconic acids, were comprehensively investigated the effects on the solubility of Cd and Pb in the soil along with their uptake by Cd hyperaccumulator Solanum nigrum L. The results indicated that the addition of Hydroxyethylidene-1,1-diphosphonic acid (HEDP) and d-Gluconic acid (D-GA) effectively extracted the most of acid-extractable and some of reducible and oxidizable fractions of Cd and Pb in the soil, with the extraction rates of 64.8% and 34.4% for total Cd and 53.6% and 30.0% for total Pb, respectively. HEDP and D-GA significantly increased the accumulations of Cd (57.1% and 35.0%) and Pb (43.4% and 31.9%) by S. nigrum without the inhibition of its biomass, making the great removal efficiencies of Cd (1.35% and 1.16%) and Pb (0.039% and 0.036%) from the soil. The enhanced phytoremediation efficiency of S. nigrum was due to the increase of the extractable Cd and Pb in the rhizosphere but little changes of soil pH and enzyme activities (catalase and urease). Among all of organic acids, HEDP may be an alternative to EDTA because of its characteristics of environmental friendliness and high efficiency.
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Affiliation(s)
- Ran Han
- Key Lab of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, PR China
| | - Huiping Dai
- College of Biological Science & Engineering, Shaanxi University of Technology, Hanzhong, 723001, PR China
| | - Lidia Skuza
- Department of Molecular Biology and Cytology, Institute for Research on Biodiversity, University of Szczecin, Szczecin, 71-415, Poland
| | - Shuhe Wei
- Key Lab of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, 110016, PR China.
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13
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Wang Y, Xu Y, Qin X, Zhao L, Huang Q, Liang X. Effects of S,S-ethylenediamine disuccinic acid on the phytoextraction efficiency of Solanum nigrum L. and soil quality in Cd-contaminated alkaline wheat soil. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:42959-42974. [PMID: 33830419 DOI: 10.1007/s11356-021-13764-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2020] [Accepted: 03/29/2021] [Indexed: 06/12/2023]
Abstract
Degradable chelating agent-assisted phytoextraction is a promising method for the remediation of Cd-contaminated agricultural soil. However, there are limited studies that have examined the effect of chelating agents on soil solutions and soil quality in alkaline soil. In this study, the effects of S,S-ethylenediamine disuccinic acid (EDDS) on the growth and phytoextraction of Solanum nigrum L. (S. nigrum) were studied using pot experiments. The influence of EDDS on the soil solutions, heavy metal contents, and soil enzyme activities was evaluated. EDDS application increased the height of S. nigrum by 7.25-29.25 cm and increased the biomass of stem and leaf by 4.26-14.95 and 1.14-10.78 g/pot, respectively. The Cd concentrations in the leaves and berries of S. nigrum were 1.21-2.17 and 1.7-9.47 times higher than that of the control, respectively, and the Cd extraction amount in the shoots of S. nigrum increased by 22.78-256.16 μg/pot after EDDS application. The chelation of EDDS on heavy metals reached a peak after 7 days of application, decreased gradually with the degradation of EDDS, and disappeared after 30 days of application. Soil pH, available metals, metal speciation, and soil urease were significantly related to the application time of EDDS. Importantly, EDDS application 45 days before S. nigrum harvest treatments decreased the available metal concentrations and improved soil pH and urease activity. However, when EDDS was applied 15 days before S. nigrum harvest, the available Cd and Pb concentrations significantly increased and caused additional Pb pollution. Considering the chelation and degradation effects, the environmental implication, and the cost of EDDS, the results of this study showed that one application of EDDS was better than two applications, a 45-day application before harvest was preferred to a 15-day application, and application of 1-3 mM EDDS 30-45 days before S. nigrum harvest was the most promising application method for the remediation of Cd-contaminated alkaline soil.
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Affiliation(s)
- Yale Wang
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
- Key Laboratory of Original Environmental Pollution Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
| | - Yingming Xu
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
- Key Laboratory of Original Environmental Pollution Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Xu Qin
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
- Key Laboratory of Original Environmental Pollution Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
| | - Lijie Zhao
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
- Key Laboratory of Original Environmental Pollution Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
| | - Qingqing Huang
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
- Key Laboratory of Original Environmental Pollution Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
| | - Xuefeng Liang
- Innovation Team of Remediation for Heavy Metal Contaminated Farmlands, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
- Key Laboratory of Original Environmental Pollution Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China
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14
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Nugroho AP, Butar ESB, Priantoro EA, Sriwuryandari L, Pratiwi ZB, Sembiring T. Phytoremediation of electroplating wastewater by vetiver grass (Chrysopogon zizanoides L.). Sci Rep 2021; 11:14482. [PMID: 34262111 PMCID: PMC8280137 DOI: 10.1038/s41598-021-93923-0] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2020] [Accepted: 06/14/2021] [Indexed: 02/06/2023] Open
Abstract
The electroplating industry generates wastewater containing a variety of heavy metals which potentially contaminate water ecosystems. The available and well-known electroplating wastewater treatments are considered as an expensive and less effective method, therefore phytoremediation was used as an alternative friendly solution. This study aims to evaluate the uptake and elimination rate of heavy metals by vetiver (Chrysopogon zizanoides L.) on metal-polluted water. Vetiver was planted in artificial electroplating wastewater containing different levels (low, medium, high) of chromium (Cr) and nickel (Ni). Water, roots, and shoots were collected periodically to determine Cr and Ni contents using Atomic Absorption Spectrometry (AAS). Metal accumulation and elimination rate, Bioconcentration Factor (BCF), Biological Absorption Coefficient (BAC), and Translocation Factor (TF) were calculated to evaluate plant's effectiveness in metal remediation processes. The results showed that vetiver (C. zizanoides L.) was able to remove 61.10% Cr and 95.65% Ni on metal-contaminated water. The highest uptake rates for Cr and Ni are 127.21 mg/kg/day and 15.60 mg/kg/day respectively, while the elimination rates for Cr and Ni tend to slow 1.09 mg/kg/day and 12.24 mg/kg/day respectively. Vetiver BCF, BAC, and TF values on Cr and Ni contaminated water were greater than 1, which indicates that vetiver work through phytoextraction and phytostabilization to treat metals. The findings showed that vetiver has promise as a phytoremediation agent thus providing implication for electroplating wastewater treatment.
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Affiliation(s)
| | - Erni Saurmalinda Butar Butar
- Waste Treatment and Environmental Management Working Group, Research Unit for Clean Technology – Indonesian Institute of Sciences, Bandung, Indonesia
| | - Ekaputra Agung Priantoro
- Waste Treatment and Environmental Management Working Group, Research Unit for Clean Technology – Indonesian Institute of Sciences, Bandung, Indonesia
| | - Lies Sriwuryandari
- Waste Treatment and Environmental Management Working Group, Research Unit for Clean Technology – Indonesian Institute of Sciences, Bandung, Indonesia
| | | | - Tarzan Sembiring
- Waste Treatment and Environmental Management Working Group, Research Unit for Clean Technology – Indonesian Institute of Sciences, Bandung, Indonesia
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15
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Chen L, Liu J, Zhang W, Zhou J, Luo D, Li Z. Uranium (U) source, speciation, uptake, toxicity and bioremediation strategies in soil-plant system: A review. JOURNAL OF HAZARDOUS MATERIALS 2021; 413:125319. [PMID: 33582470 DOI: 10.1016/j.jhazmat.2021.125319] [Citation(s) in RCA: 79] [Impact Index Per Article: 26.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/23/2021] [Accepted: 02/02/2021] [Indexed: 06/12/2023]
Abstract
Uranium(U), a highly toxic radionuclide, is becoming a great threat to soil health development, as returning nuclear waste containing U into the soil systems is increased. Numerous studies have focused on: i) tracing the source in U contaminated soils; ii) exploring U geochemistry; and iii) assessing U phyto-uptake and its toxicity to plants. Yet, there are few literature reviews that systematically summarized the U in soil-plant system in past decade. Thus, we present its source, geochemical behavior, uptake, toxicity, detoxification, and bioremediation strategies based on available data, especially published from 2018 to 2021. In this review, we examine processes that can lead to the soil U contamination, indicating that mining activities are currently the main sources. We discuss the relationship between U bioavailability in the soil-plant system and soil conditions including redox potential, soil pH, organic matter, and microorganisms. We then review the soil-plant transfer of U, finding that U mainly accumulates in roots with a quite limited translocation. However, plants such as willow, water lily, and sesban are reported to translocate high U levels from roots to aerial parts. Indeed, U does not possess any identified biological role, but provokes numerous deleterious effects such as reducing seed germination, inhibiting plant growth, depressing photosynthesis, interfering with nutrient uptake, as well as oxidative damage and genotoxicity. Yet, plants tolerate U toxicity via various defense strategies including antioxidant enzymes, compartmentalization, and phytochelatin. Moreover, we review two biological remediation strategies for U-contaminated soil: (i) phytoremediation and (ii) microbial remediation. They are quite low-cost and eco-friendly compared with traditional physical or chemical remediation technologies. Finally, we conclude some promising research challenges regarding U biogeochemical behavior in soil-plant systems. This review, thus, further indicates that the combined application of U low accumulators and microbial inoculants may be an effective strategy for the bioremediation of U-contaminated soils.
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Affiliation(s)
- Li Chen
- State Key Laboratory of Grassland Agro-ecosystems; Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs; Engineering Research Center of Grassland Industry, Ministry of Education, Gansu Tech Innovation Center of Western China Grassland Industry; College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, Gansu, PR China
| | - Jinrong Liu
- State Key Laboratory of Grassland Agro-ecosystems; Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs; Engineering Research Center of Grassland Industry, Ministry of Education, Gansu Tech Innovation Center of Western China Grassland Industry; College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, Gansu, PR China.
| | - Weixiong Zhang
- Third Institute Geological and Mineral Exploration of Gansu Provincial Bureau of Geology and Mineral Resources, Lanzhou 730030, Gansu, PR China
| | - Jiqiang Zhou
- Gansu Nonferrous Engineering Exploration & Design Research Institute, Lanzhou 730030, Gansu, PR China
| | - Danqi Luo
- State Key Laboratory of Grassland Agro-ecosystems; Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs; Engineering Research Center of Grassland Industry, Ministry of Education, Gansu Tech Innovation Center of Western China Grassland Industry; College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, Gansu, PR China
| | - Zimin Li
- Université catholique de Louvain (UCLouvain), Earth and Life Institute, Soil Science, Louvain-La-Neuve 1348, Belgium.
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16
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Wang X, Fernandes de Souza M, Li H, Tack FMG, Ok YS, Meers E. Zn phytoextraction and recycling of alfalfa biomass as potential Zn-biofortified feed crop. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 760:143424. [PMID: 33223175 DOI: 10.1016/j.scitotenv.2020.143424] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Revised: 10/14/2020] [Accepted: 10/20/2020] [Indexed: 06/11/2023]
Abstract
Zn is an essential micronutrient for living organisms and, in that capacity, it is added to animal feed in intensive livestock production to promote growth and eliminate diseases. Alfalfa (Medicago sativa L.) may have the potential to compensate and substitute the need for chemical Zn additives in feeds as a Zn-biofortified feed crop when grown on Zn-enriched soils. Thus, this possibility was investigated with a greenhouse experiment using three soils with Zn concentrations (mg kg-1) of 189 (soil A), 265 (soil B) and 1496 (soil C). Ethylenediamine-N,N'-disuccinate acid (EDDS) and Nitrilotriacetic acid (NTA) at different rates (0 as control, 0.5, 2 and 5 mmol kg-1) were applied as soil additives to enhance the phytoextraction efficiency of alfalfa. The results showed that Zn was highly transferable in alfalfa tissues in the three soils even without additives. EDDS was more effective than NTA in enhancing Zn phytoextraction by alfalfa. The maximum Zn accumulation in the third cutting shoots was obtained with the EDDS concentration of 5 mmol kg-1 in soil A and of 2 mmol kg-1 in soil B, with a 462% and 162% increase compared with controls, respectively. However, the higher EDDS concentration resulted in a significant reduction in biomass production. In soil C, all EDDS concentrations resulted in similar Zn accumulations in the third shoot. To improve the phytoextraction efficacy of Zn while minimizing its phytotoxicity on alfalfa, the rate of 2 mmol kg-1 EDDS proved to be optimal for soil B, and 0.5 mmol kg-1 EDDS for soils A and C. Findings suggest that phytoextraction of Zn-enriched soil can be combined with Zn biofortification, thus allowing to recycle Zn into biomass that can, to an extent, substitute Zn feed additives. This study provided a primary data set for the combination of Zn-biofortification and Zn-phytoextraction.
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Affiliation(s)
- Xiaolin Wang
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium.
| | - Marcella Fernandes de Souza
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Haichao Li
- Department of Environment, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Filip M G Tack
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
| | - Yong Sik Ok
- Korea Biochar Research Center, APRU Sustainable Waste Management & Division of Environmental Science and Ecological Engineering, Korea University, Seoul 02841, Republic of Korea
| | - Erik Meers
- Department of Green Chemistry and Technology, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, 9000 Ghent, Belgium
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