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Tang L, Gao W, Lu Y, Tabelin CB, Liu J, Li H, Yang W, Tang C, Feng X, Jiang J, Xue S. The formation of multi-metal(loid)s contaminated groundwater at smelting site: Critical role of natural colloids. JOURNAL OF HAZARDOUS MATERIALS 2024; 471:134408. [PMID: 38678716 DOI: 10.1016/j.jhazmat.2024.134408] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Revised: 03/22/2024] [Accepted: 04/23/2024] [Indexed: 05/01/2024]
Abstract
The occurrence and migration of colloids at smelting sites are crucial for the formation of multi-metal(loid)s pollution in groundwater. In this study, the behavior of natural colloids (1 nm-0.45 µm) at an abandoned smelting site was investigated by analyzing groundwater samples filtered through progressively decreasing pore sizes. Smelting activities in this site had negatively impacted the groundwater quality, leading to elevated concentrations of zinc (Zn), lead (Pb), arsenic (As), and cadmium (Cd). The results showed that heavy metal(loid)-bearing colloids were ubiquitous in the groundwater with the larger colloidal fractions (∼75 -450 nm) containing higher abundances of pollutants. It was also observed that the predominant colloids consisted of Zn-Al layered double hydroxide (LDH), sphalerite, kaolinite, and hematite. By employing multiple analytical techniques, including leaching experiments, soil colloid characterization, and Pb stable isotope measurements, the origin of groundwater colloids was successfully traced to the topsoil colloids. Most notably, our findings highlighted the increased risk of heavy metal(loid)s migration from polluted soils into adjacent sites through the groundwater because of colloid-mediated transport of contaminants. This field-scale investigation provides valuable insights into the geochemical processes governing heavy metal(loid) behavior as well as offering pollution remediation strategies specifically tailored for contaminated groundwater.
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Affiliation(s)
- Lu Tang
- School of Metallurgy and Environment, Central South University, Hunan 410083, China
| | - Wenyan Gao
- School of Metallurgy and Environment, Central South University, Hunan 410083, China
| | - Yongping Lu
- China Railway Seventh Bureau Group Nanjing Engineering Co. Ltd., Nanjing 210012, China
| | - Carlito Baltazar Tabelin
- Department of Materials and Resources Engineering and Technology, College of Engineering, Mindanao State University-Iligan Institute of Technology, Iligan City 9200, Philippines
| | - Jie Liu
- School of Metallurgy and Environment, Central South University, Hunan 410083, China
| | - Haifeng Li
- China Railway Seventh Bureau Group Nanjing Engineering Co. Ltd., Nanjing 210012, China
| | - Weichun Yang
- School of Metallurgy and Environment, Central South University, Hunan 410083, China
| | - Chongjian Tang
- School of Metallurgy and Environment, Central South University, Hunan 410083, China
| | - Xiang Feng
- Henan Academy of Geology, Henan 450001, China
| | - Jun Jiang
- School of Metallurgy and Environment, Central South University, Hunan 410083, China
| | - Shengguo Xue
- School of Metallurgy and Environment, Central South University, Hunan 410083, China.
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Li X, Zhou T, Li Z, Wang W, Zhou J, Hu P, Luo Y, Christie P, Wu L. Legacy of contamination with metal(loid)s and their potential mobilization in soils at a carbonate-hosted lead-zinc mine area. CHEMOSPHERE 2022; 308:136589. [PMID: 36162513 DOI: 10.1016/j.chemosphere.2022.136589] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 09/20/2022] [Accepted: 09/21/2022] [Indexed: 06/16/2023]
Abstract
Chemical weathering of carbonate-hosted Pb-Zn mines via acid-promoted or oxidative dissolution generates metal-bearing colloids at neutral mine drainage sites. However, the mobility and bioavailability of the colloids associated with metals in nearby soils are unknown. Here, we monitored the mobility of metal(loid)s in soils affected by aeolian deposition and river transport in the vicinity of a carbonate-hosted Pb-Zn mine. Using chemical extraction, ultrafiltration, and microscopic and spectroscopic analysis of metals we find that contamination levels of the soil metals cadmium (Cd), lead (Pb) and zinc (Zn) were negatively correlated with metal extractability. However, nano-scale characterization indicates that colloid-metal(loid) interactions induced potential mobilization and increased risk from metal(loid)s. Dynamic light scattering (DLS) and HRTEM-EDX-SAED analysis further indicate that organic matter (OM)-rich nano-colloids associated with calcium (Ca), silicon (Si) and iron (Fe) precipitates accounted for the majority of the dissolved metal fractions in carbonate-hosted Pb-Zn mine soils. More stable nano-crystals (ZnS, ZnCO3, Zn-bearing sulfates, hematite and Al-Si-Fe compounds) were present in the pore water of aeolian-impacted upland soils rather than in river water-impacted soils. Our results suggest that future work should consider the possibility that potential mobilization of metal(loid)s induced by the weathering and transformation of these metal-bearing nano-crystals to metal-bearing amorphous colloids, potentially elevating metal mobility and/or bioavailability in river water-impacted agricultural soils.
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Affiliation(s)
- Xinyang Li
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China; University of the Chinese Academy of Sciences, Beijing, 100049, China
| | - Tong Zhou
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Zhu Li
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Wenyong Wang
- Jiangsu Firefly Environmental Science and Technology Co., Ltd, Nanjing, 210046, China
| | - Jiawen Zhou
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
| | - Pengjie Hu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Yongming Luo
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Peter Christie
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China
| | - Longhua Wu
- CAS Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, China.
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Wei Y, Yuan C, Xu X, Chen X, Ren Z, Gui X, Zhao L, Qiu H, Cao X. Colloid formation and facilitated chromium transport in the coastal area soil induced by freshwater and seawater alternating fluctuations. WATER RESEARCH 2022; 218:118456. [PMID: 35447418 DOI: 10.1016/j.watres.2022.118456] [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: 02/17/2022] [Revised: 04/09/2022] [Accepted: 04/12/2022] [Indexed: 06/14/2023]
Abstract
Seawater seasonal fluctuation results in its close interaction with freshwater in the coastal area, which may affect behavior of contaminants there. This study was conducted to explore the transport and transformation of soil colloid and associated Cr during freshwater and seawater alternating fluctuations by laboratory experiment and numerical simulation. Such a fluctuation brought downward migration of Cr from upper contaminated soil and induced reduction of Cr(VI) into Cr(III). An obvious increase of retained Cr(III) was observed at the lower layers of soil due to the reducing environment. More importantly, the colloids with average sizes between 800-1500 nm was formed during the fluctuation and mainly composed of microcline and Fe/Mn oxides minerals, which determined the Cr transport. Compared with the previous freshwater fluctuation, seawater fluctuations generated more and larger-sized colloids due to its high ionic strength. These colloids carried over 94% Cr in the effluent and Cr(III) accounted for over 95% of total Cr. A colloid-facilitated Cr transport modeling showed that the soil retained Cr decreased by about 14% after eight rounds of fluctuation on an actual soil-contaminated site scale. Our study provides insight for the understanding of geochemical process of Cr in the coastal area under freshwater and seawater fluctuation conditions.
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Affiliation(s)
- Yaqiang Wei
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Chengpeng Yuan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaoyun Xu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
| | - Xiang Chen
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Zhefan Ren
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiangyang Gui
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Ling Zhao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Hao Qiu
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xinde Cao
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Engineering Research Center of Solid Waste Treatment and Resource Recovery, Shanghai Jiao Tong University, Shanghai 200240, China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, China.
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Ding Y, Wang W, Ao S. The regulating effects and mechanism of biochar and maifanite on copper and cadmium in a polluted soil- Lolium perenne L. system. PeerJ 2021; 9:e11921. [PMID: 34434656 PMCID: PMC8359803 DOI: 10.7717/peerj.11921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Accepted: 07/16/2021] [Indexed: 11/29/2022] Open
Abstract
Arable land polluted by copper (Cu) and cadmium (Cd) is a widespread problem. The use of biochar and/or clay mineral as a soil amendment can effectively solidify heavy metals in the soil. We applied biochar (BC), iron modified biochar (Fe-BC), maifanite (MF, a kind of clay minerals), a combination of BC with MF (BC:MF), and Fe-BC with MF (Fe-BC:MF) at a 2 wt % dose as soil amendments to study their ability to prevent Cu and Cd from accumulating in ryegrass (Lolium perenne L.). We found that after 90 days of cultivation, the Cd and Cu content both significantly decreased in ryegrass shoots from 2.06 and 209.3 mg kg−1 (control) to 1.44–2.01 and 51.50–70.92 mg kg−1, respectively, across treatments (p < 0.05). Similarly, the bioconcentration factor (BCF) for Cd/Cu was significantly smaller (P < 0.05) in all amendments versus control soil. This trend differed among the shoot, BCF, and transportation factor (TF). Combining BC:MF or Fe-BC:MF did not significantly improve the Cd/Cu stabilization in the soil compared to the corresponding single amendment (p > 0.05). Our adsorption balance experiment showed that BC, Fe-BC, and MF physically and chemically adsorbed Cd and Cu by complexation with functional groups (mesoporous nanomaterials) whose porosity measurements ranged from 0.68 to 78.57 m2 g−1. Furthermore, the amorphous crystalline iron oxide binding Cd and Cu was the key to immobilizing these metals in the soil. The amendments applied in our study show promise for enhancing immobilization of Cu and Cd in contaminated paddy soils.
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Affiliation(s)
- Yuan Ding
- National-Local Joint Engineering Research Center of Heavy Metal Pollutant Control and Resource Utilization, School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang, China
| | - Weiya Wang
- National-Local Joint Engineering Research Center of Heavy Metal Pollutant Control and Resource Utilization, School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang, China
| | - Shiying Ao
- National-Local Joint Engineering Research Center of Heavy Metal Pollutant Control and Resource Utilization, School of Environmental and Chemical Engineering, Nanchang Hangkong University, Nanchang, China
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Huang G, Ding C, Guo N, Ding M, Zhang H, Kamran M, Zhou Z, Zhang T, Wang X. Polymer-coated manganese fertilizer and its combination with lime reduces cadmium accumulation in brown rice (Oryza sativa L.). JOURNAL OF HAZARDOUS MATERIALS 2021; 415:125597. [PMID: 33721775 DOI: 10.1016/j.jhazmat.2021.125597] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/27/2021] [Accepted: 03/03/2021] [Indexed: 05/28/2023]
Abstract
Manganese (Mn) has the potential to reduce cadmium (Cd) uptake by rice; however, the efficiency depends on its soil availability. Therefore, this study designed a slow-release Mn fertilizer by employing a polyacrylate coating. Pot trials were conducted to study the effects of coated-Mn and uncoated-Mn alone or in combination with lime on the dynamics of soil dissolved-Mn and available Cd, and the transportation of Mn and Cd within rice. The results showed that coated-Mn declined the release of Mn until the 7th day of application; however, it consistently supplied more dissolved-Mn than uncoated-Mn. As a result, coated-Mn induced a greater Cd reduction (45.8%) in brown rice than uncoated-Mn (9.7%). The total Cd of rice and its proportion in brown rice were greatly reduced by coated-Mn, indicating the inhibition of root uptake and interior transport of Cd. Additionally, lime addition prominently increased the soil pH and decreased the CaCl2-extractable Cd (90.1-93.9%). However, since lime reduced the soil dissolved-Mn, downregulated the OsHMA3 expression and upregulated the OsNramp5 expression, brown rice Cd was reduced by only 43.0%. The combined addition of lime and coated-Mn alleviated the liming effect on soil Mn and gene expression in roots, thereby reducing brown rice Cd by 71.5%.
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Affiliation(s)
- Gaoxiang Huang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; Ministry of Education's Key Laboratory of Poyang Lake Wetland and Watershed Research, School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Changfeng Ding
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Naijia Guo
- Agricultural Ecology and Resource Protection Agency of Jiangxi Province, Nanchang 330046, China
| | - Mingjun Ding
- Ministry of Education's Key Laboratory of Poyang Lake Wetland and Watershed Research, School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China
| | - Hua Zhang
- Ministry of Education's Key Laboratory of Poyang Lake Wetland and Watershed Research, School of Geography and Environment, Jiangxi Normal University, Nanchang 330022, China
| | - Muhammad Kamran
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhigao Zhou
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Taolin Zhang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xingxiang Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, 71 East Beijing Road, Nanjing 210008, China; Ecological Experimental Station of Red Soil, Chinese Academy of Sciences, Yingtan 335211, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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6
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Huang Z, Chen Q, Yao Y, Chen Z, Zhou J. Micro-bubbles enhanced removal of diesel oil from the contaminated soil in washing/flushing with surfactant and additives. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 290:112570. [PMID: 33892234 DOI: 10.1016/j.jenvman.2021.112570] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2020] [Revised: 03/07/2021] [Accepted: 04/05/2021] [Indexed: 06/12/2023]
Abstract
Diesel removal of contaminated soil by washing/flushing was enhanced with micro-bubbles and selected surfactants based on their solubilization properties and decontamination capacities. The influencing factors were studied to aim for increasing washing/flushing efficacy. The mixture solution of saponin and cyclodextrin increased the removal efficiency significantly compared to the single-agent solution flushing with an increasing range of 20%-31%. Meanwhile, micro-bubble enhancement increased over 20% of the diesel removal for the sandy soil flushing. As the flushing process may cause soil eroded, the TDS and soil solute in flushing solution were measured to evaluate the circulation time. The 90 min flushing time ensured the cleaning goal and reserved the soil solute by circulation flushing. The soil solute, especially the electron acceptor (NO3-) , was remained in the soil, which was highly demanded for residual diesel biodegradation of loam soil. It is concluded that mixed agents, circulation of flushing solution, and micro-bubbles increased the diesel removal, and the circulation flushing could be very promising in practical applications.
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Affiliation(s)
- Zhaolu Huang
- College of Environmental Science and Engineering, Donghua University, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Shanghai Institution of Pollution Control and Ecological Security, Shanghai, 201620, China; Departments of Bioengineering, Materials Science and Engineering, University of Illinois at Urbana Champaign, Urbana, IL, 61801, USA; Illinois Sustainable Technology Center, Prairie Research Institute, University of Illinois at Urbana Champaign, Champaign, IL, 61820, USA
| | - Quanyuan Chen
- College of Environmental Science and Engineering, Donghua University, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Shanghai Institution of Pollution Control and Ecological Security, Shanghai, 201620, China.
| | - Yuan Yao
- College of Environmental Science and Engineering, Donghua University, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Shanghai Institution of Pollution Control and Ecological Security, Shanghai, 201620, China
| | - Zhao Chen
- School of Computer Science and Technology, Donghua University, Shanghai, 201620, China.
| | - Juan Zhou
- College of Environmental Science and Engineering, Donghua University, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Shanghai Institution of Pollution Control and Ecological Security, Shanghai, 201620, China
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Dinter TC, Gerzabek MH, Puschenreiter M, Strobel BW, Couenberg PM, Zehetner F. Heavy metal contents, mobility and origin in agricultural topsoils of the Galápagos Islands. CHEMOSPHERE 2021; 272:129821. [PMID: 35534959 DOI: 10.1016/j.chemosphere.2021.129821] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 01/19/2021] [Accepted: 01/30/2021] [Indexed: 06/14/2023]
Abstract
While the Galápagos Islands have been renowned for their unique flora and fauna since the time of Charles Darwin, the soils of the isolated island chain have been mostly overlooked and little information on their heavy metal contents is available. The aim of this study was therefore to examine the total heavy metal (Cd, Co, Cr, Cu, Ni, Pb, U, Zn) contents of soils from the agricultural areas on islands Isabela, Santa Cruz and San Cristóbal, and identify trends with duration of exposure to weathering processes. Additionally, the mobility of these elements was assessed using ammonium nitrate extraction. In general, levels of Cd, Co, Cr, Cu, Ni and Zn were high compared to other world locations, while Pb levels were low and U levels were similar. Ni, Co, Cr, and to a lesser extent Pb and U tended to accumulate with increasing weathering duration. Soil concentrations of Cd, Zn, Cu, and possibly Pb and U, may have been influenced by use of agrochemicals, particularly on Santa Cruz Island. Mobility of Cd displayed an increasing trend with soil age, while Ni mobility decreased. Many soils had total contents of Cd, Co, Cr, Cu, Ni and Zn above threshold values indicating possible ecological or health risks. Systematic examination of trace element contents in soils from pristine national park areas would further assist in the delineation of background levels and the development of soil quality standards to ensure crop quality, animal and human health on this unique island chain.
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Affiliation(s)
- Tamara C Dinter
- Institute of Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Martin H Gerzabek
- Institute of Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Markus Puschenreiter
- Institute of Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Bjarne W Strobel
- Department of Plant and Environmental Sciences, University of Copenhagen, Denmark
| | - Paulina M Couenberg
- Ministry of Agriculture and Livestock, Santa Cruz Island, Galápagos, Ecuador
| | - Franz Zehetner
- Institute of Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria; Galápagos National Park Directorate, Galápagos, Ecuador.
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Welikala D, Robinson BH, Moltchanova E, Hartland A, Lehto NJ. Soil cadmium mobilisation by dissolved organic matter from soil amendments. CHEMOSPHERE 2021; 271:129536. [PMID: 33445027 DOI: 10.1016/j.chemosphere.2021.129536] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Revised: 12/18/2020] [Accepted: 01/01/2021] [Indexed: 06/12/2023]
Abstract
Dissolved organic matter (DOM) release from Cd contaminated soils been linked to mobilisation of the metal as Cd-DOM complexes and this may be exacerbated by organic matter-rich soil amendments. The quantity and quality of the DOM can determine the proportion of dissolved Cd that partitions to mobile complexes and their stability and, thus, the potential for Cd transport from contaminated soils. The aim of this work was to examine differences in Cd mobilisation from soils to which different types of soil amendments/conditioners have been applied and the importance of DOM characteristics in determining the extent to which this can happen. Three soils were spiked with Cd to 2 mg kg-1, allowed to equilibrate and then treated with compost and peat. These soils and an untreated subsample of each soil were then adjusted to three different pHs: 5.6, 6.4 and 7.4, using lime. The amount of Cd mobilised from each soil was tested using a column leaching experiment. Ultrafiltration and speciation modelling were used to determine amounts of Cd as DOM-complexed, "truly" dissolved (<5 kDa) and colloidal species, while DOM quality was assessed using UV-Vis and fluorescence spectroscopy. Most colloidal Cd was mobilised from the compost treated soils (50%-60%), followed by the peat treated soils (20-44%). The relationships between colloidal Cd, DOC concentration and soil pH, together with the spectroscopic and modelling results showed that structural properties of DOM are an important factor in mobilising Cd from contaminated soils.
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Affiliation(s)
- Dharshika Welikala
- Department of Soil and Physical Sciences, Lincoln University, Lincoln, 7647, Christchurch, New Zealand
| | - Brett H Robinson
- School of Physical and Chemical Sciences, University of Canterbury, New Zealand
| | - Elena Moltchanova
- School of Mathematics and Statistics, University of Canterbury, New Zealand
| | - Adam Hartland
- Environmental Research Institute, School of Science, University of Waikato, Private Bag 3105, Hamilton, 3240, New Zealand
| | - Niklas J Lehto
- Department of Soil and Physical Sciences, Lincoln University, Lincoln, 7647, Christchurch, New Zealand.
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