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Youssef M, Otaibi SA, El-Sorogy AS. Distribution, Source, and Contamination of Heavy Metals in Coastal Sediments of Jeddah, Red Sea, Saudi Arabia. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2024; 113:12. [PMID: 39009950 DOI: 10.1007/s00128-024-03923-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 06/20/2024] [Indexed: 07/17/2024]
Abstract
The study investigates heavy metal (HM) contamination in coastal sediments of Jeddah along Red Sea coast, analyzing spatial distribution and sources. 24 samples underwent (ICP-AES) for Fe, Al, Mn, Ni, Pb, Zn, Cu, Cr, Co, Sr, V, and As. HM averages followed Fe ˃ Al ˃ Sr ˃ Mn ˃ Zn ˃ V ˃ Cu ˃ Ni ˃ Cr ˃ As ˃ Co ˃ Pb. Contamination indices revealed severe Sr enrichment, minor As and Co enrichment, and no enrichment for other HMs. Sediment quality guidelines suggest Ni, Cu, Zn, and As risks to benthic communities at some sites, while Cr and Pb pose minimal risk. Multivariate analysis indicates natural sources for Fe, Al, Mn, Ni, Zn, Cu, Cr, Co, and V, and anthropogenic sources for Sr, As, and Pb, linked to agriculture, industry, and urbanization. Increased Sr values may stem from seawater acidification impacting calcitic corals and molluscs.
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Affiliation(s)
- Mohamed Youssef
- Geology and Geophysics Department, College of Science, King Saud University, Riyadh, Saudi Arabia.
| | - Sami Al Otaibi
- Department of soil Science, College of Food & Agriculture Sciences, king Saud University, Riyadh, Saudi Arabia
| | - Abdelbaset S El-Sorogy
- Geology and Geophysics Department, College of Science, King Saud University, Riyadh, Saudi Arabia
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2
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Alam MA, Mukherjee A, Bhattacharya P, Bundschuh J. An appraisal of the principal concerns and controlling factors for Arsenic contamination in Chile. Sci Rep 2023; 13:11168. [PMID: 37429943 DOI: 10.1038/s41598-023-38437-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2023] [Accepted: 07/07/2023] [Indexed: 07/12/2023] Open
Abstract
Although geogenic Arsenic (As) contamination is well-recognized in northern Chile, it is not restricted to this part of the country, as the geological conditions favoring As release to the human environment exist across the country as well, although not at the same level, based on comparatively fewer studies in central and southern Chile. The present work provides a critical evaluation of As sources, pathways, and controls with reports and case studies from across the country based on an exhaustive bibliographic review of its reported geogenic sources and processes that affect its occurrence, systematization, and critical revision of this information. Arc magmatism and associated geothermal activities, identified as the primary As sources, are present across the Chilean Andes, except for the Pampean Flat Slab and Patagonian Volcanic Gap. Metal sulfide ore zones, extending from the country's far north to the south-central part, are the second most important geogenic As source. While natural leaching of As-rich mineral deposits contaminates the water in contact, associated mining, and metallurgical activities result in additional As release into the human environment through mining waste and tailings. Moreover, crustal thickness has been suggested as a principal controlling factor for As release, whose southward decrease has been correlated with lower As values.
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Affiliation(s)
- Mohammad Ayaz Alam
- Departamento de Ingeniería Geoespacial y Ambiental, Facultad de Ingeniería, Universidad de Santiago de Chile, Enrique Kirberg Baltiansky n° 03, Estación Central, Santiago, Región Metropolitana, Chile.
| | - Abhijit Mukherjee
- Department of Geology and Geophysics, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal, India
| | - Prosun Bhattacharya
- KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Stockholm, Sweden
| | - Jochen Bundschuh
- School of Engineering, Faculty of Health, Engineering and Sciences, University of Southern Queensland, West Street, Toowoomba, Queensland, Australia
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Valdés J, Ortlieb L, Sifeddine A, Castillo A. Human-induced metals accumulation in sediments of an industrialized bay of northern Chile. An enrichment and ecological risk assessment based on preindustrial values. MARINE POLLUTION BULLETIN 2023; 189:114723. [PMID: 36848787 DOI: 10.1016/j.marpolbul.2023.114723] [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: 11/23/2022] [Revised: 02/01/2023] [Accepted: 02/09/2023] [Indexed: 06/18/2023]
Abstract
Environmental assessment in marine systems is difficult because most of the time their preindustrial characteristics are not available. Four sediment cores taken in Mejillones bay (northern Chile) were used to establish preindustrial metals concentrations, and to assess the environmental status of this industrialized zone. According to historical documents, the beginning of the industrial era start in 1850 CE. Considering this, the preindustrial concentration of some metals was established, by mean of a statistical approach. Most of the metals increase their concentration from the preindustrial to the industrial period. Environmental assessment showed an enrichment of Zr and Cr, a moderately polluted condition, and a low probability of toxic effect on the biological communities. The preindustrial values derived from sediment cores are a good tool to evaluate the environmental condition of Mejillones bay. However new information (backgrounds with a higher spatial representativity, toxicological threshold, and others) it is necessary to improve the environmental assessment of this environment.
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Affiliation(s)
- J Valdés
- Laboratorio de Sedimentología y Paleoambientes (LASPAL), Instituto de Ciencias Naturales Alexander von Humboldt, Facultad de Ciencias del Mar y de Recursos Biológicos, Universidad de Antofagasta, Chile.
| | - Luc Ortlieb
- LOCEAN - IPSL UMR 7159, Institut de Recherche pour le Developpement-Sorbonne Université (Université P. et M. Curie, Paris 06)-CNRS/UPMC/IRD, IRD, France
| | - A Sifeddine
- LOCEAN - IPSL UMR 7159, Institut de Recherche pour le Developpement-Sorbonne Université (Université P. et M. Curie, Paris 06)-CNRS/UPMC/IRD, IRD, France; ERC2-Université de Quisqueya-Port au Prince, Haiti
| | - A Castillo
- Centro de Investigación y Estudios Avanzados del Maule, Vicerrectoría de Investigación y Posgrado, Universidad Católica del Maule, Campus San Miguel, Talca, Chile; J'EAI-CHARISMA (UMNG-Colombia, UPCH-Perú, IGP-Peru, UCM-Chile, UCh-Chile, UA-Chile, IRD-France), Colombia; ANID-Millenium Science Initiative Program Nucleo Milenio UPWELL, La Serena, Chile
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Carmona B, Abejón R. Innovative Membrane Technologies for the Treatment of Wastewater Polluted with Heavy Metals: Perspective of the Potential of Electrodialysis, Membrane Distillation, and Forward Osmosis from a Bibliometric Analysis. MEMBRANES 2023; 13:385. [PMID: 37103812 PMCID: PMC10145262 DOI: 10.3390/membranes13040385] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 03/20/2023] [Accepted: 03/26/2023] [Indexed: 06/19/2023]
Abstract
A bibliometric analysis, using the Scopus database as a source, was carried out in order to study the scientific documents published up to 2021 regarding the use of electrodialysis, membrane distillation, and forward osmosis for the removal of heavy metals from wastewater. A total of 362 documents that fulfilled the search criteria were found, and the results from the corresponding analysis revealed that the number of documents greatly increased after the year 2010, although the first document was published in 1956. The exponential evolution of the scientific production related to these innovative membrane technologies confirmed an increasing interest from the scientific community. The most prolific country was Denmark, which contributed 19.3% of the published documents, followed by the two main current scientific superpowers: China and the USA (with 17.4% and 7.5% contributions, respectively). Environmental Science was the most common subject (55.0% of contributions), followed by Chemical Engineering (37.3% of contributions) and Chemistry (36.5% of contribution). The prevalence of electrodialysis over the other two technologies was clear in terms of relative frequency of the keywords. An analysis of the main hot topics identified the main advantages and drawbacks of each technology, and revealed that examples of their successful implementation beyond the lab scale are still scarce. Therefore, complete techno-economic evaluation of the treatment of wastewater polluted with heavy metals via these innovative membrane technologies must be encouraged.
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Affiliation(s)
- Benjamín Carmona
- Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile (USACH), Av. Libertador Bernardo O'Higgins 3363, Estación Central, Santiago 9170019, Chile
| | - Ricardo Abejón
- Departamento de Ingeniería Química y Bioprocesos, Universidad de Santiago de Chile (USACH), Av. Libertador Bernardo O'Higgins 3363, Estación Central, Santiago 9170019, Chile
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Tapia J, Mukherjee A, Rodríguez MP, Murray J, Bhattacharya P. Role of tectonics and climate on elevated arsenic in fluvial systems: Insights from surface water and sediments along regional transects of Chile. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120151. [PMID: 36115482 DOI: 10.1016/j.envpol.2022.120151] [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: 06/27/2022] [Revised: 09/03/2022] [Accepted: 09/06/2022] [Indexed: 06/15/2023]
Abstract
Globally, arsenic (As) contamination is widespread in hydrological systems and the link between As enrichment and regional tectonic and climatic factors is still not well understood in orogenic environments. This work provides new insights on the relationship between As, tectonics, and climate by assessing the hydrochemistry of Chile, an active subduction zone with highly diverse natural settings. Selected study sites include fluvial courses along four regional transects connecting the Chilean coast to the Andes Cordillera in the northern, central, and southern areas of the country. The results indicate that As concentrations in surface water and fluvial sediments show a general positive correlation to crustal thickness and they tend to decrease progressively from northern to southern Chile. In contrast, As concentrations are negatively correlated to average annual precipitation which shows a significant increase toward southern Chile. From a regional tectonic perspective, northern Chile presents greater Andes shortening and higher crustal thicknesses, which induces increased crustal contamination and As content at the surface. Extremely low precipitation rates are also tied to local As enrichment and a sediment-starved trench that might favor higher plate coupling and shortening. On the contrary, decreased shortening of the Andes in southern Chile and related lower crustal thickness induces lower crustal contamination, thus acting as an As-poor provenance for surficial sediments and surface water. High precipitation rates further induce dilution of surface water, potential mobilization from the solid phase, and a significant amount of trench sediments that could induce lower plate coupling and lower shortening. At the local scale, a low potential for As mobilization was found in northern Chile where a greater distribution of As-bearing minerals was observed in sediments, mostly as finer particles (<63 μm). The abundance of Fe-oxides potentially acts as a secondary surficial sink of As under the encountered physicochemical conditions.
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Affiliation(s)
- Joseline Tapia
- Departamento de Ciencias Geológicas, Universidad Católica Del Norte, Antofagasta, Chile; Centro de Estudio Del Agua Del Desierto, CEITSAZA, Universidad Católica Del Norte, Antofagasta, Chile; Instituto Milenio de Investigación en Riesgo Volcánico - CKELAR Volcanoes, Chile.
| | - Abhijit Mukherjee
- Department of Geology and Geophysics, Indian Institute of Technology-Kharagpur, Kharagpur, 721302, West Bengal, India
| | | | - Jesica Murray
- Instituto de Bio y Geociencias Del NOA, CONICET-Universidad Nacional de Salta, Salta, Argentina; Institute of the Earth and the Environment of Strasbourg, University of Strasbourg, France
| | - Prosun Bhattacharya
- KTH-International Groundwater Arsenic Research Group, Department of Sustainable Development, Environmental Science and Engineering, KTH Royal Institute of Technology, Teknikringen, 10B, SE-114 28, Stockholm, Sweden
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Bonnail E, Díaz-García A, Cruces E, García A, Borrero-Santiago AR. Coastal uses and contaminant spread in the desert coastal region of Atacama. CHEMOSPHERE 2022; 288:132519. [PMID: 34637862 DOI: 10.1016/j.chemosphere.2021.132519] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 10/06/2021] [Accepted: 10/07/2021] [Indexed: 06/13/2023]
Abstract
Ocean contamination mostly comes from anthropogenic contamination in watercourses. However, what happens in desert areas where watercourses are few or nonexistent? Are these coastal areas exempt from contamination? Do the remote locations of desert areas enable pristine coastal areas? Atacama is widely known for its desert aridity and mining resources; however, human impacts in its coastal areas have not been widely studied. Coastal zone uses of this region of Chile were analyzed per province in relation to the population settlements and economic activities on the coastal edge. This study includes a review of the contamination in this desert coastal area in relation to the territorial organization, activities, and land uses. The results determined that most of the coastal edge was used for fishing and aquaculture (52%) and for conservation and protected areas (39%). However, 2% of the coastal edge was susceptible to conflicts due to shared uses. A strong lack of scientific research was detected despite environmental interest (Humboldt Current, diversity hot spots, desert blooming, algae kelps, protected areas, etc.) and economic development (impact of mining, agriculture and tourism) in the area. Most studies focused on metal concentrations in aquatic environments in the north part of the region. Studies on emerging contaminants have not been carried out in the area despite intense human settlement.
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Affiliation(s)
- Estefanía Bonnail
- Centro de Investigaciones Costeras-Universidad de Atacama (CIC-UDA), Avenida Copayapu 485, Copiapó, Atacama, Chile.
| | | | - Edgardo Cruces
- Centro de Investigaciones Costeras-Universidad de Atacama (CIC-UDA), Avenida Copayapu 485, Copiapó, Atacama, Chile
| | - Ayón García
- Instituto de Investigaciones Científicas y Tecnológicas de la Universidad de Atacama (IDICTEC-UDA), Avenida Copayapu 485, Copiapó, Chile
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Zárate A, Dorador C, Valdés J, Molina V, Icaza G, Pacheco AS, Castillo A. Benthic microbial diversity trends in response to heavy metals in an oxygen-deficient eutrophic bay of the Humboldt current system offshore the Atacama Desert. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 286:117281. [PMID: 33992902 DOI: 10.1016/j.envpol.2021.117281] [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: 11/20/2020] [Revised: 03/25/2021] [Accepted: 04/27/2021] [Indexed: 06/12/2023]
Abstract
Mejillones Bay is a coastal ecosystem situated in an oxygen-deficient upwelling area impacted by mining activities in the coastal desert region of northern Chile, where conspicuous microbial life develops in the sediments. Herein, heavy metal (loid)s (HMs) such as Cu, Pb, As, Zn, Al, Fe, Cd, Mo, Ni and V as well as benthic microbial communities were studied using spectrometry and iTag-16 S rRNA sequencing. Samples were taken from two contrasting sedimentary localities in the Bay named Punta Rieles (PR) and Punta Chacaya (PC) within 10-50 m water-depth gradient. PR sediments were organic matter rich (21.1% of TOM at 50 m) and overlaid with low-oxygen waters (<0.06 ml O2/L bottom layer) compared with PC. In general, HMs like Al, Ni, Cd, As and Pb tended to increase in concentration with depth in PR, while the opposite pattern was observed in PC. In addition, PR presented a higher number of unique families (72) compared to PC (35). Among the top ten microbial families, Desulfobulbaceae (4.6% vs. 3.2%), Flavobacteriaceae (2.8% vs. 2.3%) and Anaerolineaceae (3.3% vs. 2.3%) dominated in PR, meanwhile Actinomarinales_Unclassified (8.1% vs. 4.2%) and Sandaracinaceae (4.4% vs. 2.0%) were more abundant in PC. Multivariate analyses confirmed that water depth-related variation was a good proxy for oxygen conditions and metal concentrations, explaining the structure of benthic microbial assemblages. Cd, Ni, As and Pb showed uniformly positive associations with communities that represented the keystone taxa in the co-occurrence network, including Anaerolineaceae, Thiotrichaceae, Desulfobulbaceae, Desulfarculaceae and Bacteroidales_unclassified communities. Collectively, these findings provide new insights for establishing the ecological interconnections of benthic microorganisms in response to metal contamination in a coastal upwelling environment.
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Affiliation(s)
- Ana Zárate
- Doctorado en Ciencias Aplicadas Mención Sistemas Marinos Costeros, Universidad de Antofagasta, Antofagasta, Chile; Laboratorio de Complejidad Microbiana y Ecología Funcional, Instituto Antofagasta & Centro de Bioingeniería y Biotecnología (CeBiB), Universidad de Antofagasta, Antofagasta, Chile; Humedales Del Caribe Colombiano, Universidad Del Atlántico, Barranquilla, Colombia.
| | - Cristina Dorador
- Laboratorio de Complejidad Microbiana y Ecología Funcional, Instituto Antofagasta & Centro de Bioingeniería y Biotecnología (CeBiB), Universidad de Antofagasta, Antofagasta, Chile; Departamento de Biotecnología, Facultad de Ciencias Del Mar y Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Jorge Valdés
- Laboratorio de Sedimentología y Paleoambientes, Instituto de Ciencias Naturales A. von Humboldt, Facultad de Ciencias Del Mar y de Recursos Biológicos, Universidad de Antofagasta, Antofagasta, Chile
| | - Verónica Molina
- Departamento de Biología, Observatorio de Ecología Microbiana, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile; HUB Ambiental UPLA, Universidad de Playa Ancha, Valparaíso, Chile
| | - Gonzalo Icaza
- Laboratorio de Complejidad Microbiana y Ecología Funcional, Instituto Antofagasta & Centro de Bioingeniería y Biotecnología (CeBiB), Universidad de Antofagasta, Antofagasta, Chile
| | - Aldo S Pacheco
- Facultad de Ciencias Biológicas, Universidad Nacional Mayor de San Marcos, Lima, Peru
| | - Alexis Castillo
- Centro de Investigación y Estudios Avanzados Del Maule. Vicerrectoría de Investigación de Investigación y Posgrado. Universidad Católica Del Maule, Campus San Miguel. Talca, Chile
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Marambio-Alfaro Y, Saavedra JV, Enciso LÑ, Marras AL, Serrano AE, Peláez RM, Bruna AC, Ávalos GÁ, Maldonado MV. Microlophus atacamensis as a biomonitor of coastal contamination in the Atacama Desert, Chile: An evaluation through a non-lethal technique. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 269:115739. [PMID: 33279265 DOI: 10.1016/j.envpol.2020.115739] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2020] [Revised: 09/12/2020] [Accepted: 09/25/2020] [Indexed: 06/12/2023]
Abstract
In this report, we investigated the accumulation of heavy metals in the lizard Microlophus atacamensis, in three coastal areas of the Atacama Desert, northern Chile. We captured reptiles in a non-intervened area (Parque Nacional Pan de Azúcar, PAZ), an area of mining impact (Caleta Palitos, PAL) and an active industrial zone (Puerto de Caldera, CAL). Our methods included a non-lethal sampling of reptiles' tails obtained by autotomy and a few sacrificed animals to perform a stomach contents analysis. The concentrations of lead, copper, nickel, zinc and cadmium were measured by atomic absorption spectrophotometry in both soil and prey and compared to those recorded in the lizards' tails. Data obtained from lizard tails captured in PAL showed significantly high concentrations of Pb, Cu, Ni, and Zn compared to the other two sites PAZ and CAL. We did not find statistically significant differences among PAZ, PAL and CAL soils, probably due to the similar geological composition of the sites. However, the regional background values for Pb indicate contamination or at least metal enrichment in soils of the three sites, for Cu the global background values indicate contamination for the three sites, and for Cd both the regional and global backgroud values show high values. The analysis of the stomach content showed differences in the food sources of the lizards among the sites studied. The concentration of heavy metal in lizard tissues versus prey delivered values of the Trophic Transfer Factor higher than one (1), suggesting that food may be a primary source of metals in the tissues of M. atacamensis. Calculations of the Bioaccumulation Factor (BAF) and the Ecological Risk (IR) resulted in values higher than one (1) indicating the relevance of this process in the sites studied. In this article, we report relationships between environmental contaminants, mainly putative preys, and concentrations found in lizard tails, which is more substantial in areas with historical heavy metal contamination such as PAL where the non-lethal technique developed in this research suggests a process of metal bioaccumulation in M. atacamensis.
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Affiliation(s)
- Yery Marambio-Alfaro
- LASPAL-LABIGAM Laboratories, Alexander von Humboldt Institute of Natural Sciences. University of Antofagasta, Antofagasta, 1240000, Chile; Parménides Limited, 1265 Plaza Wheelwright. Copiapó, 1530291, Atacama, Chile; Doctoral Program in Applied Sciences - Coastal Marine Systems, Faculty of Marine Sciences and Biological Resources. University of Antofagasta, Antofagasta, 1240000, Chile.
| | - Jorge Valdés Saavedra
- LASPAL-LABIGAM Laboratories, Alexander von Humboldt Institute of Natural Sciences. University of Antofagasta, Antofagasta, 1240000, Chile
| | - Luis Ñacari Enciso
- Doctoral Program in Applied Sciences - Coastal Marine Systems, Faculty of Marine Sciences and Biological Resources. University of Antofagasta, Antofagasta, 1240000, Chile
| | - Américo López Marras
- LASPAL-LABIGAM Laboratories, Alexander von Humboldt Institute of Natural Sciences. University of Antofagasta, Antofagasta, 1240000, Chile
| | | | - Rodrigo Martínez Peláez
- Department of Mathematics, Faculty of Basic Sciences, University of Antofagasta, Antofagasta, 1240000, Chile
| | - Alexis Castillo Bruna
- Research Centre for Advanced Studies of Maule, Vice-Rector's Office for Research and Postgraduate Studies, Catholic University of Maule, San Miguel Campus, San Miguel Av., Talca, Chile
| | - Gabriel Álvarez Ávalos
- Department of Engineering in Geo Measuring and Geomatics. University of Antofagasta, Antofagasta, 1240000, Chile
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Migration and Diffusion of Heavy Metal Cu from the Interior of Sediment during Wave-Induced Sediment Liquefaction Process. JOURNAL OF MARINE SCIENCE AND ENGINEERING 2019. [DOI: 10.3390/jmse7120449] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Sediments are an important sink for heavy metal pollutants on account of their strong adsorption capacity. Elevated content of Cu was observed in the Chengdao area of the Yellow River Delta, where the surface sediment is mainly silt and is prone to be liquefied under hydrodynamic forces. The vertical transport of fine particles, along with pore water seepage, during the liquefaction process could promote the migration and diffusion of Cu from the interior of sediment. The present study involved a series of wave flume experiments to simulate the migration and diffusion of Cu from the interior of sediment in the subaqueous Yellow River Delta area under wave actions. The results indicated that sediment liquefaction significantly promoted the release of Cu from internal sediment to overlying water. The variations of Cu concentrations in the overlying water were opposite to the suspended sediment concentrations (SSCs). The sediment liquefaction caused high initial rises of SSCs, but led to a rapid decline of dissolved Cu concentration at the initial period of sediment liquefaction due to the adsorption by fine particles. Afterwards, the SSCs slightly increased and then gradually decreased. Meanwhile, the dissolved Cu concentration generally kept increasing under combined effects of intensively mix of sediment and overlying water, pore water seepage, and desorption. The dissolved Cu concentration in the overlying water during sediment liquefaction phase was 1.5–2.2 times that during the consolidation phase. Sediment liquefaction also caused vertical diffusion of Cu in sediment and the diffusion depth was in accordance with the liquefaction depth. The results of the present study may provide reference for the environmental management in the study area.
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