Journal of Geochemical Exploration最新文献

{"title":"Uptake and toxicity of heavy metals: The protective frontiers of metal binding proteins","authors":"Ravneet Kaur,&nbsp;Harleen Kaur,&nbsp;Ashish Sharma","doi":"10.1016/j.gexplo.2025.107673","DOIUrl":"10.1016/j.gexplo.2025.107673","url":null,"abstract":"<div><div>In environment, several contaminants and pollutants are released, the content of which is increasing alarmingly. Out of several contaminants released into environment, one such contaminant is heavy metals. Such contaminants being released into the environment then enter into plant system via soil. Plants uptake heavy metals from soil via apoplast symplast continuum. Plant require several nutrients in minute concentrations however presence of such nutrients in excess cause toxic effects on plants. Such heavy metals caused varied toxicities such as chlorosis, impaired photosynthesis, lipid peroxidation etc. in plants resulting in overall decline in plant biomass. Excess concentration of heavy metals such as copper, chromium, nickel are known to induce morphological, physiological deformities in several plant species. In response to ROS generated due to heavy metal toxicity, plants activate several defense mechanisms. In addition to this, several metal binding proteins such as metallothioneins, phytochelatins, glutathione etc. are activated. These metal binding protein act to reduce the toxic effects of heavy metals by binfing to them and sequestering then into vacuoles. The current review will highlight the uptake mechanism of heavy metals by plants, toxicity caused by some commonly occurring heavy metals in plants and role of metal binding proteins in sequestering such heavy metals.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"271 ","pages":"Article 107673"},"PeriodicalIF":3.4,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Using principal component analysis to distinguish sources of radioactivity and nitrates contamination in Southern Tunisian groundwater samples","authors":"Tiziano Boschetti ,&nbsp;Younes Hamed ,&nbsp;Rihab Hadji ,&nbsp;Maurizio Barbieri ,&nbsp;Matteo Gentilucci ,&nbsp;Mattia Rossi ,&nbsp;Rayan Khalil ,&nbsp;Shuhab D. Khan ,&nbsp;Bassem Asghar ,&nbsp;Abdulrasoul Al-Omran ,&nbsp;Elimame Elaloui","doi":"10.1016/j.gexplo.2025.107670","DOIUrl":"10.1016/j.gexplo.2025.107670","url":null,"abstract":"<div><div>The manuscript discusses using Principal Component Analysis (PCA) to distinguish the sources of radioactive and nitrate contamination in 33 groundwater samples from southern Tunisia. The study focuses on the Gafsa basin, an area known for its phosphate mining activities and significant agricultural use, both of which contribute to the contamination of groundwater resources. The radioactivity in the water is primarily attributed to phosphate mining and deep groundwater sources from the North Western Sahara Aquifer System (NWSAS). Additionally, the nitrate contamination is largely due to agricultural runoff, though secondary sources related to phosphate mining are also considered.</div><div>Through the application of PCA, the study was able to classify the groundwater samples into different groups based on their contamination sources: phosphate mining, combined agricultural and mining activities, fossil geothermal waters, and low-agricultural areas. The PCA revealed that samples most affected by anthropogenic activities exhibited high levels of radium and nitrate, with contamination patterns correlating with specific environmental and chemical factors.</div><div>This analysis underscores the complexity of groundwater contamination in the region and highlights the need for targeted mitigation strategies to address radioactive and nitrate pollution in southern Tunisia. The study provides critical insights for managing water quality in areas with similar environmental challenges.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"271 ","pages":"Article 107670"},"PeriodicalIF":3.4,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143181101","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Corrigendum to “Assessment of potentially toxic elements in some wild edible plants of district Doda, Jammu and Kashmir, India” [J. Geochem. Explor. 267, p. 107604. (Dec 2024)]","authors":"Sania Hamid ,&nbsp;Devendra Kumar Pandey ,&nbsp;Deepika Singh","doi":"10.1016/j.gexplo.2024.107668","DOIUrl":"10.1016/j.gexplo.2024.107668","url":null,"abstract":"","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107668"},"PeriodicalIF":3.4,"publicationDate":"2024-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Vectoring towards buried high-purity quartz metapegmatites using low-elevation radiometric and soil geochemical surveying: Method validation in Tysfjord, Norway","authors":"Mario Hopfner ,&nbsp;Marco Brönner ,&nbsp;Lawrence Carter ,&nbsp;Teimoor Nazari-Dehkordi ,&nbsp;Julian Menuge ,&nbsp;Axel Müller ,&nbsp;Ben Williamson","doi":"10.1016/j.gexplo.2024.107667","DOIUrl":"10.1016/j.gexplo.2024.107667","url":null,"abstract":"<div><div>Group 2/NYF pegmatites may be economically enriched in rare minerals. In this study we report testing of two exploration methods, gamma ray surveying and soil geochemical mapping, undertaken within the GREENPEG project. Palaeoproterozoic metapegmatites in the Tysfjord area, Nordland, Norway, include some which have been mined for pure quartz. Geologically, the ore zones are the quartz cores of metapegmatites whose other zones and metasomatic halos are enriched in U, Th, REE, Nb and other rare elements. The Jennyhaugen metapegmatite was the main test site because its subcrop beneath 0.1–1.0 m soil can be traced from an open pit mine, and aerial surveying is unobstructed by trees. Helicopter-borne radiometry at 60 m altitude and drone-borne radiometry at 25–35 m altitude detect the metapegmatite, while walking (1.0 or 1.6 m height) and 15 m altitude drone-borne radiometry resolve the metapegmatite and metasomatic halo subcrop in detail. Total gamma ray count measurements provide as good an exploration tool as Th or U radiation; K radiation does not show useful anomalies. Both A- and C-horizon soil geochemical mapping also reveal U, Th, Nb and other geochemical anomalies above metapegmatite and halo subcrop. A-horizon soil samples appear to more accurately locate these targets, perhaps because they effectively sample larger surface areas of subcropping rock, whose grain size is very coarse (typically metre scale) within the metapegmatite. C-horizon samples collected from the soil-rock interface are less likely to be representative of the metapegmatite. Gamma ray surveying is recommended rather than soil chemical mapping for exploration, by helicopter at district scale and by drone or walking at prospect scale. It is quicker, requires less field workers, has higher resolution and is less expensive than soil geochemical mapping. Soil chemistry may be preferred for prospect-scale exploration, however, where the commodity sought does not spatially correlate with U and/or Th concentrations.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107667"},"PeriodicalIF":3.4,"publicationDate":"2024-12-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ore-forming processes of giant carbonate-hosted ZnPb deposit and Ge enrichment mechanism in Zhugongtang, Guizhou Province, China: Constraints from trace element and isotopic compositions of sulfides","authors":"Qing Yang ,&nbsp;Shao-Yong Jiang ,&nbsp;Suo-Fei Xiong ,&nbsp;Jun-Jie Hou","doi":"10.1016/j.gexplo.2024.107666","DOIUrl":"10.1016/j.gexplo.2024.107666","url":null,"abstract":"<div><div>The Zhugongtang Zn<img>Pb deposit, with &gt;3.27 million tons of Zn + Pb averaging 6.76 % Zn and 2.27 % Pb, along with 592 tons of Ge, is a newly discovered giant Zn<img>Pb deposit in northwest Guizhou Province of the Sichuan-Yunnan-Guizhou metallogenic region, Southwest China. This deposit is hosted in Devonian, Carboniferous, and Permian carbonate rocks. Three stages of hydrothermal mineralization were identified: (1) the pyrite-sphalerite-quartz stage, (2) the sphalerite-galena-pyrite-calcite stage, and (3) the carbonate stage, and three generations of sphalerite (Sp-1, Sp-2, and Sp-3) were identified. In this study, analyses of in situ trace element compositions in sphalerite and S<img>Pb isotopic compositions of sulfides were conducted to determine the origin and mineralization processes of the Zhugongtang deposit. Sphalerite is characterized by enrichment of Ge (mean = 109 ppm), Cd (mean = 875 ppm), and Ga (mean = 30 ppm) and depletion of In, Sn, and Co, with increasing Ge and Cu and decreasing Mn, Ag and Pb from the early to late stages. Ge incorporates into sphalerite via a coupled substitution of 3Cu⁺ + Sb³⁺ + Ge⁴⁺ ↔ 5Zn²⁺. The temperature and sulfur fugacity (<em>f</em>S₂) are estimated from the trace element concentrations in sphalerite, which indicate medium- to low-temperature and intermediate-sulfidation conditions with decreasing temperature and <em>f</em>S₂ from Sp-1 to Sp-3. The pyrite, sphalerite, and galena have δ³⁴S values ranging from 11.3 to 17.8 ‰, 10.2 to 17.3 ‰, and 8.4 to 14.7 ‰, respectively, indicating that the reduced sulfur likely originated from the thermochemical reduction of sulfate (TSR) with multiple sources. High-precision in situ Pb isotope ratios of ²⁰⁸Pb/²⁰⁴Pb, ²⁰⁷Pb/²⁰⁴Pb, and ²⁰⁶Pb/²⁰⁴Pb range from 39.609 to 40.230, 15.860 to 16.042, and 18.768 to 18.984, respectively, which implies that the lead was sourced primarily from the host rock and basement strata. On the basis of a comprehensive analysis of ore geology and geochemical data, the Zhugongtang deposit is classified as an MVT deposit. With the gradual decrease in temperature and <em>f</em>S₂, sphalerite (Sp-2 and Sp-3) precipitated in large quantities with significant enrichment of Ge (mean 147 ppm).</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107666"},"PeriodicalIF":3.4,"publicationDate":"2024-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164047","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Global distribution and sources of uranium and fluoride in groundwater: A comprehensive review","authors":"C.N. Sridhar ,&nbsp;M. Thirumurugan ,&nbsp;T. Subramani ,&nbsp;P. Gopinathan","doi":"10.1016/j.gexplo.2024.107665","DOIUrl":"10.1016/j.gexplo.2024.107665","url":null,"abstract":"<div><div>Contamination of elements in water due to geogenic and anthropogenic activities is common around the world. Intake of contaminated water causes severe health hazards to the living community. To avoid the health hazards, World Health Organisation (WHO) has specified certain limit of the level of elements as well as ions present in the water for drinking purpose. Some common chemical contaminates in the groundwater are Uranium (U) and Fluoride (Fˉ). The intake of groundwater which is having excess amount of Uranium (U) and Fluoride (Fˉ) may lead to serious health issues. The permissible level of Uranium in water as is 30 ppb as per WHO, but in some regions due to the rock type, mining activity, chemical waste; the level of U present in water might be higher than the prescribed limit and its consumption may cause carcinogenic and non-carcinogenic diseases. As like Uranium, Fluoride has certain limit fixed by WHO that is 1.5 ppm. If the level of Fˉ is higher than 1.5 ppm it may cause dental fluorosis and skeletal fluorosis. To reduce the health risks due to intake of the elements or ions, the contaminated groundwater needs to be monitored and treated by means of constructing artificial recharge structures and other rainwater harvesting methods. However, certain ex-situ processes like membrane method, ion exchange, adsorption, and precipitation may be adopted to reduce or remove the contaminated elements/ions in the groundwater.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107665"},"PeriodicalIF":3.4,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164551","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hydrochemical processes and water balance trends based on stable isotopes of typical alpine lakes in the Qinghai-Tibet Plateau","authors":"Changchang Fu ,&nbsp;Xiangquan Li ,&nbsp;Xu Cheng ,&nbsp;Cong Liu ,&nbsp;Zhanxue Bai ,&nbsp;Jinqiu Li","doi":"10.1016/j.gexplo.2024.107663","DOIUrl":"10.1016/j.gexplo.2024.107663","url":null,"abstract":"<div><div>Due to the warming climate, the hydrological cycle of the Qinghai-Tibet Plateau (QTP) is accelerating, leading to continuous growth of alpine lakes. In case of overflow, this can pose significant risks to downstream water quality and resources. However, there is a lack of comprehensive investigations on the chemical composition and water balance of lakes in QTP. This study examines the evolutionary mechanisms of alpine lakes in the Yanhu Lake Basin (YHB) located in central QTP. It investigates stable isotopes (<em>δ</em>¹⁸O and δD), hydrochemistry, and utilizes the isotope balance model to determine the evaporation to inflow (E/I) ratio of lake water. The findings reveal that lake water exhibits a Cl<img>Na hydrochemical type with enrichment in total dissolved solids (TDS), boron (B), and lithium (Li) elements. On the δD- <em>δ</em>¹⁸O plot, lake water falls below the Local Meteoric Water Line (LMWL) towards rightward direction with a slope of 4.75 and an intercept of 11.83, indicating pronounced evaporation characteristics. The presence of more positive isotope signals and ratios among major ions suggests that evaporation processes primarily govern lake water's hydrochemistry. The modeled E/I ratio ranges from 0.19 to 0.65 across YHB, implying a positive lake water balance which contributes to consistent expansion in surface area. This highlights the need for local government to enhance monitoring efforts, closely observe fluctuations in Yanhu Lake's water level, expedite implementation of lake water diversion projects, and conduct comprehensive assessment on their potential impact on local ecological environment.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107663"},"PeriodicalIF":3.4,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164548","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Appraising the porphyry Cu fertility using apatite trace elements: A machine learning method","authors":"Qianbin Liang ,&nbsp;Guoxiong Chen ,&nbsp;Lei Luo ,&nbsp;Xiaowen Huang ,&nbsp;Hao Hu","doi":"10.1016/j.gexplo.2024.107664","DOIUrl":"10.1016/j.gexplo.2024.107664","url":null,"abstract":"<div><div>Apatite chemical composition has often been invoked for appraising the magmatic copper (Cu) fertility, because trace elements in apatite hold important clues for tracing magma composition, oxidation states, and crystallization processes. However, low-dimensional Cu fertility discriminants developed on apatite trace elements suffer from significant limitations and uncertainties in practice. Here, machine learning (ML) models including random forests and support vector machines were trained using high-dimensional apatite composition dataset (spanning 20 trace elements) for discriminating ore-bearing magmas from ore-barren magmas. The results suggest that the ML models obtained a higher accuracy (96 %) for identifying the given apatites from ore-bearing samples compared to that of traditional discriminant diagrams (56 %). The feature importance analysis suggests that <em>δ</em>Eu and Sr are the most significant proxy for distinguishing ore-bearing and ore-barren samples when using high-dimensional ML models. In general, apatites from ore-bearing intrusion have higher <em>δ</em>Eu and Sr concentration, lower Pb concentration, and elevated Sr/Y ratio than ore-barren samples. Specifically, the elevated <em>δ</em>Eu and Sr concentration indicate a relatively higher oxidation state and water content in parental magmas, which could have promoted sulfate formation and Cu release and transport. Moreover, the elevated Sr/Y observed in apatite from ore-bearing samples imply the adakite-like composition of the ore-productive magmas, while lower Pb concentration suggests strong fluid participation during magmas evolution. The trained ML model was applied to apatites from the Tampakan district of the Philippines, providing new insights on Cu fertility of pre-, syn- and post-ore intrusions. The general applicability of this model demonstrates that ML-based discriminants developed on mineral trace element data provide new powerful tools for appraising the porphyry Cu fertility.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107664"},"PeriodicalIF":3.4,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164549","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neoproterozoic WSn mineralization in the western Jiangnan Orogen, South China: Insights from the Fanjingshan S-type granites","authors":"Jin-Cheng Luo ,&nbsp;Jiawei Zhang ,&nbsp;Xujie Shu ,&nbsp;Yanwen Tang ,&nbsp;Yaran Dai ,&nbsp;Weipeng Liu ,&nbsp;Xiaocui Chen ,&nbsp;Tingting Zhang","doi":"10.1016/j.gexplo.2024.107660","DOIUrl":"10.1016/j.gexplo.2024.107660","url":null,"abstract":"<div><div>The Jiangnan Orogen boasts abundant Neoproterozoic granitoids alongside locally significant W<img>Sn mineralization in South China. However, the factors governing the relationships between granites and the W<img>Sn mineralization remain elusive. Notably, Neoproterozoic W<img>Sn mineralization locally occurred within the western margin of the Jiangnan Orogen, encompassing important deposits like the Jiumao and Baotan deposits. The W-Sn-bearing tourmaline muscovite (Taoshulin) granite intruded into Neoproterozoic Fanjingshan Group, comprising low-degree metamorphosed sedimentary rocks that locally contain granitic gravel (two-mica granite). These granites in this study have high SiO₂ (73.6–77.4 wt%), Al₂O₃ (12.8–15.1 wt%), Na₂O (3.16–5.25 wt%) and high A/CNK values (1.28–1.47), which display co-variation trends. They have extremely low rare earth element (REE) concentrations (&lt; 35 ppm) and exhibit REE patterns characterized by strong negative Eu anomalies (&lt; 0.28), implying highly fractional crystallization. Zircon and apatite LA-ICP-MS U<img>Pb dating reveal that the emplacement of the Taoshulin tourmaline muscovite granite occurred <em>ca.</em> 830 Ma, similar to the U<img>Pb age (835 ± 7 Ma) of cassiterite, establishing the clear temporal-genetic relationship between granites and W<img>Sn mineralization. The zircon U<img>Pb age of 849 ± 9 Ma and the apatite U<img>Pb age of 852 ± 7 Ma obtained from the two-mica granite likely indicate <em>ca.</em> 850 Ma granitic magmatism event. These two-episode granites exhibit negative ε_Hf(t) values (+0.9 to −8.0), corresponding to two-stage Hf model ages of 1.7 to 2.2 Ga, indicating their derivation from Paleoproterozoic metasedimentary basement rocks. It is noteworthy that the W-Sn-bearing granite has high tetrad effect (TE_1,3 = 1.16–1.24) and very low Nb/Ta ratios (mostly ≤ 4) that may have resulted from magmatic-hydrothermal alteration. Moreover, the <em>ca.</em> 830 Ma W-Sn-bearing granite is characterized by a notable concentration of high F, distinctively negative Eu anomalies, and non-chondritic REE behavior in apatite. Hence, the W<img>Sn mineralization in the Fanjingshan region was probably constrained by various factors, including source materials, magmatic processes and magmatic-hydrothermal processes. Our findings highlight the pivotal role played by Neoproterozoic muscovite tourmaline granites as host for W<img>Sn mineralization in the Fanjingshan region. In summary, this study emphasizes the significance of the <em>ca.</em> 830 Ma highly differentiated S-type granites holding significant potential for the exploration of critical metals such as W, Sn, Nb, and Ta in the western part of the Jiangnan Orogen and in geologically analogous regions across the globe.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107660"},"PeriodicalIF":3.4,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164547","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatial distributions, potential sources, and ecological risks of heavy metals in stream sediments in Zambia","authors":"Hongwei Sun ,&nbsp;Junping Ren ,&nbsp;Jie Wang ,&nbsp;Jianzhong Yu ,&nbsp;Libo Zuo ,&nbsp;Xingyuan Wu ,&nbsp;Chipilauka Mukofu ,&nbsp;Alphet Phaskani Dokowe ,&nbsp;Shuping Cao ,&nbsp;Xujiang Cheng","doi":"10.1016/j.gexplo.2024.107659","DOIUrl":"10.1016/j.gexplo.2024.107659","url":null,"abstract":"<div><div>The ecological risk assessment and source identification of heavy metals (HMs) are significant for resource utilization and food security. This study aims to assess the spatial distributions, potential sources, and ecological risks of HMs in stream sediments in Zambia. Using 735 samples collected from stream sediments across the country and methods such as inductively coupled plasma mass spectrometry (ICP-MS), atomic fluorescence spectrometry (AFS), and X-ray fluorescence spectrometry (XRFS), this study determined the concentrations of the seven HMs, i.e., arsenic (As), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb), and zinc (Zn). The spatial distributions of these HMs were determined using a Geographic Information System (GIS), and their ecological risks were accessed based on the analytical results of their potential sources. Additionally, this study explored the relationships between mining activities and regions with high heavy metal (HM) concentrations based on the statistical analysis of the HM concentrations and geology of the study area. The results indicate the stream sediments in Zambia exhibit average As, Cr, Cu, Hg, Ni, Pb, and Zn concentrations of 1.49 × 10⁻⁶, 19.34 × 10⁻⁶, 12.12 × 10⁻⁶, 12.70 × 10⁻⁹, 7.13 × 10⁻⁶, 12.52 × 10⁻⁶, and 16.30 × 10⁻⁶, respectively. The analytical results of the geoaccumulation index (<em>I</em>_geo) and potential ecological risk index (PERI) reveal the presence of relatively high As and Cu concentrations, especially in Copperbelt and North-Western provinces and areas surrounding Lusaka—the capital of Zambia. The HM contamination in stream sediments in Zambia is primarily caused by Cu and gold (Au) mining. This study exemplifies how to determine potential sources and ecological risks of HMs in stream sediments, holding important implications for nation-scale environmental contamination prevention and land utilization planning.</div></div>","PeriodicalId":16336,"journal":{"name":"Journal of Geochemical Exploration","volume":"270 ","pages":"Article 107659"},"PeriodicalIF":3.4,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143164046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}