Soil & Environmental Health最新文献

{"title":"Dominance of 2:1 clay minerals in soil potassium across a weathering gradient: Insights from XANES speciation and sequential extraction","authors":"Worachart Wisawapipat ,&nbsp;Apinya Saentho ,&nbsp;Itsada Bunthong ,&nbsp;Piyapas Sricharoenvech ,&nbsp;Sompin Mahakot ,&nbsp;Wantana Klysubun","doi":"10.1016/j.seh.2026.100194","DOIUrl":"10.1016/j.seh.2026.100194","url":null,"abstract":"<div><div>Potassium (K) is essential in the soil–plant–human continuum, yet its chemical speciation in soils with different weathering stages and in their clay fractions remains poorly understood. Herein, we investigated K speciation and fractionation in 15 tropical soils (Luvisols, Acrisols, and Ferralsols) and 8 clay fractions. Potassium <em>K-</em>edge X-ray absorption near edge structure (XANES) spectra of soils and clays revealed the dominance of 2:1 clay minerals at 70%, particularly beidellite, illite–smectite, montmorillonite, and illite. Kaolinite was minor at 10%, whereas primary silicates remained detectable at 18%. Potassium associated with organic matter contributed to only a small fraction at 2%. Less-weathered soils contained beidellite together with illite, illite–smectite, and montmorillonite, whereas highly weathered soils had kaolinite and montmorillonite. However, illite–smectite and montmorillonite cannot unequivocally be distinguished by XANES spectroscopy. This spectroscopic evidence indicates that the XANES underlines the primary contribution of 2:1 phyllosilicates as the host phase for K in the soils, particularly in less weathered soils. Operationally-defined sequential extraction of soils further revealed little water-soluble and exchangeable fractions, with no trend between the soils across different weathering stages. Nonetheless, clay-rich soils possessed a larger fraction of exchangeable K, while sandy soils contained little. Considering relative fractions, however, sandy soils exhibited higher values of water-soluble and exchangeable pools, though these corresponded to small fraction. This finding highlights the importance of assessing both absolute and relative K pools when evaluating soil health. Our results highlight the dominance of 2:1 clay minerals as primary K sources and sinks in soils across a weathering sequence in tropics, while primary silicates also contribute to long-term K cycling. Combining spectroscopic and sequential extraction provides insights into K speciation and fractionation in soils that can be used to assess soil health and sustain K availability in soil systems.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 2","pages":"Article 100194"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146174680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aging of polyethylene microplastics in agricultural soils has minimal effect on sorption and desorption of wastewater-derived organic contaminants","authors":"Yuval Shahar ,&nbsp;Raz Lev ,&nbsp;Vered Mordehay ,&nbsp;Evyatar Ben Mordechay ,&nbsp;Benny Chefetz","doi":"10.1016/j.seh.2026.100207","DOIUrl":"10.1016/j.seh.2026.100207","url":null,"abstract":"<div><div>Microplastics in agricultural soils may act as sorptive agents for organic contaminants. This study investigated the effects of soil aging of linear low-density polyethylene (LLDPE) microplastics on the sorption and desorption of wastewater-derived organic contaminants. LLDPE microparticles 1% (700-1000 μm) were aged in three arable Entisols, with soil sampling being conducted after 0, 6, 11, 15, and 20 months of aging. At each sampling time, microparticles were extracted, characterized, and used as sorbents for 48 organic contaminants. Soil aging resulted in pronounced modifications of the LLDPE surface, mostly during the early stages of aging. These changes included an increase in polar surface characteristics, primarily due to the formation of an organic surface coating. Despite these changes, for most tested contaminants, the change in sorption affinity with aging time was limited. Only six contaminants exhibited an increased sorption affinity exceeding one order of magnitude, primarily during the first 11 months of aging. Desorption experiments further indicated that, for most contaminants, sorption was reversible and independent of soil aging. Our data show that the soil organic matter or clay contents had little effect on the aging of LLDPE microplastics, in terms of both surface properties and organic contaminant sorption affinities. From an environmental perspective, these results quantitatively confirm that the contribution of LLDPE microplastics to the overall sorption affinity of the receiving soils is limited, mainly due to their low specific surface area and relatively low abundance in soils. Accordingly, the presence of LLDPE microplastics in agricultural soils influences contaminant behavior primarily at the local, microscale level rather than altering the overall sorption dynamics of the soil.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 2","pages":"Article 100207"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147703060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupling methane oxidation to pollutant transformation: a microbiome framework for climate mitigation and soil remediation","authors":"Kang-Hua Chen ,&nbsp;Jiao Feng ,&nbsp;Qiaoyun Huang ,&nbsp;Xianjin Tang ,&nbsp;Hanzhong Jia ,&nbsp;Yu-Rong Liu","doi":"10.1016/j.seh.2026.100202","DOIUrl":"10.1016/j.seh.2026.100202","url":null,"abstract":"<div><div>Methane emissions and chemical pollutants often co-occur in natural and engineered environments, contributing to ecosystem degradation. Microorganisms play key roles in regulating these processes through methane oxidation and pollutant transformation, thereby linking greenhouse gas dynamics with contaminant fate and risk across soils and aquatic systems. In this review, we summarize current knowledge on microbial species (methanotrophs) involved in methane oxidation and the transformation of metal(loid)s (As, Cr, V, Sb and Hg) and organic pollutants (trichloroethylene, sulfamethoxazole, and PAHs), with a focus on both aerobic and anaerobic pathways in environmental and engineered systems. We examine how methane oxidation is coupled to pollutant transformation through direct enzymatic reactions carried out by methanotrophs, as well as through indirect pathways involving electron transfer and intermediates released from methane oxidation. Depending on pollutant types and redox conditions, these couplings can result in contrasting outcomes, with different toxicity and mobility. Building upon this understanding, we propose a conceptual framework to guide microbiome-based strategies for concurrent mitigation of methane emissions and risks from metal and organic pollutants in soils and aquatic systems. The framework integrates site-specific characterization of pollutant profiles and microbial communities, including aerobic and anaerobic methanotrophs and associated pollutant-transforming microorganisms, with targeted manipulation of microbial consortia through top-down and bottom-up approaches, together with monitoring of key biogeochemical indicators to support context-dependent decision-making. By linking process-level coupling mechanisms with decision-oriented microbiome strategies, this framework provides a structured basis for evaluating when and how methane-related microbial processes can be harnessed for concurrent climate mitigation and soil remediation under site-specific redox and contamination conditions.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 2","pages":"Article 100202"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146174679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rapid and accurate phytate quantification in plant tissues and grains via ion chromatography: Validation and application","authors":"Chunyan Hu ,&nbsp;Chenjing Liu ,&nbsp;Shufen Xiao ,&nbsp;Yuxuan Chen ,&nbsp;Ruimin Jin ,&nbsp;Chaogang Xing ,&nbsp;Yue Cao ,&nbsp;Lena Q. Ma","doi":"10.1016/j.seh.2026.100195","DOIUrl":"10.1016/j.seh.2026.100195","url":null,"abstract":"<div><div>Phytate (salts of <em>myo</em>-inositol hexakisphosphate) represents 65–90 % of total phosphorus in the grains, yet its accurate quantification in plant samples remains challenging. In this study, a novel ion chromatography method coupled with suppressed conductivity detection (IC−SCD) was developed for rapid and accurrate phytate determination in 15 plant samples. These included two model plants (<em>N. tabacum and A. thaliana</em>), four crop plants (<em>O. sativa, B. rapa, S. lycopersicum, and T. aestivum</em>), four fern plants (<em>P. ensiformis, P. vittata, P. multifida, and P. cretica</em>), and five grain samples (maize, rice, barley, oat, and wheat). The IC−SCD method achieved a low detection limit of 0.2 mg/L (0.04 mg/g) and enabled effective phytate separation from interferences of inositol trisphosphate and common organic acids, including malate, tartrate, oxalate, and citrate, which are inadequately resolved by high-performance liquid chromatography. Compared with the Wade method, which determines phytate by spectrophotometric measurement of absorbance after reaction with ferric chloride and sulfosalicylic acid, the phytate contents determined by IC−SCD were comparable in 5 grain samples (1.64−3.11 mg/g). However, much lower and more accurate values were obtained in 10 plant tissues (0.20−1.14 vs. 6.67−8.01 mg/g), with <em>P. vittata</em> showing the highest phytate content. The data indicate that Wade method overestimates phytate in plant tissues due to interference from organic acidss. This study demonstrates that the IC−SCD method provides a reliable and cost-effective analytical approach for rapid and accurate phytate determination, supporting improved evaluation of phosphorus dynamics in plant and feed research.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 2","pages":"Article 100195"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146090786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Healthy soil as the invisible determinant of a healthy environment: A critical review","authors":"Peng Gao","doi":"10.1016/j.seh.2026.100214","DOIUrl":"10.1016/j.seh.2026.100214","url":null,"abstract":"<div><div>Soil is a living, finite resource governing chemical fate, microbial ecology, nutrient supply, and climate regulation, yet environmental science and policy often treat it as an inert substrate. Approximately one-third of global soils are moderately to highly degraded, with an estimated 36 Gt of topsoil being lost to erosion annually, and erosion-related health and environmental externalities costing the US ∼$67 billion annually. Despite existing soil governance frameworks in many jurisdictions, no global system of health-linked routine soil surveillance comparable to air and water quality monitoring has been established, and these burden indicators do not quantify causal effect sizes for soil-to-health links. This review maps evidence linking soil state and management to measured exposure metrics and health endpoints. It grades evidence maturity across five pathways: food chain contamination, water quality impairment, airborne particulate exposure, direct microbial contact, and antimicrobial resistance dissemination. Soil degradation amplifies chemical, biological, and climate-related health risks spanning outcomes from micronutrient deficiencies to soil-transmitted helminthiases, with persistent pollutants in soils constituting an additional food-chain exposure burden. Evidence maturity varies markedly: food-chain, water, and air-dust pathways are well-characterized, whereas the soil–gut axis and antimicrobial resistance links remain largely inferential. Temporal lags, spatial heterogeneity, unpriced ecosystem services, and institutional fragmentation collectively perpetuate soil's invisibility in environmental health practice. Monitoring, intervention, and governance approaches are evaluated, highlighting the roles of multi-omics, remote sensing, exposomics, and regenerative land management. A provisional tiered threshold framework is proposed, comprising screening-level indicators, site-specific risk assessment, and actionable management triggers linked to health-relevant endpoints, with empirical validation remaining a research priority. Soil needs to transition from a background substrate to measurable, manageable infrastructure within an expanded One Health framework. Its governance should match the level of ambition applied to air and water protection.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 2","pages":"Article 100214"},"PeriodicalIF":0.0,"publicationDate":"2026-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147703061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Path to robust digital mapping of soil C:N ratio: geographic bias and uncertainty gap","authors":"Yujie Hong ,&nbsp;Lebing Wu ,&nbsp;Peipei Xue ,&nbsp;Bifeng Hu ,&nbsp;Zhou Shi ,&nbsp;Songchao Chen","doi":"10.1016/j.seh.2025.100187","DOIUrl":"10.1016/j.seh.2025.100187","url":null,"abstract":"<div><div>The carbon-to-nitrogen (C:N) ratio is a key indicator of soil quality, nutrient cycling, and ecosystem function. While advances in digital soil mapping offer powerful tools for spatially resolving soil properties, understanding of the spatial patterns of soil C:N ratio and their drivers and implications remains limited. In this review, we synthesized recent progress by analyzing 51 peer-reviewed articles published up to August 2025. Our analysis reveals that despite a rapid increase in publications, research on mapping soil C:N ratio remains limited compared to other soil properties and is characterized by biases. Research is geographically concentrated in China (45%), heavily focused on cropland ecosystems, and predominantly limited to topsoil (0–30 cm). Methodologically, direct modeling of soil C:N ratio (80%) and 2D spatial models (94%) are common. Despite recent methodological advances, major challenges remain, which include the lack of uncertainty analysis (reported in only 10% of studies), the geographic and vertical sampling biases, and the tendency for predictive models to underestimate the true range of soil C:N ratio. Future perspectives should prioritize the adoption of 3D modeling frameworks, the integration of mechanistic understanding with empirical data-driven approaches through novel environmental covariates, and the standardization of reporting for sampling and validation protocols. Future efforts should focus on broadening the geographic and contextual scope of soil C:N mapping, mandating uncertainty quantification, and enhancing methodological transparency to produce more robust and globally relevant soil information.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 1","pages":"Article 100187"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145940429","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Earthworms and phytate drive phosphorus hotspots in the drilosphere: Enzymatic, microbial, and spatial insights from in situ imaging","authors":"Zhen-Yu Qiang ,&nbsp;Dong-Xing Guan ,&nbsp;Jia-Lu Gao ,&nbsp;Kai Ding ,&nbsp;Gang Li ,&nbsp;Nader Saad Elsayed ,&nbsp;Lena Q. Ma","doi":"10.1016/j.seh.2025.100186","DOIUrl":"10.1016/j.seh.2025.100186","url":null,"abstract":"<div><div>Soil organic phosphorus (P) represents a critical component of terrestrial ecosystems, yet its mineralization dynamics in biologically-active zones like earthworm drilosphere remain poorly understood. This study combined microcosm experiments with <em>in situ</em> imaging to elucidate the mechanisms of phytate mineralization in earthworm drilosphere, 2-mm soil layer surrounding the burrows. Under phytate application, endogeic earthworms increased the available P content by 6.3 % in the drilosphere and elevated phytase activity by 38%. <em>In situ</em> imaging using diffusive gradients in thin-films and soil zymography revealed that phytate application increased the maximum labile P flux by 54% and maximum acid phosphatase activity by 67%. Hotspot analysis showed phytate application expanded labile P hotspots from 3.1 to 4.2% in soil while reducing acid phosphatase hotspots from 4.8 to 4.6%, indicating elevated baseline enzyme activity in the drilosphere. Microbial community analysis revealed that earthworms restructured drilosphere communities, with <em>Gammaproteobacteria</em> and <em>Sordariomycetes</em> emerging as dominant functional taxa. Functional gene expression analysis showed selective upregulation of phytase genes <em>phoD</em> and <em>phyA</em> and downregulation of P-starvation response genes <em>phoU</em> and <em>phoR</em>, boosting microbial P acquisition capacity. These findings demonstrate that earthworms drive phytate mineralization through integrated mechanisms: enzymatic effects, gene regulations, and microbial community restructure. This work helps to understand the spatially-heterogeneous P dynamics, highlighting soil fauna as ecosystem engineers by creating self-reinforcing systems to maximize organic P utilization.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 1","pages":"Article 100186"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145886074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Carbonate Bedrock Shapes Soil Health: metal enrichment, nutrient limitation, and carbon sequestration in karst soil","authors":"Guobing Lin,&nbsp;Chenjing Liu,&nbsp;Yuanchen Zhang,&nbsp;Lena Q. Ma","doi":"10.1016/j.seh.2025.100189","DOIUrl":"10.1016/j.seh.2025.100189","url":null,"abstract":"<div><div>Southwest China hosts the world's largest karst landscape, with karst soil derived from carbonate bedrock being widespread. Meanwhile, non-karst soil developed from silicate-rich clastic rocks is intermixed in this region. Unlike clastic rocks, carbonate rocks have unique lithological characteristics including abundant easily-soluble CaCO₃ and MgCO₃, and high weathering rates, which may shape different soil properties. Based on 1053 observations from 87 articles, we compared soil health between karst and non-karst soil to study the impacts of bedrock lithology, with heavy metals and nutrient elements being the main indicators. Our meta-analyses indicate that, compared to non-karst soil, karst soil had 433% higher Ca contents and 37−117% greater Fe/Mn contents on average. The abundant CaCO₃ contributed to 25−28% higher pH and macroaggregate in karst soil. The secondary enrichment by Fe/Mn oxides likely contributes to 110–398% greater Cd, As, Cr, Pb, and Hg contents in karst soil, with limited phytoavailability. Additionally, the abundant CaCO₃, Fe/Mn minerals, and macroaggregates provided critical physical barriers to protect organic matters from decomposing, resulting in 41–70% increase in total C, N and P, accompanied by 87–149% higher microbial C, N and P, but 27–36% lower DOC, NH₄⁺-N, and available P in karst soil. Collectively, the higher enrichment of toxic metals and lower nutrient availability potentially pose negative impacts on plant growth, while the greater C sequestration, aggregate stability, and microbial diversity may have positive effects on karst soil health. Our work revealed the linkage of bedrock lithology to soil health in karst and non-karst soil and assessed the characteristics of karst soil from multiple perspectives. This review helps to better understand karst soil health and provides critical insights for their sustainable development.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 1","pages":"Article 100189"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145886129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Urban garden soils and vegetables as vectors of potentially toxic elements across Bratislava: Citywide distribution, sources, and health implications","authors":"Edgar Hiller ,&nbsp;Zuzana Škerliková Pilková ,&nbsp;Lenka Filová ,&nbsp;Martin Mihaljevič ,&nbsp;Tomáš Faragó ,&nbsp;Martina Vítková ,&nbsp;Ľubomír Jurkovič","doi":"10.1016/j.seh.2026.100192","DOIUrl":"10.1016/j.seh.2026.100192","url":null,"abstract":"<div><div>Urban gardening offers multiple societal benefits, supporting both mental and physical well-being while enhancing access to fresh, locally grown produce. However, it may also pose potential health risks due to contamination of urban soils with potentially toxic elements (PTEs), including metal(loid)s. This study investigated metal(loid) concentrations in soils and homegrown vegetables from urban gardens across Bratislava (Slovak Republic) and evaluated the factors affecting their accumulation and bioavailability. Median Cu concentration in vineyard soils (51 mg kg^-1) was twice those in non-vineyard soils (25 mg kg^-1). In contrast, raised-beds gardens exhibited significantly lower concentrations of most metal(loid)s compared to ground plots (<em>p</em>&lt;0.05). Soil concentrations of Cd, Cu, Pb, Sb, and Zn showed a positive correlation with garden age and negative correlation with distance from the historical city core (pre-1946 boundary), suggesting legacy anthropogenic inputs. Integrated analyses, including enrichment factor calculations and statistical source apportionment, confirmed that Cd, Cu, Pb, Sb, and Zn in garden soils originated predominantly from anthropogenic sources; whereas, metal(loid)s such as Al, Cr, Li, Ni, and V were likely governed by natural geological processes, including variation in parent material composition. Concentrations of Cd, Ni, and Pb in edible vegetables remained below the maximum allowable limits set by EU regulations. Estimated daily intakes of all metal(loid)s, based on average vegetable consumption, were substantially below respective tolerable daily intake thresholds. Human health assessments indicated negligible non-carcinogenic risks (hazard index <em>&lt;</em> 1.0) and low carcinogenic risk (<em>&lt;</em> 10^–4), suggesting minimal public health concerns associated with consumption of homegrown produce or incidental soil exposure in these gardens. This study represents a comprehensive, citywide assessment of metal(loid) distribution in urban gardens within a medium-sized Central European city. It advances scientific understanding of metal(loid) dynamics in urban agroecosystems and supports evidence-based guidance to enhance public awareness of both the benefits and potential risks of urban agriculture.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 1","pages":"Article 100192"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979439","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Coupling positive matrix factorization with machine learning to quantify contamination sources and map health risks of heavy metals in karst soils","authors":"Zhenhai Liu ,&nbsp;Yang Zeng ,&nbsp;Wanzhou Wang ,&nbsp;Bolun Zhang ,&nbsp;Jiameng Liu ,&nbsp;Xiaoli Zhao","doi":"10.1016/j.seh.2026.100193","DOIUrl":"10.1016/j.seh.2026.100193","url":null,"abstract":"<div><div>Heavy metal contamination in karst ecosystems poses great environmental risks due to the interplay between high geochemical backgrounds and anthropogenic activities. This study performed an integrated source-to-risk assessment of soil metals based on 674 topsoil samples from Guangxi karst region in China, combining three machine learning models including positive matrix factorization (PMF), random forest (RF), and multiscale geographically weighted regression (MGWR). Geochemical characterization identified SiO₂ (63%), Al₂O₃ (18%), and Fe₂O₃ (6.4%) as dominant oxides in tested soils, with higher organic matter (3.3% content) than regional background value. A majority of 36 examined metals displayed concentrations exceeding local background values, of which Cd and Hg exhibited the highest enrichment levels (3.83 and 6.75 folds of background values, respectively). PMF revealed distinct source patterns across land-use types, with natural weathering dominating in forest land, and agricultural inputs prevailing in grasslands. Riparian land was primarily influenced by traffic-related anthropogenic activities, while construction land was dominated by industrial and mining/smelting sources. PMF-RF-MGWR modeling demonstrated pronounced spatial heterogeneity with contamination hotspots being mainly concentrated in industrial- and mining-intensive areas of central-western Guangxi. Notably, karst weathering increased soil metal mobility, while secondary carbonate mineral formation contributed to immobilization of Cd and Pb. Health risk assessment identified As, Cr and Ni as priority contaminants, and their presence in industrial zones posed unacceptable carcinogenic risks. Our findings underscore the role of the interplay between geological processes and anthropogenic activities in shaping metal distribution, providing valuable references for targeted soil management and contaminated land remediation in karst regions.</div></div>","PeriodicalId":94356,"journal":{"name":"Soil & Environmental Health","volume":"4 1","pages":"Article 100193"},"PeriodicalIF":0.0,"publicationDate":"2026-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145979438","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}