Journal of contaminant hydrology最新文献

{"title":"Fate, chlorination kinetics, and comprehensive risk assessment of pharmaceuticals and personal care products in drinking water distribution systems","authors":"Zhenglin Li ,&nbsp;Nan Li ,&nbsp;Fei Wang ,&nbsp;Minru Xiao ,&nbsp;Anlei Wei","doi":"10.1016/j.jconhyd.2026.104842","DOIUrl":"10.1016/j.jconhyd.2026.104842","url":null,"abstract":"<div><div>The widespread occurrence of pharmaceuticals and personal care products (PPCPs) in aquatic environments has emerged as a global concern due to their potential threats to water security and ecological health. Despite increasing attention, their fate and associated risks in drinking water systems remain insufficiently understood. The occurrence, transformation behavior, and ecological and human health risks of 19 PPCPs were investigated across drinking water treatment and distribution systems in this study. Eighteen PPCPs were ubiquitously detected in raw water, with high detection frequencies (&gt;70 %), whereas both the number of detected compounds and their concentrations were markedly reduced in finished water (five compounds) and tap water (eleven compounds). These results demonstrate the substantial effectiveness of conventional treatment processes in reducing both the diversity and concentrations of PPCPs. To further elucidate their potential transformation during water treatment, chlorination kinetics of eight structurally diverse PPCPs were evaluated under controlled conditions. Four compounds (atenolol, sulpiride, paroxetine, and nadolol) exhibited pseudo-first-order kinetics with residual chlorine, while the others exhibited significant resistance to chlorination. Degradation efficiency was found to depend on both the water matrix conditions and their molecular properties, highlighting the combined roles of intrinsic chemical properties and environmental complexity. Ecological risk assessment revealed ibuprofen posed a moderate ecological risk, a risk quotient (RQ) of 0.335, while triclocarban presented a high ecological risk (RQ = 4.6031). Mixture toxicity assessment based on the cumulative toxic unit (ΣTU) further indicated a potential ecological risk (ΣTU &gt; 1) in raw water. Human health risk assessment showed minimal risks across all age groups (RQ 〈10⁻³). However, infants were identified as the most susceptible population, likely due to their higher exposure relative to body weight. Among the detected PPCPs, meclofenamic acid was identified as the compound of highest concern, with average relative risk indices exceeding &gt;10⁻⁴. These findings provide critical insights into the fate and transformation of PPCPs in drinking water systems and offer scientific guidance for optimizing treatment processes and risk management strategies.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104842"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145921313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Intensive anthropogenic activities drive dynamic surface water-groundwater interactions: Implications for contaminant pathways at a catchment scale","authors":"Shunqing Jia ,&nbsp;Xihua Wang ,&nbsp;Y. Jun Xu ,&nbsp;Chaomeng Dai ,&nbsp;Nianqing Zhou ,&nbsp;Zejun Liu ,&nbsp;Boyang Mao ,&nbsp;Qinya Lv ,&nbsp;Xuming Ji ,&nbsp;Chengming Luo ,&nbsp;Yan Dai ,&nbsp;Yanxin Rong","doi":"10.1016/j.jconhyd.2025.104808","DOIUrl":"10.1016/j.jconhyd.2025.104808","url":null,"abstract":"<div><div>Interactions between surface water and groundwater (SW-GW) are critical interfaces controlling contaminant fate and transport. However, their dynamic behavior at the catchment scale under intensive anthropogenic stress remains poorly understood. This study integrates hydrogeochemical and isotopic analyses (δ¹⁸O, δ²H) to investigate the spatiotemporal patterns of SW-GW interactions and their implications for contaminant pathways in the Yiluo River Watershed, a major agricultural region in China. Three sampling campaigns were conducted across low-flow (Nov 2022, T1), normal-flow (May 2023, T2), and high-flow (Aug 2023, T3) periods. Results show that while waters are predominantly Ca–HCO₃ type, geochemical and isotopic signatures reveal highly dynamic exchange processes. Isotopic enrichment from upstream to downstream (δ¹⁸O from ∼ − 10 ‰ to ∼ − 6.5 ‰) indicates significant evaporation and mixing. Crucially, SW-GW interactions create fluctuating pathways for contaminants like nitrate (NO₃⁻). During the T1 dry/irrigation season, extensive groundwater abstraction for agriculture reverses local hydraulic gradients, reducing river-to-groundwater recharge and inducing high-nitrate groundwater discharge into the river, with groundwater NO₃⁻ concentrations reaching up to 42.5 mg/L. Correlation analysis reveals that the dominant controls on recharge ratios shift seasonally: from cropland (<em>r</em> = −0.53) and forest (<em>r</em> = 0.49) in the dry season to population density (<em>r</em> = −0.26) and bare land (<em>r</em> = 0.35) in the wet season. These findings reveal a conceptual framework where seasonal human activities (e.g., irrigation vs. urban runoff) actively switch the direction and magnitude of contaminant exchange pathways between surface and subsurface systems. This study highlights the necessity of integrated, dynamic management of SW-GW resources to mitigate contamination risks in anthropogenically-dominated agricultural catchments worldwide.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104808"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparative analysis of column experiments highlights the suitability and challenges of using common plant-based viruses as surrogates for human adenovirus in saturated porous media","authors":"Emmanuel Cobbinah ,&nbsp;Subhash C. Verma ,&nbsp;Krishna Pagilla ,&nbsp;Rishi Parashar","doi":"10.1016/j.jconhyd.2025.104831","DOIUrl":"10.1016/j.jconhyd.2025.104831","url":null,"abstract":"<div><div>Understanding virus transport in porous media is crucial for assessing the risks associated with viral contamination in subsurface environments. Plant and human viruses may enter water systems through agricultural runoff, wastewater discharge, or other pathways, necessitating a detailed investigation of their mobility and persistence. This study investigates the transport behavior of Tomato Brown Rugose Fruit Virus (ToBRFV), Pepper Mild Mottle Virus (PMMoV), and human adenovirus (HAdV) in porous media using controlled laboratory column experiments packed with uniform size glass beads. Breakthrough curves generated were analyzed using an advection-dispersion-reaction equation to model each virus's transport dynamics. The two plant-based viruses, ToBRFV and PMMoV, exhibited similar transport profiles with sharp breakthrough onsets and pronounced tailing, whereas HAdV showed a more gradual breakthrough, indicating distinct transport dynamics. The differences in transport were largely attributed to the morphological differences between plant viruses and human adenovirus. Additionally, variations in influent water chemistry, particularly pH, appear to significantly influence virus transport by modifying the DLVO interaction energy between viral particles and glass bead surfaces. While no direct one-to-one correlation was observed between the transport of HAdV and the plant viruses, statistical analysis revealed ToBRFV as a more reliable surrogate compared to PMMoV. By elucidating key factors influencing viral transport, this study provides insights that could inform risk assessments and mitigation strategies for waterborne viral contamination. These findings highlight the potential role of viral morphology and water chemistry in identifying reliable viral surrogates for subsurface transport assessments.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104831"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837533","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aggregation kinetics and stability of Ce(IV)-borate colloid: Effect of pH, electrolytes, gibbsite colloid, and humic acid colloid","authors":"Kang Chen ,&nbsp;Rui Zhang ,&nbsp;Chunsheng Shi ,&nbsp;Shanrong Yuan ,&nbsp;Zishuo Li ,&nbsp;Daming Zhang ,&nbsp;Qiang Jin ,&nbsp;Zhijun Guo ,&nbsp;Zongyuan Chen","doi":"10.1016/j.jconhyd.2025.104811","DOIUrl":"10.1016/j.jconhyd.2025.104811","url":null,"abstract":"<div><div>Tetravalent actinides (An(IV)), could be released from high-level radioactive waste (HLW) glass in the form of An(IV)-borate intrinsic colloid. In this study, Ce(IV) was selected as the analogue of An(IV), and the stability of Ce(IV)-borate colloid was studied as a function of pH, electrolytes, gibbsite colloid, and humic acid (HA) colloid by aggregation kinetics experiments. The isoelectric point (pH_IEP) of Ce(IV)-borate colloid was determined to be 7.8, and aggregation of the colloid was increased progressively with the pH approaching this value. The critical coagulation concentrations (CCC) were followed the order that NaCl &gt; KCl &gt; MgCl₂ &gt; NaNO₃ &gt; CaCl₂ &gt; Na₂SO₄. The positively charged gibbsite colloid inhibited the aggregation of Ce(IV)-borate colloid due to enhanced electrostatic repulsion. In contrast, the effect of negatively charged HA on the stability of Ce(IV)-borate colloid was dependent on HA concentration. The presence of low concentrations of HA (0.1–1.0 mg/L) reduced the surface charge of Ce(IV)-borate colloids, resulting in lower CCC, whereas the higher HA concentrations (2.5–25 mg/L) enhanced the colloidal stability of Ce(IV)-borate particles. The Hamaker constant of Ce(IV)-borate colloid was calculated to be 1.29 × 10⁻²⁰ J. The interaction energy calculated with Derjaguin–Landau–Verwey–Overbeek (DLVO) theory and its variants can well describe the changes of colloidal stability. These results provide comprehensive understanding of Ce(IV)-borate colloid properties and offer valuable insights for assessing the fate and transport of An(IV) in real subsurface environments.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104811"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788161","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unraveling the adsorption mechanisms of greenhouse gases on microporous MAF-4 nanoparticles using a statistical physics approach","authors":"E.A. Elghmaz ,&nbsp;Ghada M. Alnafesah ,&nbsp;Mohammed Alissa ,&nbsp;Khalil ur Rehman ,&nbsp;Abdullah Alghamdi ,&nbsp;Suad A. Alghamdi ,&nbsp;Abdulkarim S. Binshaya ,&nbsp;Ghfren S. Aloraini ,&nbsp;Amira K. Hajri ,&nbsp;Adil Abalkhail","doi":"10.1016/j.jconhyd.2026.104850","DOIUrl":"10.1016/j.jconhyd.2026.104850","url":null,"abstract":"<div><div>The continuing struggle to reduce greenhouse gas emissions continues to be one of the most crucial obstacles in achieving both energy efficiency and sustainable, long-term environmental practices. Microporous metal azolate framework-4 nanoparticles (MAF-4 NPs) have emerged as attractive adsorbent materials with their large surface area, adjustable pore architecture, and high chemical stability. Herein we present a green and rapid synthesis of ultramicroporous MAF-4 nanoparticles via the production of no organic solvents through the use of minimal external heating. The resulting MAF-4 NPs (particle size ≥70 nm) have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and nitrogen physisorption analysis and demonstrate a high BET surface area of 1796 m³/g, a total pore volume of 0.75 cm³/g, and ultramicropores predominantly occurring at an average pore diameter of 0.62 nm. A number of gas adsorption behaviors have been experimentally evaluated for four different gases (CO₂, SF₆, CH₄, and N₂) and are subsequently explained using a multilayer adsorption model based on statistical physics that has recently been developed for porous metal-organic frameworks. This combination of theoretical and experimental information provides a greater understanding of how adsorption occurs within porous metal-organic frameworks. The results indicate that gas molecules (at low temperatures) are unaligned, but at higher temperatures they have primarily parallel arrangements and are able to form many layers (multilayer arrangements). The average number of adsorbed gas molecules on an active site range from 0.51 to 1.92 for each different type of gas and temperature combination, and the total number of layers varies from 1.2 to 8.0. Energy of adsorption indicates strong attractive forces for the initial layer of adsorbing molecules and a decrease in attraction for subsequent layers of adsorbing molecules, with values between 2.64 and 8.42 kJ/mol indicating the adsorptive forces are due to physisorption with significant contributions from van der Waals and London dispersion forces. Using thermodynamic evaluations of internal energy and Gibbs' free energy to estimate the spontaneity and exothermicity of the adsorption process shows that at low temperatures there is more disorder among the molecules (higher entropy) than at higher temperatures when the number of adsorbate molecules reaches saturation. This indicates that MAF-4 nanoparticles will be energy-efficient, selective, and regenerable when used for CO₂ and SF₆ capture and have significant capability for scale-up and increased capacity of these adsorbates.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104850"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146010544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessment of groundwater vulnerability to heavy metals in four aquifers using machine learning algorithms","authors":"Gholamheidari Hamideh ,&nbsp;Entezari Mojgan","doi":"10.1016/j.jconhyd.2026.104853","DOIUrl":"10.1016/j.jconhyd.2026.104853","url":null,"abstract":"<div><div>Using a machine learning framework, this study investigates the spatial distribution and key environmental factors of heavy metal contamination (iron, nickel, lead, copper) in four groundwater aquifers of Isfahan province during the water year 2023–2024. A total of 150 wells were sampled and metal concentrations were determined using ICP-MS, AAS, VGA, and Mercury Analyzer methods in accordance with WHO and Iranian standards. The maximum observed concentrations of iron, nickel, lead and copper were approximately 48, 44.1, 2.9 and 11.2 mg/L respectively, with the peak concentrations of iron and copper in the Damaneh - Daran aquifers, nickel in Bouin and lead in Chadegan. Random Forest (RF) and Support Vector Machine (SVM) models were used, and in RF, 100 trees were used for accurate predictions. Multiple collinearity between environmental predictors, including soil properties, unsaturated and saturated zones, hydraulic parameters, slope, groundwater level, and aquifer depth was assessed through variance inflation factor (VIF), all of which were below 10. Model interpretation showed that soil properties and groundwater level had the greatest influence in RF, while the unsaturated layer was dominant in SVM. Iron decreased with increasing aquifer depth, pore thickness, and water table, while soil permeability and slope increased iron accumulation. Nickel was higher in shallow, shallow, and low-conductivity areas, while lead increased with depth and slope, indicating a nonlinear dependence on hydraulic and soil properties. Copper was positively correlated with soil permeability and negatively correlated with water table. Spatial predictions showed that the Bouin aquifer showed the highest iron and nickel (more than 40 and more than 30 mg/L), lead reached about 44 mg/L in Chadegan, and copper peaked in Bouin from southeast to northwest. RF outperformed SVM by achieving an accuracy of 0.7874, sensitivity of 0.7448, and specificity of 0.8243, while SVM performed poorly. This study innovatively combines machine learning models with the parameters of the DRASTIC analytical model to assess and predict heavy metal contamination in the aquifers of Isfahan province. Overall, the results confirm the nonlinear hydrogeological controls on heavy metal distribution and demonstrate the high capability of RF for reliable prediction of groundwater contamination. This approach provides a transferable method for groundwater quality assessment and supports sustainable aquifer management in arid and semi-arid regions.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104853"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146119118","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ XANES study of PFAS impacted soils filled with aqueous and non-aqueous phases","authors":"Anand Kumar ,&nbsp;Md Khairul Alam ,&nbsp;Bin Qian ,&nbsp;Mike J. Donn ,&nbsp;Divina A. Navarro ,&nbsp;John L. Rayner ,&nbsp;Greg B. Davis ,&nbsp;Bruce Cowie ,&nbsp;Bobby Pejcic ,&nbsp;Steve Fisher","doi":"10.1016/j.jconhyd.2025.104820","DOIUrl":"10.1016/j.jconhyd.2025.104820","url":null,"abstract":"<div><div><em>Per</em>- and polyfluoroalkyl substances (PFAS) contamination is widespread in our environment and partitioning at interfaces is a major factor that influences their fate and transport within a soil pore space. To develop better PFAS management and remediation strategies, we need to gain a deeper understanding of PFAS soil-porewater partitioning processes in situ. In this study, we investigated the partitioning of PFAS in a spiked agricultural soil and an Aqueous Film-Forming Foam (AFFF) impacted “aged” soil under various soil moisture conditions and when the soil pores were filled with a non-aqueous phase liquid (NAPL). Sulfur (S) K-edge X-ray absorption near edge structure (XANES) spectroscopy was used to probe S speciation in situ, and spectra were analysed applying a Gaussian Curve Fitting (GCF) approach. Six major S species were identified in both soils and PFAS partitioning behaviour was interpreted based on changes in sulfonate fractions, representing sulfonic acid-based PFAS. In the spiked soil, sulfonate fractions increased the most when soil pores had a water saturation ratio (S_W) of 0.25, whereas in the “aged” soil the most significant increase occurred for completely saturated soil pores. These differences were attributed to differing micellar formation behaviours in freshly spiked versus AFFF impacted “aged” soils. A linear correlation was also observed between the ratio of total reduced S and sulfonate fractions against the degree of saturation of “aged” soil. Furthermore, in spiked soil it was observed that a lower percentage NAPL content at S_W = 0.25 led to higher partitioning of sulfonic acid-based PFAS.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104820"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145834055","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatio-temporal dynamics and flux of microplastics in the lower Ganges-Brahmaputra-Meghna River system and estuary","authors":"Md. Jaker Hossain ,&nbsp;Sheikh Aftab Uddin ,&nbsp;Lijun He ,&nbsp;Huahong Shi ,&nbsp;Jing Zhang","doi":"10.1016/j.jconhyd.2025.104830","DOIUrl":"10.1016/j.jconhyd.2025.104830","url":null,"abstract":"<div><div>Rivers are major pathways of land-based plastic debris to the oceans, but limited data exist for microplastic (MP) flux from large river systems. This study examines the spatial and seasonal dynamics of MPs in the Ganges-Brahmaputra-Meghna (GBM) River system and estuary, a key contributor to global marine plastic pollution. MP abundances ranged from 1.53 to 8.13 items/L in the dry season and 2.67 to 7.67 items/L in the wet season, with no significant overall seasonal difference (<em>p</em> &gt; 0.05). The dominated shape and color were<!--> <!-->fiber and blue, respectively, with the size class of 0.02–0.5 mm being predominant. The prevalent polymers during both seasons<!--> <!-->were rayon and polyethylene. MP transported into the Bay of Bengal (BoB) were calculated as 9.42 × 10¹² items/day (1.17 tons/day) during dry season and 33.95 × 10¹² items/day (10.78 tons/day) in wet season indicating that a substantial amount of MPs are being input to<!--> <!-->marine environment from GBM River system compared with other rivers globally. Risk assessments indicated high contamination levels (CF<em>, PLI, and HI</em>) and substantial ecological risks (<em>RI</em>) values<!--> <!-->in the entire study area with maximum pollution level gradient at the Ganges, Meghna and GBM confluence. These findings contribute important quantitative<!--> <!-->information on spatio-temporal patterns and load of MP, necessary for validation of global-level MP flux models and the development of focused mitigation strategies within the GBM basin.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104830"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145850430","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Toward closed-loop remediation: A dynamic optimization approach for hydraulic conductivity estimation and pump-and-treat design","authors":"JunZe Wei ,&nbsp;Simin Jiang ,&nbsp;Qi Liu ,&nbsp;Xun Zhang ,&nbsp;Na Zheng ,&nbsp;Jingwen Xing","doi":"10.1016/j.jconhyd.2026.104852","DOIUrl":"10.1016/j.jconhyd.2026.104852","url":null,"abstract":"<div><div>In the remediation of contaminated sites, the accuracy of the hydraulic conductivity field (K-field) is a critical factor affecting remediation efficiency. Traditional methods, which rely on sparse historical data, short-term pumping tests, and static interpolation methods, often fail to capture heterogeneity of K-fields due to limited monitoring data. This inaccuracy leads to suboptimal remediation designs, resulting in increased costs and reduced efficiency. To address these limitations, this study proposes a dynamic iterative optimization framework that integrates parameter inversion with remediation plan design into a closed-loop system of simulation-observation-update-optimization. The framework iteratively updates the K-field using pilot point parameterization and simulation-optimization techniques, while dynamically adjusting the remediation strategy based on real-time monitoring data. Numerical experiments conducted on a virtual contaminated site demonstrate that the proposed framework significantly improves the accuracy of K-field characterization, as evidenced by decreasing logarithmic root mean square error (LRMSE) and increasing spatial correlation coefficient (SCC) over iterations. Critically, when compared with a conventional static remediation plan that is designed once and executed without updates, the dynamic framework achieves a substantially higher contaminant removal rate while simultaneously reducing the total pumping volume. These results highlight the framework’ s potential to enhance remediation effectiveness and reduce operational costs in heterogeneous aquifers, offering a practical and adaptive solution for complex contaminated site management.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104852"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nitrate dynamics in the Dongjiang River watershed: Human impacts in the context of an Anthropocene River","authors":"Yaotong Gao ,&nbsp;Bingjun Liu ,&nbsp;Qian Tan ,&nbsp;Kai He ,&nbsp;Wei Ouyang ,&nbsp;Yaling Yu","doi":"10.1016/j.jconhyd.2026.104843","DOIUrl":"10.1016/j.jconhyd.2026.104843","url":null,"abstract":"<div><div>Rivers in the Anthropocene are increasingly impacted by human activities, with nitrate (NO₃⁻) pollution posing a significant threat to water quality and ecosystem health. This study investigates the Dongjiang River watershed as a representative example of such systems impacted by human activities. Using nitrate dual isotopes (δ¹⁵N-NO₃⁻ and δ¹⁸O-NO₃⁻) and a Bayesian mixing model (MixSIAR), we identified the sources and transformation processes of NO₃⁻ in the downstream Dongjiang River. Our results indicate that manure and sewage (MS) account for the majority of NO₃⁻ inputs (64.52 %), followed by soil nitrogen (SN) at 18.88 %. The influence of MS is amplified in catchments with higher urbanization, while forested areas show more significant contributions from SN. Seasonal variations in nitrate sources were also observed, with MS dominating during the dry season and SN contributions increasing during the wet season. Nitrification and denitrification were relatively weak during our sampling periods, as indicated by the absence of a characteristic δ¹⁵N-NO₃⁻ versus δ¹⁸O-NO₃⁻ slope (∼50 %) and by low extent of denitrification values at most sites; thus, external inputs were likely the primary drivers of NO₃⁻ dynamics. Furthermore, we link socio-economic factors and water consumption patterns to specific NO₃⁻ sources, highlighting the role of urbanization, economic development, and agricultural practices in shaping nitrate pollution. These findings provide critical insights for managing water quality and mitigating anthropogenic impacts on the Dongjiang River in the Anthropocene.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104843"},"PeriodicalIF":4.4,"publicationDate":"2026-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145977580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}