Journal of contaminant hydrology最新文献_第8页

In situ XANES study of PFAS impacted soils filled with aqueous and non-aqueous phases PFAS对水相和非水相土壤的原位XANES研究。

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-20 DOI: 10.1016/j.jconhyd.2025.104820

Anand Kumar , Md Khairul Alam , Bin Qian , Mike J. Donn , Divina A. Navarro , John L. Rayner , Greg B. Davis , Bruce Cowie , Bobby Pejcic , Steve Fisher

Per- 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.

全氟和多氟烷基物质（PFAS）污染在我们的环境中广泛存在，在界面上的分配是影响其命运和在土壤孔隙空间内运输的主要因素。为了制定更好的PFAS管理和修复策略，我们需要更深入地了解PFAS土壤孔隙水在原位的分配过程。在本研究中，我们研究了在不同土壤湿度条件下，当土壤孔隙被非水相液体（NAPL）填充时，PFAS在尖刺农业土壤中的分配和水成膜泡沫（AFFF）对“老化”土壤的影响。采用硫(S) k边x射线吸收近边结构（XANES）光谱原位探测S物种形成，并采用高斯曲线拟合（GCF）方法对光谱进行分析。在两种土壤中鉴定出6种主要的S物种，并根据磺酸组分的变化解释了PFAS的分配行为，代表了磺酸基PFAS。在尖刺土中，孔隙水饱和比（SW）为0.25时，硫酸盐组分增加最多，而在“老化”土中，孔隙完全饱和时，硫酸盐组分增加最显著。这些差异归因于新钉钉与AFFF影响的“老化”土壤中不同的胶束形成行为。总还原S和硫酸盐组分的比例与“老化”土壤的饱和程度之间也存在线性相关。此外，在钉螺土壤中，当SW = 0.25时，较低的NAPL含量导致了磺酸基PFAS的较高分配。

{"title":"In situ XANES study of PFAS impacted soils filled with aqueous and non-aqueous phases","authors":"Anand Kumar , Md Khairul Alam , Bin Qian , Mike J. Donn , Divina A. Navarro , John L. Rayner , Greg B. Davis , Bruce Cowie , Bobby Pejcic , 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<sub>W</sub>) 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<sub>W</sub> = 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":"2025-12-20","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}

引用次数: 0

Removal of polystyrene nanosphere and fragment from aqueous solutions by magnetic biochar derived from crab shell 磁性生物炭去除水中聚苯乙烯纳米球和碎片

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-18 DOI: 10.1016/j.jconhyd.2025.104810

Yu Wang , Hao Wang , Yirui Xing , Yufei Ren , Zhiyu Liu , Tongyu Zhang , Jingjing Kang , Xiaohui Li

Adsorption by biochar is widely recognized as a promising strategy for micro/nanoplastics removal from aqueous systems. Magnetic biochar derived from crab shell (M-CSBC) was successfully prepared by pyrolysis and subsequent ball milling with magnetic modification, and it was pioneeringly applied for the effective removal of spherical polystyrene nanoplastics (PSNPs) and fragmental polystyrene microplastics (PSMPs) from aquatic environment. M-CSBC exhibited excellent removal for PSNPs/PSMPs with different shape and size. The adsorption process fitted Langmuir model well, and the maximum removal capacities of PSNPs (100 nm) and PSMPs (0.35–0.45 mm) were 90.090 mg/g and 14.472 g/g, respectively. The removal of PSNPs/PSMPs was significantly influenced by variations in pH and salinity, with a more pronounced effect observed for PSNPs compared to PSMPs. M-CSBC was generally more suitable for the neutral acidic, saline aquatic systems. 500 nm NPs were easier to be removed compared with 100 nm NPs, while the removal efficiency of 0.35–0.45 mm PS fragments was larger than that of 0.45–0.60 mm fragments. The removal of PSNPs/PSMPs by M-CSBC were controlled through a combination of physical trapping, chemical adsorption (electrostatic interactions, chemical bonding, complexation, cation-bridging) as well as the magnetization separation. Especially, the real-time observations revealed that both the dispersed M-CSBC and the mixture of M-CSBC and plastic particles behaved akin to a “magnetic mop”, efficiently sweeping up and removing the other plastic particles without enough M-CSBC adsorption. The present findings demonstrate the immense potential of M-CSBC as a highly promising candidate for the efficient microplastics and nanoplastics remediation.

生物炭吸附被广泛认为是一种很有前途的去除水中微/纳米塑料的方法。以蟹壳为原料，通过热解、球磨和磁改性制备了磁性生物炭（M-CSBC），并将其率先应用于水生环境中球形聚苯乙烯纳米塑料（PSNPs）和片状聚苯乙烯微塑料（PSMPs）的有效去除。M-CSBC对不同形状和大小的psnp /PSMPs均表现出良好的去除效果。吸附过程符合Langmuir模型，对psnp （100 nm）和PSMPs （0.35 ~ 0.45 mm）的最大去除率分别为90.090 mg/g和14.472 g/g。PSNPs/PSMPs的去除受到pH和盐度变化的显著影响，与PSMPs相比，PSNPs的效果更为明显。M-CSBC一般更适合于中性酸性、咸水系统。与100 nm的NPs相比，500 nm的NPs更容易被去除，而0.35-0.45 mm的PS片段的去除效率大于0.45-0.60 mm的片段。M-CSBC对PSNPs/PSMPs的去除是通过物理捕获、化学吸附（静电相互作用、化学键、络合、阳离子桥接）和磁化分离的组合来控制的。特别是，实时观察显示，分散的M-CSBC和M-CSBC与塑料颗粒的混合物的行为类似于“磁性拖把”，可以有效地清除其他塑料颗粒，而没有足够的M-CSBC吸附。目前的研究结果表明，M-CSBC作为一种非常有前途的高效微塑料和纳米塑料修复材料具有巨大的潜力。

{"title":"Removal of polystyrene nanosphere and fragment from aqueous solutions by magnetic biochar derived from crab shell","authors":"Yu Wang , Hao Wang , Yirui Xing , Yufei Ren , Zhiyu Liu , Tongyu Zhang , Jingjing Kang , Xiaohui Li","doi":"10.1016/j.jconhyd.2025.104810","DOIUrl":"10.1016/j.jconhyd.2025.104810","url":null,"abstract":"<div><div>Adsorption by biochar is widely recognized as a promising strategy for micro/nanoplastics removal from aqueous systems. Magnetic biochar derived from crab shell (M-CSBC) was successfully prepared by pyrolysis and subsequent ball milling with magnetic modification, and it was pioneeringly applied for the effective removal of spherical polystyrene nanoplastics (PSNPs) and fragmental polystyrene microplastics (PSMPs) from aquatic environment. M-CSBC exhibited excellent removal for PSNPs/PSMPs with different shape and size. The adsorption process fitted Langmuir model well, and the maximum removal capacities of PSNPs (100 nm) and PSMPs (0.35–0.45 mm) were 90.090 mg/g and 14.472 g/g, respectively. The removal of PSNPs/PSMPs was significantly influenced by variations in pH and salinity, with a more pronounced effect observed for PSNPs compared to PSMPs. M-CSBC was generally more suitable for the neutral acidic, saline aquatic systems. 500 nm NPs were easier to be removed compared with 100 nm NPs, while the removal efficiency of 0.35–0.45 mm PS fragments was larger than that of 0.45–0.60 mm fragments. The removal of PSNPs/PSMPs by M-CSBC were controlled through a combination of physical trapping, chemical adsorption (electrostatic interactions, chemical bonding, complexation, cation-bridging) as well as the magnetization separation. Especially, the real-time observations revealed that both the dispersed M-CSBC and the mixture of M-CSBC and plastic particles behaved akin to a “magnetic mop”, efficiently sweeping up and removing the other plastic particles without enough M-CSBC adsorption. The present findings demonstrate the immense potential of M-CSBC as a highly promising candidate for the efficient microplastics and nanoplastics remediation.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104810"},"PeriodicalIF":4.4,"publicationDate":"2025-12-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145837534","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}

引用次数: 0

Research on the carbon cycle of surface water-groundwater in the Jianghan Dongting Plain of the Yangtze River Basin, China 长江流域江汉洞庭平原地表水-地下水碳循环研究

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-17 DOI: 10.1016/j.jconhyd.2025.104812

Meiyan Hu , Peijiang Zhou , Chao Meng , Xiaobin Li , Xiaoxi Chen , Jingyi Xie , Shengkai Cao , Xiaodi Zhang , Zhen Ni , Guangshui Na

Carbon cycle research is the core foundation for understanding the root causes of climate change and developing effective emission reduction strategies. Carbon source-sink dynamics in the water ecologic environment is the key component of the carbon cycle in basins. Jianghan Dongting Plain of the Yangtze River Basin is rich in water resources, but lacks a comprehensive understanding on the carbon source-sink dynamics of water environment. The study integrated literature data and self-tested data to research the carbon source-sink dynamics in surface water and groundwater in the Jianghan Dongting Plain. The study found that there was a coupling effect of HCO₃⁻ and DOC between SW (surface water) and GW (groundwater) in the Jianghan-Dongting Plain of the central Yangtze River Basin. The HCO₃⁻ in surface water may come from the recharge of groundwater, and the DOC in the groundwater may come from the recharge of surface water. In addition, the high concentration of NH₄⁺-N in groundwater inhibited the release of DOC from the sediment into the groundwater. Decreasing of situation index (SI) values of calcite and dolomite from west to east indicated that under the coupling effect between surface water and groundwater, the water carbonate interaction was enhanced, leading to the carbon sink changing to be carbon source from west to east. The study clarified the spatial pattern of regional carbon effects of “ west sink and east source” for the first time, elevating carbon cycle research from a single water body to a system level of “surface water groundwater continuum”, successfully connecting micro biogeochemical processes with macro regional carbon cycle patterns, which is of great significance for carbon cycling research in the Yangtze River Basin and predicting future environmental changes.

碳循环研究是认识气候变化的根本原因，制定有效减排战略的核心基础。水生态环境中的碳源汇动态是流域碳循环的关键组成部分。长江流域江汉洞庭平原水资源丰富，但缺乏对水环境碳源汇动态的全面认识。本研究结合文献资料和自检资料，对江汉洞庭平原地表水和地下水碳源汇动态进行了研究。研究发现，长江流域中部江汉—洞庭平原地表水SW与地下水GW之间存在HCO3−与DOC的耦合效应。地表水中的HCO3−可能来自地下水的补给，地下水中的DOC可能来自地表水的补给。此外，地下水中高浓度的NH4+-N抑制了沉积物中DOC向地下水的释放。方解石和白云岩的SI值自西向东递减，说明在地表水和地下水的耦合作用下，水-碳酸盐相互作用增强，导致碳汇自西向东转变为碳源。该研究首次明确了“西汇东源”区域碳效应的空间格局，将碳循环研究从单一水体提升到“地表水-地下水连续体”的系统层面，成功地将微观生物地球化学过程与宏观区域碳循环格局联系起来，对长江流域碳循环研究和预测未来环境变化具有重要意义。

{"title":"Research on the carbon cycle of surface water-groundwater in the Jianghan Dongting Plain of the Yangtze River Basin, China","authors":"Meiyan Hu , Peijiang Zhou , Chao Meng , Xiaobin Li , Xiaoxi Chen , Jingyi Xie , Shengkai Cao , Xiaodi Zhang , Zhen Ni , Guangshui Na","doi":"10.1016/j.jconhyd.2025.104812","DOIUrl":"10.1016/j.jconhyd.2025.104812","url":null,"abstract":"<div><div>Carbon cycle research is the core foundation for understanding the root causes of climate change and developing effective emission reduction strategies. Carbon source-sink dynamics in the water ecologic environment is the key component of the carbon cycle in basins. Jianghan Dongting Plain of the Yangtze River Basin is rich in water resources, but lacks a comprehensive understanding on the carbon source-sink dynamics of water environment. The study integrated literature data and self-tested data to research the carbon source-sink dynamics in surface water and groundwater in the Jianghan Dongting Plain. The study found that there was a coupling effect of HCO<sub>3</sub><sup>−</sup> and DOC between SW (surface water) and GW (groundwater) in the Jianghan-Dongting Plain of the central Yangtze River Basin. The HCO<sub>3</sub><sup>−</sup> in surface water may come from the recharge of groundwater, and the DOC in the groundwater may come from the recharge of surface water. In addition, the high concentration of NH<sub>4</sub><sup>+</sup>-N in groundwater inhibited the release of DOC from the sediment into the groundwater. Decreasing of situation index (SI) values of calcite and dolomite from west to east indicated that under the coupling effect between surface water and groundwater, the water carbonate interaction was enhanced, leading to the carbon sink changing to be carbon source from west to east. The study clarified the spatial pattern of regional carbon effects of “ west sink and east source” for the first time, elevating carbon cycle research from a single water body to a system level of “surface water groundwater continuum”, successfully connecting micro biogeochemical processes with macro regional carbon cycle patterns, which is of great significance for carbon cycling research in the Yangtze River Basin and predicting future environmental changes.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104812"},"PeriodicalIF":4.4,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788227","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}

引用次数: 0

Seasonal variability in the hydrogeochemical behavior and metal fluxes of acid mine drainage: Implications for long-term output and treatment 酸性矿井水的水文地球化学行为和金属通量的季节变化：对长期产出和处理的影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-17 DOI: 10.1016/j.jconhyd.2025.104818

David M. Singer, Rachel Izworski, Annika Dudik, Allyson C. Tessin

The timeframe for when water quality impairment from acid mine drainage (AMD) from abandoned coal mines might end is often poorly constrained. The response of AMD composition to changes in discharge can provide insight into how mines store and release water and solutes. This work aimed to determine seasonal variability, hydrogeochemical behavior, and metal fluxes from two abandoned coal mines in Appalachian Ohio that represent end-member hydrologic conditions within the Huff Run (HR, groundwater-fed) and Yellow Creek (YC, surface water-fed) watersheds, by: (1) monitoring AMD output to establish seasonal variability; (2) comparing current output to publicly available historical data; and (3) linking metal loadings in the AMD from each mine to characteristics of the coal and abandoned mine works. The HR AMD was dominated by chemostasis (“pipe-full”), whereas the YC AMD was dominated by dilution (“not pipe-full”). For HR, the combination of continuously flooded mineworks recharged primarily by groundwater combined with the presence of fine-grained, diffusely disseminated pyrite in the host rock results in slower AMD production, although shorter timeframe for water quality impairment (decades) given current conditions. In contrast, the faster pace of YC AMD depletion is likely due to the combination of pseudokarstic flow conditions fed by surface water with large, seasonal pulses of dissolved metals from the weathering of coarse-grained aggregates of pyrite but a longer timeframe for AMD impairment to cease (decades to centuries). These results highlight the importance of establishing how the combination of local and regional conditions influence the timeframe for on-going AMD production.

废弃煤矿酸性矿井水（AMD）造成的水质损害何时可能结束的时间框架往往缺乏约束。AMD成分对排放变化的响应可以深入了解矿山如何储存和释放水和溶质。本研究旨在确定俄亥俄州阿巴拉契亚两个废弃煤矿的季节变化、水文地球化学行为和金属通量，这些煤矿代表了Huff Run （HR，地下水）和Yellow Creek （YC，地表水）流域的末端水文条件，方法如下：(1)监测AMD输出以建立季节变化；(2)将当前产出与公开可用的历史数据进行比较；(3)将各矿山矿山中金属的含量与煤炭和废弃矿山的特点联系起来。HR型AMD以化学平衡（“满管”）为主，而YC型AMD以稀释（“不满管”）为主。对于HR来说，持续被水淹没的矿山主要由地下水补给，再加上在宿主岩石中存在细粒、弥散分布的黄铁矿，导致AMD的生产速度较慢，尽管在目前的条件下，水质损害的时间较短（几十年）。相比之下，YC AMD消耗的速度更快可能是由于地表水提供的假岩溶流条件与来自粗粒黄铁矿集合体风化的溶解金属的大量季节性脉冲相结合，但AMD损害停止的时间较长（数十年至数百年）。这些结果突出了确定当地和区域条件如何结合影响正在进行的AMD生产的时间框架的重要性。

{"title":"Seasonal variability in the hydrogeochemical behavior and metal fluxes of acid mine drainage: Implications for long-term output and treatment","authors":"David M. Singer, Rachel Izworski, Annika Dudik, Allyson C. Tessin","doi":"10.1016/j.jconhyd.2025.104818","DOIUrl":"10.1016/j.jconhyd.2025.104818","url":null,"abstract":"<div><div>The timeframe for when water quality impairment from acid mine drainage (AMD) from abandoned coal mines might end is often poorly constrained. The response of AMD composition to changes in discharge can provide insight into how mines store and release water and solutes. This work aimed to determine seasonal variability, hydrogeochemical behavior, and metal fluxes from two abandoned coal mines in Appalachian Ohio that represent end-member hydrologic conditions within the Huff Run (HR, groundwater-fed) and Yellow Creek (YC, surface water-fed) watersheds, by: (1) monitoring AMD output to establish seasonal variability; (2) comparing current output to publicly available historical data; and (3) linking metal loadings in the AMD from each mine to characteristics of the coal and abandoned mine works. The HR AMD was dominated by chemostasis (“pipe-full”), whereas the YC AMD was dominated by dilution (“not pipe-full”). For HR, the combination of continuously flooded mineworks recharged primarily by groundwater combined with the presence of fine-grained, diffusely disseminated pyrite in the host rock results in slower AMD production, although shorter timeframe for water quality impairment (decades) given current conditions. In contrast, the faster pace of YC AMD depletion is likely due to the combination of pseudokarstic flow conditions fed by surface water with large, seasonal pulses of dissolved metals from the weathering of coarse-grained aggregates of pyrite but a longer timeframe for AMD impairment to cease (decades to centuries). These results highlight the importance of establishing how the combination of local and regional conditions influence the timeframe for on-going AMD production.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104818"},"PeriodicalIF":4.4,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788226","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}

引用次数: 0

Enhancing urban river water quality in Indonesia using mineral wool: Long-term field performance, seasonal dynamics, and multi-index assessment 利用矿棉改善印度尼西亚城市河流水质：长期实地表现、季节动态和多指数评估

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-17 DOI: 10.1016/j.jconhyd.2025.104819

Wisnu Prayogo , Prayatni Soewondo , Gerry Andhikaputra , Sarra Rahmadani , Laili Fitria , Zhilli Izzadati Khairuni , I. Made Wahyu Widyarsana , Muammar Qadafi , Novi Fitria , Januar Parlaungan Siregar , Aristya Ardhitama

Urban rivers in rapidly growing tropical cities face persistent pollution pressures and limited wastewater infrastructure, demanding scalable in-stream restoration approaches. This study presents the first long-duration, field-scale deployment of mineral wool (MW) in a tropical monsoon river system, evaluating pollutant attenuation and seasonal treatment dynamics in the Cikapayang River, Bandung, Indonesia. Two MW configurations were installed in cascade channels without pumping, chemical inputs, or hydraulic control, and monitored across wet and dry seasons. Water quality was assessed using 11 physical and chemical parameters and interpreted through four Water Quality Indices (PI, STORET, CCME-WQI, NSF-WQI) to benchmark regulatory and international assessment frameworks. MW achieved mean pollutant removal of 43.51 %, improving river status from heavily polluted to moderate/lightly polluted. Dry-season performance intensified due to longer hydraulic retention and mature biofilms, yielding up to 61.52 % COD and 50.28 % TN removal, while wet-season turbulence reduced residence time but retained stable performance. Microstructural imaging confirmed a transition from mineral-mediated filtration and cation exchange to biofilm-driven nitrification–denitrification. Among WQIs, CCME-WQI exhibited the highest sensitivity, improving from “very poor” to “poor–fair (44.24)”, while PI offered more optimistic classifications. Findings demonstrate MW as an effective, low-energy, circular-material solution for decentralized urban river treatment under monsoon hydrology. This work bridges the gap between controlled experiments and real-river implementation, providing performance and assessment benchmarks for scalable nature-based interventions in developing regions. Future studies should address media longevity, regeneration, and hydrodynamic optimization.

在快速发展的热带城市中，城市河流面临着持续的污染压力和有限的废水基础设施，需要可扩展的河内修复方法。本研究首次在热带季风河流系统中进行了长时间、现场规模的矿棉（MW）部署，评估了印度尼西亚万隆Cikapayang河的污染物衰减和季节性处理动态。两个MW配置安装在梯级通道中，无需泵送、化学输入或液压控制，并在干湿季节进行监测。采用11个物理和化学参数对水质进行评估，并通过四个水质指数（PI， STORET, CCME-WQI, NSF-WQI）进行解释，以基准监管和国际评估框架。MW平均污染物去除率达到43.51%，使河流从重度污染改善到中度/轻度污染。由于水力滞留时间延长和生物膜成熟，旱季性能增强，COD去除率高达61.52%，TN去除率高达50.28%，而雨季湍流减少了停留时间，但性能保持稳定。显微结构成像证实了从矿物介导的过滤和阳离子交换到生物膜驱动的硝化-反硝化的转变。在wqi中，CCME-WQI的敏感性最高，从“非常差”提高到“差-一般”（44.24），而PI的分类更为乐观。研究结果表明，MW是季风水文条件下分散城市河流处理的有效、低能耗、循环材料解决方案。这项工作弥合了对照实验和实际河流实施之间的差距，为发展中地区可扩展的基于自然的干预措施提供了绩效和评估基准。未来的研究应着眼于介质寿命、再生和流体动力学优化。

{"title":"Enhancing urban river water quality in Indonesia using mineral wool: Long-term field performance, seasonal dynamics, and multi-index assessment","authors":"Wisnu Prayogo , Prayatni Soewondo , Gerry Andhikaputra , Sarra Rahmadani , Laili Fitria , Zhilli Izzadati Khairuni , I. Made Wahyu Widyarsana , Muammar Qadafi , Novi Fitria , Januar Parlaungan Siregar , Aristya Ardhitama","doi":"10.1016/j.jconhyd.2025.104819","DOIUrl":"10.1016/j.jconhyd.2025.104819","url":null,"abstract":"<div><div>Urban rivers in rapidly growing tropical cities face persistent pollution pressures and limited wastewater infrastructure, demanding scalable in-stream restoration approaches. This study presents the first long-duration, field-scale deployment of mineral wool (MW) in a tropical monsoon river system, evaluating pollutant attenuation and seasonal treatment dynamics in the Cikapayang River, Bandung, Indonesia. Two MW configurations were installed in cascade channels without pumping, chemical inputs, or hydraulic control, and monitored across wet and dry seasons. Water quality was assessed using 11 physical and chemical parameters and interpreted through four Water Quality Indices (PI, STORET, CCME-WQI, NSF-WQI) to benchmark regulatory and international assessment frameworks. MW achieved mean pollutant removal of 43.51 %, improving river status from heavily polluted to moderate/lightly polluted. Dry-season performance intensified due to longer hydraulic retention and mature biofilms, yielding up to 61.52 % COD and 50.28 % TN removal, while wet-season turbulence reduced residence time but retained stable performance. Microstructural imaging confirmed a transition from mineral-mediated filtration and cation exchange to biofilm-driven nitrification–denitrification. Among WQIs, CCME-WQI exhibited the highest sensitivity, improving from “very poor” to “poor–fair (44.24)”, while PI offered more optimistic classifications. Findings demonstrate MW as an effective, low-energy, circular-material solution for decentralized urban river treatment under monsoon hydrology. This work bridges the gap between controlled experiments and real-river implementation, providing performance and assessment benchmarks for scalable nature-based interventions in developing regions. Future studies should address media longevity, regeneration, and hydrodynamic optimization.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104819"},"PeriodicalIF":4.4,"publicationDate":"2025-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788160","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}

引用次数: 0

Adsorption behavior of triclosan by different microplastics and the impact of water chemistry 不同微塑料对三氯生的吸附行为及其对水化学的影响。

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-16 DOI: 10.1016/j.jconhyd.2025.104815

Yandan Li , Tianxiang Xia , Dan Zhang , Danyang Zhang , Miao Li

The mechanisms of triclosan (TCS) adsorption onto polyamide (PA), polystyrene (PS), polyvinylchloride (PVC) and low-density polyethylene (LDPE) microplastics (MPs) were investigated, along with the effects of solution pH, ionic strength, and dissolved organic matter (DOM). The Linear model better described TCS adsorption isotherms suggesting that hydrophobic partitioning was the primary mechanism for TCS adsorption, while the Freundlich and Langmuir model fittings showed that TCS adsorption onto MPs was favorable. Following normalization by the specific surface area (SSA) of MPs, adsorption distribution coefficient (K_d) values of 105.70, 0.56, 0.20, and 0.08 L/m² were determined for PA, PS, PVC, and LDPE MPs, respectively. Hydrophobic interaction was the main adsorption mechanism, although other mechanisms, governed by the specific structure and functional groups of the MPs, also contributed. These included the formation of hydrogen bonds between the –OH on TCS (H-bond-donating) and the amide groups on PA (H-bond-accepting), and the π-π interactions between the benzene rings of PS and TCS, and hydrogen bonds between -OH on TCS and –COO^-/–COOH on PVC MPs. TCS adsorption by MPs was found to be pH-dependent, indicating that TCS⁰ was the main species involved in adsorption. The effects of ionic strength on TCS adsorption were not significant and therefore could be ignored. Humic acid (HA) impeded the adsorption of TCS by PA, PS, and LDPE MPs, potentially due to the hydrophobic interactions of HA with the three MPs, the hydrogen bonds with PA MPs, and the π-π interactions with PS MPs, all of which competed with TCS for adsorption sites. Fulvic acid (FA) inhibited TCS adsorption onto PS MPs, as FA could be sorbed by PS MPs through π-π interactions, competing with TCS for adsorption sites. These findings improve the accuracy of risk evaluations for organic pollutants such as TCS when co-occurring with MPs, furthering our understanding of the impacts of complex pollutant mixtures on both human and environmental health.

研究了三氯生（TCS）在聚酰胺（PA）、聚苯乙烯（PS）、聚氯乙烯（PVC）和低密度聚乙烯（LDPE）微塑料（MPs）上的吸附机理，以及溶液pH、离子强度和溶解有机物（DOM）的影响。线性模型较好地描述了TCS的吸附等温线，表明疏水分配是TCS吸附的主要机制，而Freundlich和Langmuir模型拟合表明TCS在MPs上的吸附是有利的。经MPs的比表面积（SSA）归一化后，PA、PS、PVC和LDPE MPs的吸附分布系数（Kd）分别为105.70、0.56、0.20和0.08 L/m2。疏水相互作用是主要的吸附机制，尽管由MPs的特定结构和官能团支配的其他机制也起作用。其中包括TCS上的- oh与PA上的酰胺基团之间形成氢键（供氢键），PS和TCS的苯环之间形成π-π相互作用，以及TCS上的- oh与PVC MPs上的- coo -/- cooh之间形成氢键。发现MPs对TCS的吸附与ph有关，表明TCS0是主要的吸附物质。离子强度对TCS吸附的影响不显著，可以忽略。腐植酸（HA）阻碍了PA、PS和LDPE MPs对TCS的吸附，这可能是由于HA与三种MPs的疏水相互作用、与PA MPs的氢键以及与PS MPs的π-π相互作用，这些相互作用都与TCS争夺吸附位点。富里酸（FA）抑制了TCS在PS MPs上的吸附，因为FA可以通过π-π相互作用被PS MPs吸附，与TCS竞争吸附位点。这些发现提高了有机污染物（如TCS）与MPs共存时风险评估的准确性，进一步加深了我们对复杂污染物混合物对人类和环境健康影响的理解。

{"title":"Adsorption behavior of triclosan by different microplastics and the impact of water chemistry","authors":"Yandan Li , Tianxiang Xia , Dan Zhang , Danyang Zhang , Miao Li","doi":"10.1016/j.jconhyd.2025.104815","DOIUrl":"10.1016/j.jconhyd.2025.104815","url":null,"abstract":"<div><div>The mechanisms of triclosan (TCS) adsorption onto polyamide (PA), polystyrene (PS), polyvinylchloride (PVC) and low-density polyethylene (LDPE) microplastics (MPs) were investigated, along with the effects of solution pH, ionic strength, and dissolved organic matter (DOM). The Linear model better described TCS adsorption isotherms suggesting that hydrophobic partitioning was the primary mechanism for TCS adsorption, while the Freundlich and Langmuir model fittings showed that TCS adsorption onto MPs was favorable. Following normalization by the specific surface area (SSA) of MPs, adsorption distribution coefficient (K<sub>d</sub>) values of 105.70, 0.56, 0.20, and 0.08 L/m<sup>2</sup> were determined for PA, PS, PVC, and LDPE MPs, respectively. Hydrophobic interaction was the main adsorption mechanism, although other mechanisms, governed by the specific structure and functional groups of the MPs, also contributed. These included the formation of hydrogen bonds between the –OH on TCS (H-bond-donating) and the amide groups on PA (H-bond-accepting), and the π-π interactions between the benzene rings of PS and TCS, and hydrogen bonds between -OH on TCS and –COO<sup>-</sup>/–COOH on PVC MPs. TCS adsorption by MPs was found to be pH-dependent, indicating that TCS<sup>0</sup> was the main species involved in adsorption. The effects of ionic strength on TCS adsorption were not significant and therefore could be ignored. Humic acid (HA) impeded the adsorption of TCS by PA, PS, and LDPE MPs, potentially due to the hydrophobic interactions of HA with the three MPs, the hydrogen bonds with PA MPs, and the π-π interactions with PS MPs, all of which competed with TCS for adsorption sites. Fulvic acid (FA) inhibited TCS adsorption onto PS MPs, as FA could be sorbed by PS MPs through π-π interactions, competing with TCS for adsorption sites. These findings improve the accuracy of risk evaluations for organic pollutants such as TCS when co-occurring with MPs, furthering our understanding of the impacts of complex pollutant mixtures on both human and environmental health.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104815"},"PeriodicalIF":4.4,"publicationDate":"2025-12-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145819491","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}

引用次数: 0

Directional injection-driven contaminants transport in groundwater system with asymptotically varying dispersion coefficients 离散系数渐近变化的地下水系统中定向注入驱动的污染物运移

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104813

S. Nagouda Smita, R. Iyer Aiswarya

This work examines the effect of asymptotic dispersion for different contaminants, like heavy metals, biological, and radiological types, in heterogeneous groundwater systems. The migration of contaminants within groundwater systems is controlled by advection, dispersion, and sorption phenomena, and these mechanisms are mathematically modeled using the Advection-Dispersion Equation (ADE). Using the Thomas algorithm, a numerical simulation with the Peaceman - Rachford Alternating Direction Implicit (PR-ADI) scheme is applied to solve the ADE under the directional injection boundary (axial input sources). The study on asymptotic dispersion coefficients revealed a broader plume evolution. Non-linear sorption models depended on the saturation limit, and various parameters revealed physically relevant results. The iso-concentration figures depict flow patterns for diverse directional hydrological inflows, supporting stability interpretations. This study introduces a computational approach for modeling contaminant transport in groundwater systems, emphasizing asymptotic field conditions that introduce heterogeneity, coupled with nonlinear sorption effects on the plume morphology. The results highlight how plume morphology responds to variable dispersion and velocity, offering guidance for field-scale aquifer analysis and water quality management. The study is also aligned with Sustainable Development Goal 6 - Clean water and sanitation.

本研究考察了非均质地下水系统中不同污染物（如重金属、生物和放射类型）的渐近分散效应。地下水系统中污染物的迁移受平流、弥散和吸附现象的控制，这些机制使用平流-弥散方程（ADE）进行数学建模。采用Thomas算法，采用Peaceman - Rachford交替方向隐式（r - adi）格式进行数值模拟，求解定向注入边界（轴向输入源）下的ADE。渐近色散系数的研究揭示了更广泛的羽流演化。非线性吸附模型依赖于饱和极限，各种参数揭示了物理相关的结果。等浓度图描绘了不同方向水文流入的流动模式，支持稳定性解释。本研究引入了一种模拟地下水系统中污染物运移的计算方法，强调了引入非均质性的渐近场条件，以及对羽流形态的非线性吸收效应。研究结果突出了羽流形态对不同分散和速度的响应，为现场尺度的含水层分析和水质管理提供了指导。这项研究也符合可持续发展目标6——清洁水和卫生设施。

{"title":"Directional injection-driven contaminants transport in groundwater system with asymptotically varying dispersion coefficients","authors":"S. Nagouda Smita, R. Iyer Aiswarya","doi":"10.1016/j.jconhyd.2025.104813","DOIUrl":"10.1016/j.jconhyd.2025.104813","url":null,"abstract":"<div><div>This work examines the effect of asymptotic dispersion for different contaminants, like heavy metals, biological, and radiological types, in heterogeneous groundwater systems. The migration of contaminants within groundwater systems is controlled by advection, dispersion, and sorption phenomena, and these mechanisms are mathematically modeled using the Advection-Dispersion Equation (ADE). Using the Thomas algorithm, a numerical simulation with the Peaceman - Rachford Alternating Direction Implicit (PR-ADI) scheme is applied to solve the ADE under the directional injection boundary (axial input sources). The study on asymptotic dispersion coefficients revealed a broader plume evolution. Non-linear sorption models depended on the saturation limit, and various parameters revealed physically relevant results. The iso-concentration figures depict flow patterns for diverse directional hydrological inflows, supporting stability interpretations. This study introduces a computational approach for modeling contaminant transport in groundwater systems, emphasizing asymptotic field conditions that introduce heterogeneity, coupled with nonlinear sorption effects on the plume morphology. The results highlight how plume morphology responds to variable dispersion and velocity, offering guidance for field-scale aquifer analysis and water quality management. The study is also aligned with Sustainable Development Goal 6 - Clean water and sanitation.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104813"},"PeriodicalIF":4.4,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788159","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}

引用次数: 0

Spatiotemporal assessment of toxic metals in total suspanded matter and surface sediments of Borçka Reservoir (Türkiye): Tracing pollution and ecological risk implications borka水库（trkiye）总悬浮物和表层沉积物中有毒金属的时空评价：追踪污染和生态风险影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104814

Koray Özşeker , Yahya Terzi , Coşkun Erüz

This study investigates the spatiotemporal variations of toxic metals (Cu, Pb, Zn, Ni, As) in both suspended particulate matter (SPM) and surface sediments of the Borçka Reservoir (Türkiye) to trace pollution dynamics and evaluate ecological risks. The Borçka Reservoir, located in the southeastern Black Sea basin, is an ecologically and hydrologically important freshwater system affected by intensive human activities. Seasonal sampling was performed at four representative stations throughout 2023. The highest metal enrichment was observed in the upstream region, particularly during autumn, indicating the influence of inflowing waters from the Murgul Stream, a major tributary draining mining areas and discharging into the reservoir. Maximum sediment concentrations reached 446.5 μg/g for Cu, 170.7 μg/g for Pb, and 356.33 μ/kg for Zn, exceeding the Probable Effect Level (PEL; Cu: 197, Pb: 91.3, Zn: 315 μg/g) and Effect Range Median (ERM; Cu: 270, Pb: 218, Zn: 410 μg/g) thresholds of sediment quality guidelines. Enrichment and contamination factors classified Cu as “extremely severe” (class 6), while ecological risk (Er) and toxic risk (TRI) values revealed moderate to considerable risks for Cu and Pb. In SPM, metals also showed autumnal peaks. Physicochemical parameters (pH: 8.17–8.53; TOC: 0.52–0.93%) strongly influenced metal retention. The integrated assessment highlights spatiotemporal heterogeneity of metal pollution and emphasizes the need for continuous monitoring and source-based management strategies for sustainable reservoir ecosystems.

研究了borka水库（trkiye）悬浮颗粒物（SPM）和表层沉积物中有毒金属（Cu、Pb、Zn、Ni、As）的时空变化规律，以追踪污染动态并评价生态风险。borka水库位于黑海盆地东南部，是一个受人类活动强烈影响的重要的生态和水文淡水系统。整个2023年在四个代表性站点进行了季节性采样。在上游地区观察到最高的金属富集，特别是在秋季，这表明来自穆尔古尔河的流入水的影响，穆尔古尔河是一条主要支流，为矿区排水并排入水库。最大沉积物浓度Cu为446.5 μg/g， Pb为170.7 μg/g， Zn为356.33 μ/kg，超过了沉积物质量指南的可能影响水平（PEL; Cu: 197, Pb: 91.3, Zn: 315 μg/g）和影响范围中位数（ERM; Cu: 270, Pb: 218, Zn: 410 μg/g）阈值。富集和污染因子将Cu列为“极严重”（6级），而生态风险（Er）和毒性风险（TRI）值显示Cu和Pb的中度至相当风险。在SPM中，金属也出现了秋季峰值。理化参数（pH: 8.17-8.53; TOC: 0.52-0.93%）强烈影响金属的保留。综合评价强调了金属污染的时空异质性，强调了对可持续水库生态系统进行持续监测和基于源头的管理战略的必要性。

{"title":"Spatiotemporal assessment of toxic metals in total suspanded matter and surface sediments of Borçka Reservoir (Türkiye): Tracing pollution and ecological risk implications","authors":"Koray Özşeker , Yahya Terzi , Coşkun Erüz","doi":"10.1016/j.jconhyd.2025.104814","DOIUrl":"10.1016/j.jconhyd.2025.104814","url":null,"abstract":"<div><div>This study investigates the spatiotemporal variations of toxic metals (Cu, Pb, Zn, Ni, As) in both suspended particulate matter (SPM) and surface sediments of the Borçka Reservoir (Türkiye) to trace pollution dynamics and evaluate ecological risks. The Borçka Reservoir, located in the southeastern Black Sea basin, is an ecologically and hydrologically important freshwater system affected by intensive human activities. Seasonal sampling was performed at four representative stations throughout 2023. The highest metal enrichment was observed in the upstream region, particularly during autumn, indicating the influence of inflowing waters from the Murgul Stream, a major tributary draining mining areas and discharging into the reservoir. Maximum sediment concentrations reached 446.5 μg/g for Cu, 170.7 μg/g for Pb, and 356.33 μ/kg for Zn, exceeding the Probable Effect Level (PEL; Cu: 197, Pb: 91.3, Zn: 315 μg/g) and Effect Range Median (ERM; Cu: 270, Pb: 218, Zn: 410 μg/g) thresholds of sediment quality guidelines. Enrichment and contamination factors classified Cu as “extremely severe” (class 6), while ecological risk (Er) and toxic risk (TRI) values revealed moderate to considerable risks for Cu and Pb. In SPM, metals also showed autumnal peaks. Physicochemical parameters (pH: 8.17–8.53; TOC: 0.52–0.93%) strongly influenced metal retention. The integrated assessment highlights spatiotemporal heterogeneity of metal pollution and emphasizes the need for continuous monitoring and source-based management strategies for sustainable reservoir ecosystems.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104814"},"PeriodicalIF":4.4,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788230","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}

引用次数: 0

Density-dependent flow, solute transport and mixing in the Fraser River delta aquifer 弗雷泽河三角洲含水层的密度依赖性流动、溶质运输和混合

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104816

Yaguang Zhu , Kun Jia , Roger D. Beckie

Groundwater flow in coastal aquifers is influenced by density differences between freshwater and saline water, forming a complex density-dependent flow system. The relatively narrow zone where freshwater and saline water mix is the location of strong geochemical gradients, which can drive reactions. Understanding the dynamics of this mixing zone is crucial to understand the biogeochemical reactions that occur during saline intrusion. In this study, we characterized flow and dispersive mixing in a confined sand aquifer subjected to saline intrusion, using both field observations and numerical modeling. Observations from an extensive monitoring network revealed a saline wedge extending approximately 500 m inland. We simulated density-dependent flow with MIN3P and used PEST++ to estimate dispersivity and diffusion from field observations. In effect, we use salinity data to measure the dispersivity through inverse modeling. The longitudinal and transverse dispersivity were calibrated at 0.1 m and 0.001 m, respectively, while the molecular diffusion coefficient was 1.2 × 10⁻⁹ m²/s. Sensitivity analyses show that transverse dispersivity affects mixing-zone characteristics more than longitudinal dispersivity. Our results highlight the importance of accurately estimating dispersivity values to model the width of the mixing zone, which strongly controls geochemical reactions at the site. These findings provide insights into the processes driving freshwater–saline water mixing in coastal aquifers and offer guidance for future modeling studies on geochemical dynamics during saline intrusion.

沿海含水层的地下水流动受到淡水和咸水密度差的影响，形成了一个复杂的密度依赖流动系统。相对狭窄的淡水和咸水混合带是地球化学梯度强的位置，可以驱动反应。了解这一混合带的动力学对于理解盐水侵入过程中发生的生物地球化学反应至关重要。在这项研究中，我们采用现场观测和数值模拟的方法，对受盐水入侵的承压砂含水层的流动和分散混合进行了表征。来自广泛监测网络的观测显示，一个向内陆延伸约500米的盐楔。我们用MIN3P模拟了密度相关的流动，并使用PEST++从现场观测中估计了分散性和扩散。实际上，我们使用盐度数据通过逆建模来测量分散性。纵向和横向色散分别标定为0.1 m和0.001 m，分子扩散系数为1.2 × 10−9 m2/s。灵敏度分析表明，横向色散比纵向色散对混合区特性的影响更大。我们的研究结果强调了准确估计色散值对模拟混合带宽度的重要性，混合带宽度强烈地控制着现场的地球化学反应。这些发现为了解沿海含水层淡水-咸水混合的过程提供了见解，并为未来盐水入侵过程中地球化学动力学的建模研究提供了指导。

{"title":"Density-dependent flow, solute transport and mixing in the Fraser River delta aquifer","authors":"Yaguang Zhu , Kun Jia , Roger D. Beckie","doi":"10.1016/j.jconhyd.2025.104816","DOIUrl":"10.1016/j.jconhyd.2025.104816","url":null,"abstract":"<div><div>Groundwater flow in coastal aquifers is influenced by density differences between freshwater and saline water, forming a complex density-dependent flow system. The relatively narrow zone where freshwater and saline water mix is the location of strong geochemical gradients, which can drive reactions. Understanding the dynamics of this mixing zone is crucial to understand the biogeochemical reactions that occur during saline intrusion. In this study, we characterized flow and dispersive mixing in a confined sand aquifer subjected to saline intrusion, using both field observations and numerical modeling. Observations from an extensive monitoring network revealed a saline wedge extending approximately 500 m inland. We simulated density-dependent flow with MIN3P and used PEST++ to estimate dispersivity and diffusion from field observations. In effect, we use salinity data to measure the dispersivity through inverse modeling. The longitudinal and transverse dispersivity were calibrated at 0.1 m and 0.001 m, respectively, while the molecular diffusion coefficient was 1.2 × 10<sup>−9</sup> m<sup>2</sup>/s. Sensitivity analyses show that transverse dispersivity affects mixing-zone characteristics more than longitudinal dispersivity. Our results highlight the importance of accurately estimating dispersivity values to model the width of the mixing zone, which strongly controls geochemical reactions at the site. These findings provide insights into the processes driving freshwater–saline water mixing in coastal aquifers and offer guidance for future modeling studies on geochemical dynamics during saline intrusion.</div></div>","PeriodicalId":15530,"journal":{"name":"Journal of contaminant hydrology","volume":"277 ","pages":"Article 104816"},"PeriodicalIF":4.4,"publicationDate":"2025-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145788229","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}

引用次数: 0

Aggregation kinetics and stability of Ce(IV)-borate colloid: Effect of pH, electrolytes, gibbsite colloid, and humic acid colloid Ce(IV)-硼酸胶体的聚集动力学和稳定性：pH、电解质、三水铝石胶体和腐殖酸胶体的影响

IF 4.4 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-12-15 DOI: 10.1016/j.jconhyd.2025.104811

Kang Chen , Rui Zhang , Chunsheng Shi , Shanrong Yuan , Zishuo Li , Daming Zhang , Qiang Jin , Zhijun Guo , Zongyuan Chen

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 > KCl > MgCl₂ > NaNO₃ > CaCl₂ > 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.

四价锕系元素（An(IV)）可以从高放废物（HLW）玻璃中以An(IV)-硼酸盐固有胶体的形式释放。本研究选择Ce（IV）作为An（IV）的类似物，通过聚集动力学实验研究Ce(IV)-硼酸盐胶体的稳定性随pH、电解质、三水石胶体和腐殖酸（HA）胶体的变化规律。测定了Ce(IV)-硼酸酯胶体的等电点（pHIEP）为7.8，随着pH值的接近，胶体的聚集性逐渐增强。临界混凝浓度（CCC）顺序为NaCl >； KCl > MgCl2 > NaNO3 > CaCl2 > Na2SO4。带正电的三水铝石胶体由于静电斥力增强而抑制了Ce(IV)-硼酸钙胶体的聚集。相反，带负电荷的HA对Ce(IV)-硼酸酯胶体稳定性的影响依赖于HA浓度。低浓度的HA （0.1 ~ 1.0 mg/L）降低了Ce(IV)-硼酸酯胶体的表面电荷，导致CCC降低，而高浓度的HA （2.5 ~ 25 mg/L）增强了Ce(IV)-硼酸酯颗粒的胶体稳定性。计算得到Ce(IV)-硼酸盐胶体的Hamaker常数为1.29 × 10−20 j，用Derjaguin-Landau-Verwey-Overbeek （DLVO）理论及其变体计算得到的相互作用能可以很好地描述胶体稳定性的变化。这些结果提供了对Ce(IV)-硼酸盐胶体性质的全面理解，并为评估An（IV）在真实地下环境中的命运和运移提供了有价值的见解。

{"title":"Aggregation kinetics and stability of Ce(IV)-borate colloid: Effect of pH, electrolytes, gibbsite colloid, and humic acid colloid","authors":"Kang Chen , Rui Zhang , Chunsheng Shi , Shanrong Yuan , Zishuo Li , Daming Zhang , Qiang Jin , Zhijun Guo , 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<sub>IEP</sub>) 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 > KCl > MgCl<sub>2</sub> > NaNO<sub>3</sub> > CaCl<sub>2</sub> > Na<sub>2</sub>SO<sub>4</sub>. 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<sup>−20</sup> 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":"2025-12-15","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}

引用次数: 0