Journal of contaminant hydrology最新文献_第6页

High-performance polymeric aluminum ferric sulfate from Baihe pyrite slag: Enhanced coagulation in soil leaching alkaline wastewater and mechanistic insights 白河黄铁矿渣制备高性能聚合硫酸铝铁：增强土壤浸出碱性废水的混凝作用及机理研究。

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

Journal of contaminant hydrology

Pub Date : 2025-12-31 DOI: 10.1016/j.jconhyd.2025.104839

Aifang Pan , Runyong Ma , Jianwu Zhang , Dahong Chen , Longyue Li , Yao Ke

Efficient removal of inorganic suspended matter is crucial for the recovery of soil leaching alkaline wastewater. This study aimed to develop a high-alumina inorganic polymer coagulant, polymerized aluminum ferric sulfate (PAFS), specifically targeting inorganic suspended matter in alkaline soil leaching wastewater. PAFS was prepared from aluminum ferric sulfate (Al_0.862Fe_0.138(SO₄)₃·nH₂O) synthesized from Baihe pyrite slag, enabling resource utilization of this industrial waste. The physicochemical properties of the slag, intermediate sulfate, and final PAFS were characterized by XRD, SEM, and FT-IR. The optimal synthesis conditions were pH 3.0, aging temperature 80 °C, aging time 75 min, and combined AlFe content 11 %. The coagulation mechanism was systematically investigated, revealing a three-stage pH-dependent synergy of “charge neutralization - adsorption bridging - precipitation”: (1) At pH 1.0–2.0, low-polymerization PAFS destabilizes colloids via charge neutralization; (2) At the optimal pH 3.0, enhanced hydrolysis produces multi-nuclear hydroxo-complexes ([Fe₂(OH)₂]⁴⁺ and [Al₁₃O₄(OH)₂₄]⁷⁺) that efficiently bridge particles into dense, settleable flocs through hydroxo bridging and sweep flocculation; (3) The sulfate-linked FeAl copolymer structure imparts superior alkali resistance, while over-hydrolysis at pH > 3.0 causes precipitation and efficiency loss. In simulated wastewater treatment, PAFS achieved a 99.9 % turbidity removal rate under alkaline conditions (pH 8.0–11.0). This work provides an efficient, low-cost solution for alkaline soil leaching wastewater by converting pyrite slag into a high-performance coagulant, offering notable economic and environmental benefits.

无机悬浮物的高效去除是土壤浸出碱性废水回收的关键。本研究旨在针对碱性土壤浸出废水中的无机悬浮物，研制高铝无机高分子混凝剂聚合硫酸铝铁（PAFS）。以白河黄铁矿渣为原料合成硫酸铁铝（Al0.862Fe0.138(SO4)3·nH2O）制备PAFS，实现了该工业废渣的资源化利用。采用XRD、SEM和FT-IR对渣、中间硫酸盐和最终PAFS的理化性质进行了表征。最佳合成条件为pH 3.0，时效温度80℃，时效时间75 min，复合AlFe含量11%。系统研究了混凝机理，揭示了“电荷中和-吸附桥接-沉淀”的三个阶段的pH依赖协同作用：(1)在pH 1.0-2.0时，低聚合PAFS通过电荷中和使胶体不稳定；(2)在最佳pH为3.0时，强化水解产生多核羟基配合物([Fe2(OH)2]4+和[Al13O4(OH)24]7+)，通过羟基桥接和扫絮凝有效地将颗粒桥接成致密、可沉降的絮凝体；(3)硫酸盐连接FeAl共聚物结构具有较好的耐碱性，而pH > 3.0下的过水解会导致沉淀和效率损失。在模拟废水处理中，paafs在碱性条件下（pH 8.0-11.0）的浊度去除率达到99.9%。本研究通过将黄铁矿渣转化为高性能混凝剂，为碱土浸出废水提供了一种高效、低成本的解决方案，具有显著的经济效益和环境效益。

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引用次数: 0

Groundwater quality prediction using novel hybrid classification and regression models 基于新型混合分类与回归模型的地下水水质预测。

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

Journal of contaminant hydrology

Pub Date : 2025-12-29 DOI: 10.1016/j.jconhyd.2025.104834

Mouigni Baraka Nafouanti , Junxia Li , Usman Sunusi Usman , Grant Charles Mwakipunda , Etsu Binta Fatima , Abdullah Sani Baba

Groundwater quality degradation is a significant challenge in the North China Plain (NCP), where groundwater is the primary source of water. Traditional methods for assessing groundwater quality, such as laboratory and hydraulic analyses, are costly and time-consuming. This study applies novel hybrid models for classification and regression analysis, including Stacking Classifiers (XGBoost, LightGBM), Hybrid LightGBM with Particle Swarm Optimization (LightGBM-PSO), Genetic Algorithm with Random Forest (GA-RF), and Genetic Algorithm with LightGBM (GA-LightGBM) to predict groundwater quality in Cangzhou. A total of 460 groundwater chemistry samples were collected to assess the quality of groundwater. The results of the hydrochemistry revealed that the dominant ions are HCO₃⁻, Cl⁻, Ca²⁺, and SO₄²⁻. The primary water types identified were Na-HCO₃, NaCl, Ca-HCO₃, and Ca-Na-HCO₃, indicating the significant impact of water-rock interactions, evaporation, and salinization. For the prediction of groundwater quality, the hybrid models LightGBM-PSO and GA-RF demonstrated the highest accuracy, achieving 93 %, 95 %, and 99 % accuracy for Classes 0, 1, and 2, respectively. The GA-RF model showed strong predictive performance with an R² of 0.99, RMSE of 0.01, and MAE of 0.02. The SHAP analysis identified key features influencing groundwater quality, including Na⁺, HCO₃⁻, F⁻, Cl⁻, Ca²⁺, SO₄²⁻, Mg²⁺, TDS, and EC. The Water Quality Index (WQI) classified 60.28 % of the samples as excellent or good, while 40 % were categorized as poor or very poor. These findings highlight the effectiveness of hybrid models in predicting groundwater quality and offer valuable insights for groundwater resource management, not only in Cangzhou but globally.

地下水水质退化是华北平原地区面临的一个重大挑战，地下水是该地区主要的水源。评估地下水质量的传统方法，如实验室和水力分析，既昂贵又耗时。本研究将叠层分类器（XGBoost、LightGBM）、混合LightGBM与粒子群优化（LightGBM- pso）、随机森林遗传算法（GA-RF）和LightGBM遗传算法（GA-LightGBM）等新型混合模型应用于沧州市地下水水质预测。共采集了460份地下水化学样品，对地下水水质进行了评价。水化学结果表明，主要离子为HCO3-、Cl-、Ca2+和SO42-。发现的主要水类型为Na-HCO3、NaCl、Ca-HCO3和Ca-Na-HCO3，表明水岩相互作用、蒸发和盐渍化的影响显著。对于地下水水质的预测，混合模型LightGBM-PSO和GA-RF的预测精度最高，在0、1和2级的预测精度分别达到93%、95%和99%。GA-RF模型具有较强的预测能力，R2为0.99，RMSE为0.01，MAE为0.02。SHAP分析确定了影响地下水质量的关键特征，包括Na+、HCO3-、F-、Cl-、Ca2+、SO42-、Mg2+、TDS和EC。水质指数（WQI）将60.28%的样本分类为优秀或良好，而40%的样本分类为差或极差。这些发现突出了混合模型在预测地下水质量方面的有效性，并为沧州乃至全球地下水资源管理提供了有价值的见解。

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引用次数: 0

Performance and longevity of colloidal silica gel in blocking vertical water flow and contaminant transport in the annuli of long-screened wells: Laboratory and numerical evaluation 胶体硅胶在长筛井环空阻断垂直水流和污染物输送中的性能和寿命：实验室和数值评估

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

Journal of contaminant hydrology

Pub Date : 2025-12-29 DOI: 10.1016/j.jconhyd.2025.104837

Lirong Zhong, Jonah A. Bartrand, Katherine A. Muller, Rob D. Mackley, Jonathan N. Thomle, Zoe G. Vincent

This laboratory-based study evaluated the performance and long-term (months) stability of colloidal silica (CS) gels in blocking vertical water flow and controlling chemical transport in subsurface applications, especially in the well annuli of long-screened wells. Laboratory-scale rheological tests demonstrated the injectivity of CS suspensions in expected field applications. Laboratory column, sandbox experiments and numerical modeling were used to assess the efficacy of CS gel in reducing hydraulic conductivities of the well annulus system. Further, a contaminant diffusion test was applied to evaluate the performance of CS gel-sand pack in mitigating transport of contamination. Rheological analyses highlighted the shear-thinning behavior of modified CS suspensions, facilitating more efficient injections in field applications. Hydraulic conductivity (K) tests revealed notable K reductions following CS gel injection, confirming its effectiveness in blocking vertical water flow. Diffusion tests demonstrated that no hexavalent chromium (Cr(VI)) migrated through CS gel-grouted sand barriers in 6 months, suggesting their strong potential as containment solutions for hazardous contaminants. Numerical simulations validated experimental data to reinforce the performance assessment of CS gels as barriers. The findings underscore CS gel's promising applications not only in long-screened well annular systems, but also in subsurface remediation, groundwater protection, and contaminant containment, providing critical insights for field-scale implementations.

这项实验室研究评估了胶体硅（CS）凝胶在地下应用中阻断垂直水流和控制化学物质输送的性能和长期稳定性，特别是在长筛井的井环空中。实验室规模的流变试验证明了CS悬浮液在预期的现场应用中的注入性。通过实验室柱、沙盒实验和数值模拟来评估CS凝胶降低井环空系统水力导度的效果。此外，采用污染物扩散试验来评估CS凝胶-砂充填在减少污染物运移方面的性能。流变学分析强调了改性CS悬浮液的剪切减薄行为，有助于在现场应用中更有效地注入。水导率(K)测试显示，CS凝胶注入后K值显著降低，证实了其阻断垂直水流的有效性。扩散试验表明，6个月内没有六价铬（Cr(VI)）通过CS凝胶注浆砂屏障迁移，这表明它们作为有害污染物的密封解决方案具有强大的潜力。数值模拟验证了实验数据，加强了CS凝胶作为屏障的性能评价。这一发现强调了CS凝胶不仅在长筛井环空系统中具有广阔的应用前景，而且在地下修复、地下水保护和污染物控制方面也具有重要的应用前景，为现场大规模实施提供了重要的见解。

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引用次数: 0

Deciphering the spatiotemporal dynamics and source characteristics of nutrients under anthropogenic pressure in Taipu River, China 太浦江人为压力下养分时空动态及来源特征解读

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

Journal of contaminant hydrology

Pub Date : 2025-12-29 DOI: 10.1016/j.jconhyd.2025.104835

Tong Wang , Jiayi Kou , Fengjunxi Chen , Yalong Li , Yaojen Tu , Yanping Duan

Surface water quality dynamics is a pivotal factor in sustainable water management. As a strategic waterway in Taihu Lake Basin (China), Taipu River plays a key role in integrating water management through flood control, water supply, and ecological preservation across Jiangsu, Zhejiang, and Shanghai. However, under evolving anthropogenic pressures, systematic studies characterizing its nutrient spatiotemporal variations and pollution drivers remain limited. In this study, the spatiotemporal (October 2020–July 2021 from upstream to downstream) distributions and source characteristics of key nutrients from Taipu River were evaluated through various water quality index methods, coupled with multi-approach source apportionment (principal component analysis and positive matrix factorization). Results indicated that the concentrations of total nitrogen (TN) and chemical oxygen demand (COD) in Taipu River gradually increased from upstream (TN: 0.9–1.2 mg L⁻¹, COD: 11.5–15.2 mg L⁻¹) to downstream (TN: 1.1–1.9 mg L⁻¹, COD:11.0–21.7 mg L⁻¹), and exceeded regulatory Class III limits in summer/winter (>1.0 mg L⁻¹) and spring/autumn (>20 mg L⁻¹), respectively. The increased TN likely resulted from nitrogen fertilizer loss due to rainfall, whereas the increase in COD is probably linked to the release of metabolic products from algae. Water contamination analyses identified a slightly-contaminated T7 site (i.e., TN = 1.51 ± 0.71 mg L⁻¹, COD = 34 ± 9.0 mg L⁻¹, exceeding Class IV), with primary contamination sources attributed to industrial activity (e.g., textile industry). For this T7 site with slight water contamination, the in-situ remediation strategies such as adding synthetic microbiomes, incorporating aquatic plants, and engineering intervention for nitrogen and COD pollution are recommended. These findings highlight the urgent requirement for targeted measures to mitigate nitrogen/COD loads, which is crucial to improve water quality and ecosystem health of the Taihu Lake Basin.

地表水质量动态是可持续水管理的关键因素。太浦江作为中国太湖流域的战略航道，在江浙沪地区的防洪、供水和生态保护等水资源管理一体化中发挥着关键作用。然而，在不断变化的人为压力下，对其养分时空变化特征和污染驱动因素的系统研究仍然有限。本研究通过多种水质指标方法，结合多方法来源解析（主成分分析和正矩阵分解），评价了太浦江主要营养物质的时空（2020年10月- 2021年7月，由上至下）分布和来源特征。结果表明：太浦江总氮（TN）和化学需氧量（COD）浓度由上游（TN: 0.9 ~ 1.2 mg L−1,COD: 11.5 ~ 15.2 mg L−1）向下游（TN: 1.1 ~ 1.9 mg L−1,COD:11.0 ~ 21.7 mg L−1）逐渐升高，并分别在夏/冬（>1.0 mg L−1）和春/秋（>20 mg L−1）超过III类标准。全氮的增加可能是由于降雨造成氮肥损失，而COD的增加可能与藻类代谢产物的释放有关。水污染分析确定了一个轻度污染的T7站点（即TN = 1.51±0.71 mg L−1,COD = 34±9.0 mg L−1，超过IV级），主要污染源归因于工业活动（如纺织工业）。对于该T7轻度水污染场地，建议采用添加合成微生物组、引入水生植物、工程干预氮和COD污染等原位修复策略。这些研究结果表明，迫切需要采取有针对性的措施减轻氮/COD负荷，这对改善太湖流域水质和生态系统健康至关重要。

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引用次数: 0

Seasonal behavior of iodine-129 in a contaminated wetland: A field-scale conceptual site model from the Savannah River Site 受污染湿地中碘-129的季节性行为：来自萨凡纳河遗址的现场尺度概念场地模型。

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

Journal of contaminant hydrology

Pub Date : 2025-12-29 DOI: 10.1016/j.jconhyd.2025.104836

Hansell Gonzalez-Raymat , Miles E. Denham , Haruko M. Wainwright , Holly H. VerMeulen , Nathaniel A. Losey , Jeffrey Thibault , Kevin Boerstler , Austin Coleman , Jordan Floyd , Brady D. Lee , Ravi Gudavalli , Carol A. Eddy-Dilek

Wetlands are dynamic ecosystems that can immobilize contaminants for extended periods but can also release them when hydrological and/or biogeochemical conditions change. Although this behavior is well recognized, the field-scale processes controlling the retention and release of certain contaminants such as iodine-129 (¹²⁹I) remain poorly understood, particularly in a contaminated wetland at the U.S. Department of Energy's Savannah River Site. In this study, we hypothesized that seasonal variations in groundwater flux regulate ¹²⁹I behavior by altering the biogeochemistry of the wetland seeps and underlying sediments. To test this hypothesis, we combined soil and water sampling, microbial analysis, iodine speciation, and autonomous sensor monitoring. Our results show that ¹²⁹I is preferentially retained in the organic-rich surface soil, with concentrations peaking at 0.22 Bq g⁻¹ within the upper 0.15 m followed by a decrease with depth. Pronounced seasonal fluctuations in ¹²⁹I concentrations were observed in surface water, increasing from 0.9–2 Bq L⁻¹ in winter to 3–8 Bq L⁻¹ in summer, while groundwater concentrations remained consistently lower (0.2–0.6 Bq L⁻¹) and exhibited minimal seasonal variability. These variations correspond to seasonal changes in groundwater flux towards the seeps: higher flux during winter flushes the seeps causing ¹²⁹I concentrations in surface water to be close to groundwater concentrations, while reduced flux during summer promotes stagnant and anoxic conditions that facilitate the release of bound ¹²⁹I from the organic-rich soil into surface water. Iodine speciation analysis indicates that 78 to 99 % of total iodine in surface water existed as organoiodine, suggesting organic matter degradation drives ¹²⁹I remobilization. These observations were integrated into a field-scale conceptual site model, linking hydrological and biogeochemical processes to the retention and release of ¹²⁹I occurring in the wetlands.

湿地是动态的生态系统，可以长时间固定污染物，但也可以在水文和/或生物地球化学条件发生变化时释放污染物。虽然这种行为已经得到了很好的认识，但控制某些污染物（如碘-129 (129I)）的保留和释放的现场尺度过程仍然知之甚少，特别是在美国能源部萨凡纳河遗址的受污染湿地中。在本研究中，我们假设地下水通量的季节变化通过改变湿地渗漏物和下垫沉积物的生物地球化学来调节129I行为。为了验证这一假设，我们结合了土壤和水采样、微生物分析、碘物种形成和自主传感器监测。结果表明，129I在富有机质的表层土壤中优先保留，浓度在0.15 m以上达到峰值0.22 Bq g-1，随后随深度降低。地表水129I浓度季节性波动明显，冬季为0.9 ~ 2 Bq L-1，夏季为3 ~ 8 Bq L-1，而地下水浓度持续较低（0.2 ~ 0.6 Bq L-1），季节性变化最小。这些变化与地下水流向渗漏层的季节性变化相对应：冬季较高的通量冲刷渗漏层，使地表水中的129I浓度接近地下水浓度，而夏季通量的减少促进了停滞和缺氧条件，促进了结合的129I从富有机质土壤释放到地表水中。碘形态分析表明，地表水中总碘的78 ~ 99%以有机碘的形式存在，表明有机物降解驱动了129I的再活化。这些观测结果被整合到一个野外尺度的概念场地模型中，将水文和生物地球化学过程与湿地中发生的129I的保留和释放联系起来。

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引用次数: 0

Characteristics of tetracycline adsorption by different embedded biochar materials 不同生物炭包埋材料对四环素的吸附特性

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

Journal of contaminant hydrology

Pub Date : 2025-12-29 DOI: 10.1016/j.jconhyd.2025.104833

Chunming Wang, Anqi Zhao , Meng Qi, Yi Jiang

This study explored six novel biochar composite materials for adsorbing tetracycline antibiotics adsorption. These materials—namely, Bauhinia biochar, Bauhinia magnetic biochar, rice straw biochar, rice straw magnetic biochar, rice straw hydrothermal biochar, and rice straw hydrothermal magnetic biochar, were encapsulated with sodium alginate to form adsorption spheres. Results showed that magnetic biochar materials had higher adsorption capacities than non-magnetic ones, with rice straw magnetic biochar adsorption spheres showing the highest capacity at 3 mg/g. The isothermal adsorption of tetracycline by rice straw magnetic biochar adsorption spheres followed the Freundlich model, while the adsorption kinetics were best described by the pseudo-second-order model. The adsorption half-life was 3 h, and factors including biochar dosage, temperature, pH, and salinity affected the removal rate. SEM and FTIR analyses of rice straw hydrothermal magnetic biochar, rice straw magnetic biochar, and rice straw biochar revealed that rice straw biochar materials had a microporous structure mainly composed of C and O, while magnetic materials also contained significant amounts of iron. All three materials contained hydroxyl, alkene, alkyne, and alkyl functional groups. The increased FeO bonds in magnetic materials were the primary reason for the enhanced adsorption performance. Moreover, rice straw magnetic biochar adsorption spheres showed good reusability for high-concentration tetracycline. For low-concentration tetracycline, the adsorption capacity recovery exceeded 60 %, achieving an overall removal rate of over 80 %. Owing to their excellent recyclability and rapid adsorption rates, the rice straw magnetic biochar adsorption spheres hold significant potential in advanced wastewater treatment containing tetracycline antibiotics.

本研究探索了六种新型吸附四环素类抗生素的生物炭复合材料。将紫荆花生物炭、紫荆花磁性生物炭、稻秆生物炭、稻秆磁性生物炭、稻秆水热生物炭、稻秆水热磁性生物炭等材料包被海藻酸钠形成吸附球。结果表明，磁性生物炭材料的吸附能力高于非磁性材料，其中稻草磁性生物炭吸附球在3 mg/g时的吸附能力最高。稻秆磁性生物炭吸附球对四环素的等温吸附符合Freundlich模型，而吸附动力学最适合用拟二阶模型描述。吸附半衰期为3 h，生物炭投加量、温度、pH、盐度等因素影响去除率。对秸秆水热磁性生物炭、秸秆磁性生物炭和秸秆生物炭的SEM和FTIR分析表明，秸秆生物炭材料具有以C和O为主的微孔结构，磁性材料中还含有大量的铁。这三种材料都含有羟基、烯烃、炔和烷基官能团。磁性材料中FeO键的增加是吸附性能增强的主要原因。此外，秸秆磁性生物炭吸附球对高浓度四环素具有良好的可重复使用性。对于低浓度四环素，吸附容量回收率超过60%，总体去除率达到80%以上。稻秆磁性生物炭吸附球具有良好的可回收性和快速的吸附速率，在含四环素类抗生素废水的深度处理中具有很大的潜力。

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引用次数: 0

Quantitative profile, sources and health implications of polychlorinated biphenyls (PCBs) in the strategic Otin River water, Nigeria 尼日利亚战略奥廷河水中多氯联苯的数量概况、来源和健康影响。

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

Journal of contaminant hydrology

Pub Date : 2025-12-26 DOI: 10.1016/j.jconhyd.2025.104826

Adebanjo Jacob Anifowose, Mariam Abolore Muritala, Aaliyah Omotayo Bello, Abosede Susannah Oguntolu, Kazeem Abiodun Ibrahim, Shola Hezekiah Awojide

Otin River is one of the longest strategic rivers in Osun State (Nigeria) with diverse economic values: commercial fishing, community water supply, farming and domestic activities. Nineteen toxic polychlorinated biphenyls (PCBs) were studied in the river water to understand their contamination levels, sources and potential health threats to humans. The river water samples were collected from six locations. The PCBs were extracted by liquid-liquid extraction and quantified using a gas chromatograph-mass spectrometer (GC–MS). All the PCBs were detected in the river water, ranging from 0.002 μg/L (PCB206) to 0.96 μg/L (PCB180). Using the average concentration of the individual PCB measured, their total concentration was 2.96 μg/L, which exceeded the standard permissible limit of 0.5 μg/L for drinking water. This indicated a high level of contamination. The six dominant congeners in the river water were in the following order: PCB180 > PCB170 > PCB44 > PCB5 > PCB187 > PCB18 (0.12 μg/L). The total PCB concentration at the river midstream housing the Eko-Ende Dam was significantly higher (P < 0.05) than that measured at the upstream and downstream. Using principal component analysis, the PCB sources were profiled as the dam's hydraulic system, plastics, paints and farm's agrochemical runoffs. Of the 19 PCBs, PCB5, PCB44, PCB170 and PCB180 posed both non-carcinogenic and carcinogenic risks to human health. PCB170 and PCB180 posed the highest risks via ingestion. Some residents/farmers usually consume the water. Thus, the PCB concentrations could cause unimaginable health risks to the people and aquatic life, necessitating effective management strategies.

奥廷河是奥孙州（尼日利亚）最长的战略河流之一，具有多种经济价值：商业捕鱼、社区供水、农业和家庭活动。对河水中的19种有毒多氯联苯进行了研究，以了解它们的污染水平、来源和对人类的潜在健康威胁。河水样本是从六个地点采集的。采用液液萃取法提取多氯联苯，气相色谱-质谱联用仪（GC-MS）定量。河水中检测到的多氯联苯含量在0.002 μg/L (PCB206) ~ 0.96 μg/L （PCB180）之间。按测得的单个多氯联苯平均浓度计算，其总浓度为2.96 μg/L，超过了饮用水标准允许浓度0.5 μg/L。这表明污染程度很高。6个优势同系物在河水中的分布顺序为：PCB180 > PCB170 > PCB44 > PCB5 > PCB187 > PCB18 （0.12 μg/L）。Eko-Ende大坝所在的中游多氯联苯总浓度显著升高(P

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引用次数: 0

Characterizing seawater intrusion and groundwater vulnerability to salinization along the east coast of India 印度东海岸海水入侵和地下水易受盐碱化影响的特征。

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

Journal of contaminant hydrology

Pub Date : 2025-12-26 DOI: 10.1016/j.jconhyd.2025.104829

Biplab Sarkar , Aznarul Islam , Amit Kumar , Swapan Talukdar , Md Nawaj Sarif , Akanksha Pandey , Kaustubh Lahiri , Sutapa Mukherjee , Abdur Rahman , SK. Mafizul Haque , Abujar Rahaman

The groundwater resource in the coastal aquifers is highly vulnerable to seawater intrusion and salinization, triggered by multiple physical and anthropogenic factors. Therefore, the present study aims to address this pressing issue in the eastern coastal region of India based on 10 hydrochemical parameters of 1228 groundwater samples coupled with 15 lithologs, and annual groundwater draft for irrigation, industry, and domestic data for 37 coastal districts of the study area. The results reveal that 39.09 % of the samples are recorded as saline by the hydrochemical facies evolution diagram, while 55.09 % of the samples exhibit SMI >1, indicating the widespread presence of seawater intrusion into coastal aquifers. The region-specific study of SMI reveals that 91 out of 134 samples (67.91 %) are identified as SMI > 1 in West Bengal while the corresponding proportions are 63.61 % for Tamil Nadu, 56.10 % for Andhra Pradesh, and 32.49 % for Odisha. The study has also revealed hotspots for SMI, and the coastal regions of Odisha, Andhra Pradesh, and Tamil Nadu are found with significant hotspots for groundwater salinization. The fine sand and silt layers of the aquifers play a conducive role for the presence of saline water through direct seepage from the sea. Moreover, the excessive groundwater draft (0–7.94 × 10⁸ m³) for irrigation, (0–1.878 × 10⁷ m³) for industrial, and (0–2.029 × 10⁸ m³) for domestic uses shifts the hydraulic gradient landward, leading to the movement of saline water to the coastal aquifers.

沿海含水层地下水资源极易受到海水入侵和盐渍化的影响，受到多种物理和人为因素的影响。因此，本研究旨在根据研究区37个沿海地区1228个地下水样品的10个水化学参数以及15个岩性，以及灌溉、工业和生活用水的年地下水用量数据，解决印度东部沿海地区这一紧迫问题。结果表明，39.09%的样品水化学相演化图记录为咸化，55.09%的样品显示SMI >1，表明海水侵入沿海含水层的现象普遍存在。SMI的区域特异性研究显示，西孟加拉邦134个样本中有91个（67.91%）被确定为SMI >1，而泰米尔纳德邦的相应比例为63.61%，安得拉邦为56.10%，奥里萨邦为32.49%。该研究还揭示了SMI的热点地区，奥里萨邦、安得拉邦和泰米尔纳德邦的沿海地区被发现具有地下水盐渍化的显著热点。含水层的细沙和粉砂层对海水直接渗透的咸水起到了有利的作用。此外，过量的灌溉地下水（0-7.94 × 108 m3）、工业地下水（0-1.878 × 107 m3）和生活地下水（0-2.029 × 108 m3）使水力梯度向陆地移动，导致咸水向沿海含水层移动。

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引用次数: 0

Development and application evaluation of baseflow separation/pollution load estimation tool considering the characteristics of the recession by flow condition-specific 考虑特定流态衰退特性的基流分离/污染负荷估算工具的开发与应用评价。

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

Journal of contaminant hydrology

Pub Date : 2025-12-26 DOI: 10.1016/j.jconhyd.2025.104832

Yeonji Jeong , Jeongho Han , Seoro Lee , Sangjoon Bak , Gwanjae Lee , Jonggun Kim , Kyoung Jae Lim

This study introduces the WAPLE4 system, developed to accurately separate direct runoff and baseflow and calculate pollution loads while considering the recession characteristics of hydrographs under varying flow condition-specific. The system was applied to four major watersheds in South Korea, demonstrating improved accuracy in baseflow separation, with an average baseflow reduction of 7 % when the β parameter by flow condition-specific was applied. Furthermore, pollution load analysis revealed reductions in TP and TN loads by 10.92 % and 10.56 %, underscoring the effectiveness of this parameter in refining pollution load estimates. These findings highlight the system's ability to improve flow condition-specific baseflow and pollutant load calculations while reflecting the distinct characteristics of individual watersheds. By enabling precise quantification of pollutant loads from both direct runoff and baseflow, this system can be effectively utilized to provide foundational data for the development of more comprehensive watershed management strategies and aid decision-makers in addressing water quality challenges more effectively.

本研究引入了WAPLE4系统，该系统能够准确地分离直接径流和基流，并计算污染负荷，同时考虑了不同流量条件下水文曲线的衰退特征。该系统应用于韩国的四个主要流域，显示了基流分离的准确性，当应用特定流量条件的β参数时，平均基流减少了7%。此外，污染负荷分析显示，总磷和总氮负荷分别减少了10.92%和10.56%，强调了该参数在改进污染负荷估算中的有效性。这些发现突出了该系统在反映单个流域的独特特征的同时，能够改善特定流量条件的基流和污染物负荷计算。通过对直接径流和基流的污染物负荷进行精确量化，该系统可以有效地为制定更全面的流域管理战略提供基础数据，并帮助决策者更有效地应对水质挑战。

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引用次数: 0

Characteristics of polycyclic aromatic hydrocarbons along an urban river in snowmelt and non-snowmelt periods from Northeast China 东北城市河流融雪期和非融雪期多环芳烃特征

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

Journal of contaminant hydrology

Pub Date : 2025-12-24 DOI: 10.1016/j.jconhyd.2025.104828

TeRi GeLe , Kaijun Lu , Zucheng Wang , Shasha Liu , Ziping Liu

The polycyclic aromatic hydrocarbons (PAH) concentrations along an urban river from Northeast China were investigated during snowmelt and non-snowmelt periods. The results showed that the concentration of dissolved PAHs in the samples collected during the snowmelt period ranged from 61 to 271 ng L⁻¹, significantly lower than those in the non-snowmelt period, which ranged from 141 to 833 ng L⁻¹ (p < 0.05). The highest PAH concentrations in river were generally observed at municipal sewage treatment outlet. PAH concentrations were positively correlated with SUVA₂₅₄ value (p < 0.01) and negatively correlated with dissolved organic carbon (DOC), total nitrogen (TN), and total phosphorus (TP) (p < 0.01). PAH concentration increased from the upstream suburbs to urban areas, and downstream suburbs in snowmelt period, whereas an opposite trend was observed during non-snowmelt periods. These findings indicate that different factors control PAH concentration distribution along the urban river during two periods. However, despite the spatial distribution pattern of PAHs along the upstream-downstream gradient changing due to snowmelt, the overall PAH levels during snowmelt were not higher than those observed in the non-snowmelt period. This study implies that snowmelt may not always rapidly increase PAH concentrations in aquatic environment, especially in urban rivers.

对东北某城市河流在融雪期和非融雪期的多环芳烃（PAH）浓度进行了研究。结果表明：融雪期样品中溶解多环芳烃的浓度为61 ~ 271 ng L-1，显著低于非融雪期样品的141 ~ 833 ng L-1 （p 254值）

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引用次数: 0