Journal of contaminant hydrology最新文献_第3页

Magnetic biochar prepared by co-pyrolysis of sludge and organic medical solid waste for pH-universal removal of ciprofloxacin 污泥与有机医疗固体废物共热解制备磁性生物炭用于pH-universal脱除环丙沙星

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

Journal of contaminant hydrology

Pub Date : 2026-01-20 DOI: 10.1016/j.jconhyd.2026.104862

Junping Meng , Binbin Yao , Jinsheng Liang , Xinhui Duan , Xiangying Wei

In this study, sludge biochar was prepared via the co-pyrolysis method using the compatibility of sewage sludge (SS) in different seasons with organic medical solid waste (OMSW) and activated by alkali conditions for the removal of ciprofloxacin (CIP) in water with different pH values. The maximum adsorption capacity of the two biochars (KS1MBC and KS2MBC) reached 83.49 mg/g and 86.19 mg/g, respectively. The structure of the biochars was characterized via XRD, BET and SEM, and the adsorption mechanism of the biochars was investigated by FTIR, Raman, and XPS. The adsorption processes of the modified biochar followed pseudo-second-order kinetics and the Langmuir isothermal adsorption model, were dominated by chemical adsorption and monolayer adsorption, and were controlled by both liquid film diffusion and intraparticle diffusion. The adsorption mechanisms included pore adsorption, electrostatic attraction, π-π interactions, hydrogen bonding, and surface complexation. After hydrothermal activation by KOH, the surface of the biochar was etched by alkali to produce a nanothin lamellar structure, which increased the specific surface area to more than 200 m²/g in both cases, thus greatly enhancing the adsorption performance of the biochar. Moreover, due to the iron-containing properties of the sludge, it can be recycled through magnetic separation, thereby reducing treatment costs and enhancing the material's overall sustainability. The alkali-modified biochar demonstrates significant potential for application in antibiotic contamination remediation and provides a theoretical foundation for advancing waste treatment and promoting green environmental protection.

本研究利用不同季节污水污泥（SS）与有机医疗固体废物（OMSW）的相容性，采用共热解法制备污泥生物炭，并在碱条件下活化，在不同pH值的水中去除环丙沙星（CIP）。两种生物炭（KS1MBC和KS2MBC）的最大吸附量分别为83.49 mg/g和86.19 mg/g。通过XRD、BET、SEM等表征了生物炭的结构，并通过FTIR、Raman、XPS等研究了生物炭的吸附机理。改性生物炭的吸附过程遵循拟二级动力学和Langmuir等温吸附模型，以化学吸附和单层吸附为主，同时受液膜扩散和颗粒内扩散控制。吸附机理包括孔吸附、静电吸引、π-π相互作用、氢键和表面络合。经KOH水热活化后，生物炭表面被碱蚀刻形成纳米薄层状结构，两种情况下的比表面积均大于200m2 /g，从而大大提高了生物炭的吸附性能。此外，由于污泥的含铁特性，它可以通过磁分离回收，从而降低处理成本，提高材料的整体可持续性。碱改性生物炭在抗生素污染修复中具有重要的应用潜力，为推进废物处理和促进绿色环保提供了理论基础。

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引用次数: 0

Targeting critical zones: A review of heterogeneity identification methods and driving mechanisms of watershed phosphorus transport 针对关键区域：流域磷转运异质性识别方法及驱动机制综述

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

Journal of contaminant hydrology

Pub Date : 2026-01-19 DOI: 10.1016/j.jconhyd.2026.104857

Qingxuan Wu , Rang Wang , Jing Yang , Hao Wang , Simin Li , Xin Jin

Non-point source phosphorus (P) transport is characterized by pronounced heterogeneity manifested in spatial clustering, temporal intermittency, and structural coupling, which together pose critical challenges for watershed management. Based on a systematic synthesis of existing studies, this review proposes a three-dimensional identification framework of hotspots-hot moments-critical source areas (H-M-C) and refines it into the concept of high-risk heterogeneous core units to characterize functional units that are co-activated by multidimensional conditions at the event scale and dominate phosphorus flux outputs. Methodologically, we trace the evolution of approaches from threshold-based criteria, distributed modeling, stable isotopes and geochemical fingerprinting, to intelligent data-driven methods, highlighting their complementarities and limitations in dimensional coverage, mechanistic interpretation, and cross-scale applicability. Furthermore, we summarize the “activation-amplification-regulation-feedback” mechanism chain from four perspectives: hydrological disturbances, land-use practices, geomorphic regulation, and multi-source feedbacks. This review emphasizes the necessity of perceiving non-stationary processes, developing scale-adaptive identification granularity, and constructing strategy-oriented feedback loops, thereby providing a structural framework and methodological pathways to bridge the gap between mechanistic understanding of phosphorus transport and practical management responses.

非点源磷(P)输运具有明显的异质性，表现为空间聚类、时间间歇性和结构耦合，这对流域管理构成了重大挑战。本文在系统综合现有研究的基础上，提出了热点-热点时刻-关键源区（H-M-C）的三维识别框架，并将其细化为高风险异质性核心单元的概念，以表征在事件尺度上被多维条件共同激活并主导磷通量输出的功能单元。在方法上，我们追溯了从基于阈值的标准、分布式建模、稳定同位素和地球化学指纹到智能数据驱动方法的演变，强调了它们在维度覆盖、机制解释和跨尺度适用性方面的互补性和局限性。在此基础上，从水文扰动、土地利用实践、地貌调节和多源反馈四个方面总结了“激活-放大-调节-反馈”机制链。这篇综述强调了感知非平稳过程、开发规模自适应识别粒度和构建面向策略的反馈回路的必要性，从而提供了一个结构框架和方法途径，以弥合对磷运输的机制理解与实际管理响应之间的差距。

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引用次数: 0

Occurrence and transport of per- and polyfluoroalkyl substances (PFAS) within a coastal groundwater aquifer 沿海地下水含水层内全氟和多氟烷基物质（PFAS）的发生和迁移

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

Journal of contaminant hydrology

Pub Date : 2026-01-19 DOI: 10.1016/j.jconhyd.2026.104861

Oliver A.H. Jones , Alexander Brindle , Mikaela Sterjovski , Shadha Al-Mashari , Pacian Netherway , Phoebe Lewis , Jennifer Martin , Matthew Currell

Understanding the sources, fate, and transport of per- and polyfluoroalkyl substances (PFAS) in coastal aquifers is essential for assessing the risk to these systems. We investigated PFAS concentrations within the Quaternary Aquifer of the Mornington Peninsula, Australia. The goals were to identify the sources of any observed contamination and assess the risk to ecological receptors associated with surface water bodies that interact with the aquifer. Fifteen bores were sampled at various depths. Multiple PFAS were detected in eight bores at ng/L concentrations (maximum ∑₈PFAS = 78.8 ng/L), while seven bores contained no detectable PFAS. Notable compounds included legacy perfluoroalkyl acids, such as PFOA, PFOS, and PFHxS, as well as the fluorotelomers 6:2 FTS and 6:2 diPAP. Several potential sources were identified, including two local landfills, a wastewater treatment plant, and the use of recycled water for irrigation in local agriculture. The bores with the highest total PFAS concentrations were located near the identified sources, particularly the landfills. No clear source was apparent for several PFOS-contaminated bores. Concentrations of PFOS at six bores were just above the current ecological guideline values for 99% species protection (0.00023 μg/L) but below the value for 95% species protection (0.13 μg/L). The risk to aquatic ecological receptors from contaminant discharge from groundwater into local watercourses is considered low, due to relatively low PFAS concentrations and moderate groundwater velocities; however, the combined total risk from seasonal fluxes and surface water runoff, and other discharges could be higher. Further monitoring and risk assessment are therefore recommended.

了解沿海含水层中全氟烷基和多氟烷基物质（PFAS）的来源、命运和迁移对评估这些系统的风险至关重要。研究了澳大利亚莫宁顿半岛第四纪含水层中PFAS的浓度。目的是确定任何观察到的污染源，并评估与地表水体相互作用的含水层有关的生态受体的风险。在不同深度取样了15个钻孔。在ng/L浓度下，8个孔中检测到多种PFAS（最大∑8PFAS = 78.8 ng/L）， 7个孔中未检测到PFAS。值得注意的化合物包括传统的全氟烷基酸，如PFOA、PFOS和PFHxS，以及6:2 FTS和6:2 diPAP的氟端粒。确定了几个可能的来源，包括两个当地的垃圾填埋场、一个废水处理厂和使用循环水用于当地农业灌溉。PFAS总浓度最高的钻孔位于已确定的污染源附近，特别是垃圾填埋场附近。几个全氟辛烷磺酸污染的钻孔没有明确的来源。6个孔的全氟辛烷磺酸浓度略高于现行99%物种保护的生态指标值（0.00023 μg/L），但低于95%物种保护的生态指标值（0.13 μg/L）。由于PFAS浓度相对较低和地下水流速适中，从地下水排放到当地水道的污染物对水生生态受体的风险被认为很低；然而，季节通量和地表水径流以及其他排放的综合总风险可能更高。因此建议进一步进行监测和风险评估。

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引用次数: 0

Experimental and numerical investigation of colloid-facilitated strontium transport in fractured granite under different hydrogeochemical conditions 不同水文地球化学条件下胶态锶在裂隙花岗岩中运移的实验与数值研究。

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

Journal of contaminant hydrology

Pub Date : 2026-01-16 DOI: 10.1016/j.jconhyd.2026.104858

Funing Ma , Fangfei Cai , Lihong Zhang , Sida Jia

Accurate prediction of radionuclide transport in fractured crystalline rock is vital for the long-term safety of high-level radioactive waste (HLW) geological disposal. However, the specific threshold conditions determining whether bentonite colloids (BC) facilitate or inhibit radionuclide transport in realistic fracture geometries remain quantitatively undefined. This study systematically investigates the transport of strontium (Sr) in fractured granite with and without BC, employing both column experiments and numerical simulations. The effects of varying hydrogeochemical conditions, including flow velocity (1.8–7.2 mL/h), pH (6.5–8.5), and ionic strength (0.001–0.1 M), were quantitatively evaluated. The results revealed that in the absence of colloids, Sr migration was primarily governed by non-equilibrium sorption interactions with the rock matrix. Lower flow velocities enhanced the solute residence time and interaction with the rock surface, promoting retention, while acidic conditions increased Sr mobility by reducing surface complexation. Crucially, the study reveals a complex dual role of BC dictated by hydrogeochemical thresholds. Under high flow velocity and low ionic strength, BC acted as effective carriers, facilitating Sr migration. In contrast, a distinct transition to transport inhibition was observed under low flow velocities or high ionic strength. Under these conditions, the stability of BC was compromised, leading to aggregation and straining within the fracture. This induced a site-shielding effect, where deposited colloids physically blocked sorption sites on the rock matrix, effectively retarding Sr transport. These findings challenge the generalized assumption of unconditional colloid-facilitated transport, underscoring the importance of incorporating specific hydrogeochemical thresholds in the safety assessment of HLW geological disposal systems.

准确预测裂隙结晶岩中放射性核素输运对高放废物地质处置的长期安全至关重要。然而，确定膨润土胶体（BC）在实际裂缝几何形状中是促进还是抑制放射性核素输运的具体阈值条件仍未定量确定。本文采用柱状实验和数值模拟两种方法，系统地研究了锶（Sr）在含BC和不含BC的破碎花岗岩中的运移。定量评价了流速（1.8 ~ 7.2 mL/h）、pH（6.5 ~ 8.5）、离子强度（0.001 ~ 0.1 M）等水文地球化学条件的影响。结果表明，在没有胶体的情况下，锶的迁移主要受与岩石基质的非平衡吸附作用的控制。较低的流速增加了溶质停留时间和与岩石表面的相互作用，促进了保留，而酸性条件通过减少表面络合作用增加了锶的迁移率。至关重要的是，该研究揭示了由水文地球化学阈值决定的BC的复杂双重作用。在高流速和低离子强度条件下，BC作为有效的载体，有利于Sr的迁移。相比之下，在低流速或高离子强度下观察到明显的转运抑制转变。在这些条件下，BC的稳定性受到损害，导致骨折内聚集和应变。这导致了一种位点屏蔽效应，即沉积的胶体物理阻塞了岩石基质上的吸附位点，有效地延缓了锶的迁移。这些发现挑战了无条件胶体促进运输的一般假设，强调了在高浓缩铀地质处置系统的安全评估中纳入特定水文地球化学阈值的重要性。

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引用次数: 0

Effects of transient air-water interfacial area on PFOA transport in unsaturated soil 瞬态气-水界面面积对非饱和土壤中PFOA迁移的影响

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

Journal of contaminant hydrology

Pub Date : 2026-01-16 DOI: 10.1016/j.jconhyd.2026.104859

Craig Klevan , Uriel Garza-Rubalcava , Linda M. Abriola, Kurt D. Pennell

Per- and polyfluoroalkyl substances (PFAS) may be retained in the vadose zone for extended periods due to adsorption on soil and at the air-water interface (AWI). While adsorption to the AWI has been shown to slow PFAS leaching, the magnitude of interfacial area can fluctuate with precipitation events, leading to its reduction or collapse. The objective of this study was to investigate PFAS mass transfer from the AWI into mobile pore water in response to changes in water saturation, and to determine the corresponding effects on PFAS transport through the soil profile. To quantify these processes, a combination of batch experiments and water-saturated and unsaturated column studies were performed with perfluorooctanoic acid (PFOA) and Appling soil. At 56% water saturation, the effluent PFOA breakthrough curve exhibited greater spreading than expected under equilibrium conditions, indicating rate-limited adsorption-desorption at the AWI. Under transient conditions, where the average water saturation increased from approximately 60% to 82%, the corresponding decrease in the AWI area led to a spike in effluent PFOA concentrations. These observations were accurately reproduced by a mathematical model that incorporated (1) symmetric rate-limited adsorption/desorption to/from the AWI, (2) regions of immobile water, as determined from non-reactive tracer data, and (3) a dynamic AWI area, as estimated using the Leverett model with a scaling factor. This work demonstrates the potential for precipitation events to temporarily increase PFAS leaching due to a reduction or collapse of the AWI and shows that these fluctuations can be predicted using an existing multiphase reactive transport simulator.

全氟烷基和多氟烷基物质（PFAS）由于在土壤和空气-水界面（AWI）上的吸附作用，可能长时间滞留在渗透区。虽然对AWI的吸附已被证明可以减缓PFAS的浸出，但界面面积的大小会随着降水事件而波动，从而导致其减少或崩溃。本研究的目的是研究随着水饱和度的变化，PFAS从AWI到可移动孔隙水中的传质，并确定PFAS通过土壤剖面的相应影响。为了量化这些过程，对全氟辛酸（PFOA）和施用土壤进行了批量实验和水饱和和不饱和柱研究。在56%含水饱和度下，出水PFOA突破曲线比平衡条件下的预期扩展更大，表明AWI的吸附-解吸速率有限。在瞬态条件下，平均含水饱和度从约60%增加到82%，AWI区域的相应下降导致出水PFOA浓度激增。这些观察结果通过一个数学模型精确地再现，该数学模型结合了(1)对AWI的对称速率限制吸附/解吸，(2)由非反应性示踪剂数据确定的不动水区域，以及(3)使用带有比例因子的Leverett模型估计的动态AWI区域。这项工作表明，由于AWI的减少或崩溃，降水事件可能会暂时增加PFAS浸出，并表明这些波动可以使用现有的多相反应输运模拟器进行预测。

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引用次数: 0

Nitrate source apportionments in the South Han River basin and its main tributaries using multi-isotopes and Bayesian approaches 基于多同位素和贝叶斯方法的南汉江流域及其主要支流硝酸盐源解析

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

Journal of contaminant hydrology

Pub Date : 2026-01-14 DOI: 10.1016/j.jconhyd.2026.104856

Hyeongseok Song , Kwang-Sik Lee , Nohsung Jeong , Sunghyen Cho , Dongguen Lee , Cheolho Yoon , Woo-Jin Shin

The nitrate apportionment approach provides valuable insights into efficient water quality management. Water samples were collected from the South Han River (SHR), and the three tributaries of the SHR showed relatively high nutrient levels. Water samples were collected from the North Han River (NHR), another contaminated stream (Gyeongan Stream, GA), and wastewater treatment plants (WWTP). The objectives of this study were to identify the sources impacting water chemistry in the SHR and its tributaries, especially nitrate contaminants, and to estimate the apportionment of nitrate sources. Plots of SO₄/Cl and NO₃/Cl showed relatively low ratios for the tributary, GA, and WWTPs samples compared to those of the SHR and NHR. Interestingly, samples from the lowest reaches of a tributary showed considerably high SO₄/Cl and low NO₃/Cl, with distinct δ³⁴S values, indicating a specific contaminant source in its watershed and subsequently influencing SHR water chemistry. The contributions of each source to nitrate in SHR and tributaries were estimated to be 58.9% to 93.3% and 0.2% to 95.7% for soil N and 15.9% to 40.3% and 4.1% to 99.4% for manure/domestic sewage, respectively, using a Bayesian isotope mixing model. These source contributions were not clearly consistent with the land-use patterns. δ¹¹B related to δ¹⁵N-NO₃ values for SHR samples indicate that domestic wastewater exerts a greater influence on water chemistry than agricultural inputs. We suggest a comprehensive approach for identifying nitrate contaminants in water using multiple isotopes, including nitrate isotopes, with a Bayesian isotope mixing model.

硝酸盐分配方法为有效的水质管理提供了有价值的见解。南汉江3条支流的水体营养水平均较高。从北汉江（NHR）、庆安江（GA）、污水处理厂（WWTP）等地采集了水样。本研究的目的是确定影响SHR及其支流水化学的来源，特别是硝酸盐污染物，并估计硝酸盐来源的分配。与SHR和NHR相比，支流、GA和WWTPs样品的SO4/Cl和NO3/Cl比值相对较低。有趣的是，一条支流最底层的样品显示出相当高的SO4/Cl和低的NO3/Cl，具有明显的δ34S值，表明该流域存在特定的污染源，并随后影响了SHR水化学。利用贝叶斯同位素混合模型估算出各来源对SHR和支流中硝态氮的贡献分别为58.9% ~ 93.3%和0.2% ~ 95.7%，对粪肥/生活污水的贡献分别为15.9% ~ 40.3%和4.1% ~ 99.4%。这些来源的贡献与土地利用模式并不明显一致。SHR样品的δ11B与δ15N-NO3值的相关关系表明，生活污水对水化学的影响大于农业投入。我们提出了一种综合方法，利用多种同位素，包括硝酸盐同位素，利用贝叶斯同位素混合模型来识别水中的硝酸盐污染物。

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引用次数: 0

Toward closed-loop remediation: A dynamic optimization approach for hydraulic conductivity estimation and pump-and-treat design 迈向闭环修复：水力导电性评估和泵处理设计的动态优化方法

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

Journal of contaminant hydrology

Pub Date : 2026-01-14 DOI: 10.1016/j.jconhyd.2026.104852

JunZe Wei , Simin Jiang , Qi Liu , Xun Zhang , Na Zheng , Jingwen Xing

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.

在污染场地的修复中，水导率场（k场）的准确性是影响修复效率的关键因素。传统方法依赖于稀疏的历史数据、短期抽水试验和静态插值方法，由于监测数据有限，往往无法捕获k场的异质性。这种不准确性导致修复设计不理想，从而导致成本增加和效率降低。为了解决这些局限性，本研究提出了一个动态迭代优化框架，该框架将参数反演与修复方案设计集成到模拟-观测-更新-优化的闭环系统中。该框架使用先导点参数化和模拟优化技术迭代更新k场，同时根据实时监测数据动态调整修复策略。在一个虚拟污染场地上进行的数值实验表明，所提出的框架显著提高了k场表征的准确性，并在迭代过程中降低了对数均方根误差（LRMSE）和增加了空间相关系数（SCC）。重要的是，与传统的静态修复计划相比，动态修复计划设计一次，无需更新即可执行，动态修复框架在减少总泵送量的同时实现了更高的污染物去除率。这些结果突出了该框架在提高非均质含水层修复效果和降低运营成本方面的潜力，为复杂的污染场地管理提供了实用和适应性的解决方案。

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引用次数: 0

Key factors controlling transport of biochar colloids in porous media and the mutual effects with coexisting contaminants 控制生物炭胶体在多孔介质中运移的关键因素及其与共存污染物的相互影响。

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

Journal of contaminant hydrology

Pub Date : 2026-01-14 DOI: 10.1016/j.jconhyd.2026.104851

Wei Wei , Xinyu Huan , Ziyi Chen , Yuanyi Li

Large-scale application of biochar (BC) has been considered as an effective strategy for carbon sequestration, soil quality improvement, and water/soil remediation. Once introduced into soils, BC can disintegrate or fragment through physical, chemical and biological processes, resulting in the formation of BC colloids (BCCs) with particle size ranging from 1 to 1000 nm. Due to the small size, large surface area, and high surface activity, BCCs exhibit stronger colloidal stability in aquatic environments and higher mobility in porous media than the bulk BC particles. In particular, BCCs have much higher adsorption affinity for various contaminants, and thus may serve as vehicles for facilitating contaminants transport, posing potential risks to the environment and human health. In this review, we summarize the current state of knowledge on the transport of BCCs influenced by (1) the intrinsic physicochemical properties of BCCs (i.e. pyrolysis temperature, size, aging effect), (2) solution chemistry (i.e. pH, ionic strength, ionic composition), (3) inorganic/organic colloids (i.e., minerals, humic/fulvic acid), (4) flow conditions (i.e. flow velocity), and (5) properties of porous media (i.e. grain size, media type and surface properties, moisture and mineral content). In addition, differing from previous works, this review provides a systematic analysis of BCCs transport through an integrated lens of governing mechanisms and mathematical models, with a dedicated focus on the mutual effects between BCCs and contaminants—a critical yet underexplored area determining their combined environmental fate. Finally, this work concluded with remarks on the importance of BCCs transport in porous media and directions for future research.

生物炭（BC）的大规模应用被认为是固碳、改善土壤质量和修复水土的有效策略。BC一旦进入土壤，就会通过物理、化学和生物过程分解或破碎，形成粒径为1 ~ 1000nm的BC胶体（BCCs）。由于体积小，表面积大，表面活性高，bcc在水生环境中表现出更强的胶体稳定性，在多孔介质中表现出更高的流动性。特别是，bcc对各种污染物具有更高的吸附亲和力，因此可能成为促进污染物运输的载体，对环境和人类健康构成潜在风险。在这篇综述中，我们总结了目前关于bcc运输受以下因素影响的知识现状：(1)bcc的固有物理化学性质（即热解温度、尺寸、老化效应），(2)溶液化学（即pH、离子强度、离子组成），(3)无机/有机胶体（即矿物、腐植酸/黄腐酸），(4)流动条件（即流速），以及(5)多孔介质性质（即粒度、介质类型和表面性质、水分和矿物含量）。此外，与以往的工作不同，本文通过综合的控制机制和数学模型对bcc的运输进行了系统的分析，重点关注bcc和污染物之间的相互作用——这是一个决定它们共同环境命运的关键但尚未得到充分探索的领域。最后，对bcc在多孔介质中运移的重要性和未来的研究方向进行了总结。

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引用次数: 0

The influence of sediment content and salinity in estuarine areas on the settling velocity of microplastics 河口沉积物含量和盐度对微塑料沉降速度的影响。

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

Journal of contaminant hydrology

Pub Date : 2026-01-13 DOI: 10.1016/j.jconhyd.2026.104854

Yefeng Ji, Lu Cao, Yun Gao, Zhongyan Huo, Zhequan Leng, Qi Chen, Zhutao Ding, Ying Xiong

Since their emergence in the 20th century, plastics have been extensively utilized worldwide. Owing to their pronounced hydrophobicity, chemical inertness, and resistance to microbial degradation, plastics persist in the environment and are difficult to eliminate. Rivers serve as an important pathway for microplastics (MPs) to flow into the ocean. The mechanisms that affect the migration, transportation and fate of MPs in rivers are not yet clear. This poses obstacles to understanding the dynamics of MPs in the ocean, determining their main aggregation areas, and conducting sampling in the ocean. Through a comprehensive series of settling experiments, this study demonstrates that the settling dynamics of MPs are significantly modulated by suspended solid concentration (SSC) and salinity gradients—factors that are particularly characteristic of estuarine transition zones at the river–ocean interface. The results indicate that SSC significantly enhance the settling velocity of MPs, with a maximum increase of 15.6%. However, this promoting effect diminishes as sediment concentration increases, and an inhibitory effect emerges under high concentrations. Conversely, elevated salinity markedly suppresses settling velocity, with a maximum reduction of 33.96%, though the magnitude of this influence gradually decreases with further increases in salinity. Based on the experimental results, a modified settling velocity model that integrates the effects of SSC and salinity was developed. Validation indicates that the model reliably predicts MPs settling velocity under a wide range of environmental conditions. This study provides a theoretical framework for advancing the understanding of MPs transport processes in estuarine and coastal environments and offers valuable insights for marine environmental management and remediation.

自20世纪出现以来，塑料在世界范围内得到了广泛的应用。由于其明显的疏水性、化学惰性和抗微生物降解性，塑料在环境中持续存在并且难以消除。河流是微塑料（MPs）流入海洋的重要途径。影响河流中MPs迁移、运输和命运的机制尚不清楚。这对了解海洋中MPs的动态，确定其主要聚集区域以及在海洋中进行采样构成了障碍。通过一系列全面的沉降实验，本研究表明，悬浮固体浓度（SSC）和盐度梯度显著调节了MPs的沉降动力学，这是河海界面河口过渡带特有的因素。结果表明，SSC显著提高了MPs的沉降速度，最大提高了15.6%。然而，随着沉积物浓度的增加，这种促进作用减弱，高浓度下出现抑制作用。相反，盐度升高显著抑制沉降速度，最大降低幅度为33.96%，但这种影响的幅度随着盐度的进一步升高而逐渐减小。在实验结果的基础上，建立了一个综合了SSC和盐度影响的沉降速度修正模型。验证表明，该模型能够在较宽的环境条件下可靠地预测MPs沉降速度。本研究为进一步了解MPs在河口和沿海环境中的迁移过程提供了理论框架，并为海洋环境管理和修复提供了有价值的见解。

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引用次数: 0

Response of microplastic color to photoaging and its influence on the release characteristics of derived dissolved organic matters 微塑料颜色对光老化的响应及其对衍生溶解有机质释放特性的影响。

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

Journal of contaminant hydrology

Pub Date : 2026-01-09 DOI: 10.1016/j.jconhyd.2026.104849

Maocai Shen , Shiwei Liu , Haokai Li , Ruixin Jin

This study systematically investigated the regulatory mechanisms of color parameters on the photoaging behavior and ecological effects of polypropylene (PP) and polymethylmethacrylate (PMMA). We revealed the evolution of the physicochemical properties of various colored microplastics. These results indicate that red and yellow microplastics significantly accelerated surface oxidation and chain breakage due to their strong ultraviolet absorption properties (long wavelength of 380–420 nm). This led to an increase in specific surface area, exemplified by a 10.8% increase in the crystallinity of red PP, an enhancement in surface roughness characterized by dense cracks on the surface of red PMMA, and a greater release of dissolved organic matter (MPs-DOM). DOM components exhibited color dependence, with the red group displaying the highest peak fluorescence intensity. PMMA was primarily composed of humic acids (Ex/Im = 240–250/420–425 nm), while PP released polycyclic aromatic hydrocarbons (Ex/Im = 220–225/305–310 nm). Biological toxicity experiments demonstrated that PMMA-DOM aged for 30 days significantly inhibited the germination rate of Chinese cabbage seeds, averaging 92%. Red PP-DOM promoted a 22.7% increase in seed wet weight during the early stage (10 d). However, long-term exposure (90 days) inhibited the activities of superoxide dismutase (SOD) and catalase (CAT) due to the accumulation of free radicals. Further research has shown that green microplastics exhibit weaker light absorption capabilities and lower toxicity effects related to DOM. This study elucidates the mechanism by which color influences the environmental fate of microplastics through their photoresponsive properties, providing a theoretical foundation for microplastic control strategies based on pigment photosensitivity.

本研究系统地研究了颜色参数对聚丙烯（PP）和聚甲基丙烯酸甲酯（PMMA）光老化行为和生态效应的调控机制。揭示了各种有色微塑料理化性质的演变过程。结果表明，红色和黄色微塑料具有较强的紫外吸收特性（长波380 ~ 420 nm），可显著加速表面氧化和链断裂。这导致了比表面积的增加，例如，红色PP的结晶度增加了10.8%，表面粗糙度增强，其特征是红色PMMA表面有密集的裂缝，溶解有机物（MPs-DOM）的释放量增加。DOM组分具有颜色依赖性，红色组荧光强度峰值最高。PMMA主要由腐植酸组成（Ex/Im = 240 ~ 250/420 ~ 425 nm）， PP主要由多环芳烃组成（Ex/Im = 220 ~ 225/305 ~ 310 nm）。生物毒性试验表明，PMMA-DOM陈化30 d显著抑制大白菜种子发芽率，平均为92%。红PP-DOM在前期（10 d）促进种子湿重增加22.7%。然而，长期暴露（90天）由于自由基的积累，抑制了超氧化物歧化酶（SOD）和过氧化氢酶（CAT）的活性。进一步研究表明，绿色微塑料的光吸收能力较弱，对DOM的毒性作用较低。本研究阐明了颜色通过光敏性影响微塑料环境命运的机制，为基于色素光敏性的微塑料控制策略提供了理论基础。

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引用次数: 0