Journal of contaminant hydrology最新文献_第3页

Exploring the ecotoxicological impacts of microplastics on freshwater fish: A critical review

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2025.104514

Surajit Ghosh , Sukhendu Dey , Ahmadul Hoque Mandal , Auroshree Sadhu , Nimai Chandra Saha , Damià Barceló , Paolo Pastorino , Shubhajit Saha

Microplastics (MPs) have become ubiquitous in the environment, prompting significant concern among ecotoxicologists due to their potential toxic effects. These particles originate from various sources, including the fragmentation of larger plastic debris (secondary microplastics) and consumer products such as liquid soaps, exfoliants, and cleaning agents. The widespread use of plastics, coupled with inadequate waste management, poses a growing threat to ecosystem health worldwide. MPs are plastic particles composed of high-molecular-weight polymers that exhibit biochemical stability. Plastics break down into MPs and even smaller nanoplastics through various degradation mechanisms, such as exposure to UV radiation from sunlight and other environmental factors. Due to their resemblance to certain types of zooplankton and food particles, MPs are often ingested by fish, entering their digestive systems. Once inside, they do not remain solely in the gut; rather, they infiltrate the fish's circulatory and lymphatic systems, eventually distributing throughout various tissues and organs. Microplastics have been found in fish gills, muscles, liver, heart, swim bladders, ovaries, spinal cords, and even brains. The presence of MPs in these organs has been linked to significant adverse effects, including reproductive, neurological, hormonal, and immune system disruptions. This toxicity extends beyond fish, as bioaccumulation and biomagnification of MPs affect other organisms as well, marking MPs as a major anthropogenic stressor that impacts ecosystems at multiple levels. Research indicates that nearly all aquatic environments globally are at risk of MP contamination. Laboratory and field studies highlight fish as particularly susceptible to MP ingestion, though freshwater species have been less extensively studied than marine counterparts. After exposure, fish may suffer various health issues, either directly from MPs or from their interaction with other contaminants. The broader environmental implications of these laboratory findings and the specific role of MPs in increasing fish exposure to harmful chemicals remain topics of ongoing debate. This review aims to contribute to ecotoxicological insights on fish contamination by MPs and outline areas for future investigation.

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引用次数: 0

AQuA-P: A machine learning-based tool for water quality assessment AQuA-P：基于机器学习的水质评估工具。

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2025.104498

L. Díaz-González , R.A. Aguilar-Rodríguez , J.C. Pérez-Sansalvador , N. Lakouari

This study addresses the critical challenge of assessing the quality of groundwater and surface water, which are essential resources for various societal needs. The main contribution of this study is the application of machine learning models for evaluating water quality, using a national database from Mexico that includes groundwater, lotic (flowing), lentic (stagnant), and coastal water quality parameters.

Notably, no comparable water quality classification system currently exists. Five advanced machine learning techniques were employed: extreme gradient boosting (XGB), support vector machines, K-nearest neighbors, decision trees, and multinomial logistic regression. The performance of the models was evaluated using the accuracy, precision, and F1 score metrics. The decision tree models emerged as the most effective across all water body types, closely followed by XGB. Therefore, the decision tree models were integrated into the AQuA-P software, which is currently the only software of its kind. It is recommended that these innovative water classification models be used through the AQuA-P software to facilitate informed decision-making in water quality management. This software provides a probability-based classification system that contributes to a deeper understanding of water quality dynamics. Lastly, an open-access repository containing all the datasets and Python notebooks used in our analysis is provided, allowing for easy adaptation and implementation of our methodology for other datasets worldwide.

本研究解决了评估地下水和地表水质量的关键挑战，这是满足各种社会需求的基本资源。本研究的主要贡献是应用机器学习模型来评估水质，使用墨西哥的国家数据库，其中包括地下水，流动（流动），死水（停滞）和沿海水质参数。值得注意的是，目前没有类似的水质分类系统。采用了五种先进的机器学习技术：极端梯度增强（XGB）、支持向量机、k近邻、决策树和多项逻辑回归。使用准确性、精密度和F1评分指标来评估模型的性能。决策树模型在所有水体类型中最有效，XGB紧随其后。因此，将决策树模型集成到目前同类软件中唯一的AQuA-P软件中。建议通过AQuA-P软件使用这些创新的水分类模型，以促进水质管理中的知情决策。该软件提供了一个基于概率的分类系统，有助于更深入地了解水质动态。最后，提供了一个开放访问的存储库，其中包含我们分析中使用的所有数据集和Python笔记本，从而可以轻松地针对全球其他数据集调整和实施我们的方法。

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引用次数: 0

Effects of soil bulk density and corresponding soil infiltration rate on the migration and transformation of gibberellic acid 土壤容重及相应土壤入渗速率对赤霉素酸迁移转化的影响。

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2024.104488

Xiaolei Hu , Linxian Huang , Huihua Chen , Liang Chen , Paul H. Fallgren

High intensity agricultural activities can lead to a decrease in soil fertility and an increase in soil bulk density, which may significantly impact the migration and transformation of pesticides in soil. As a new widely-used micro-toxic pesticide, gibberellic acid (GA₃) is more soluble and hydrophilic than most pesticides, which could readily migrate throughout the soil during water infiltration and impact groundwater quality. In this study, the leaching of GA₃ in saturated soils with different bulk densities (1.15–1.75 g/cm³) and infiltration rates (0.2215–0.0017 mm/s) were analyzed using column experiments. The migration and distribution of GA₃ in the soil with a depth of 50 cm were also investigated. The results indicated that GA₃ could completely penetrate the soil with bulk densities less than 1.45 g/cm³, and GA₃ mass variation in the effluent was normally distributed. The maximum mass of GA₃ in the effluent was calculated using the equation M_outlet(max) = 79.01 t^-0.97 (R² = 0.9811), and 83.69–93.16 % mass of the added GA₃ migrated downward in the soil. The analysis of the distribution of GA₃ in the soil showed that GA₃ accumulated in the upper soil layers with depths of 0–25 cm (the total depth of soil was 50 cm). In addition, the residual and hydrolyzed GA₃ amounts in the soil were 75.07–96.47 % and 5–30 % of the added GA₃, respectively. Overall, the soil bulk density and irrigation volume determine what type of impact that GA₃ may potentially have on the environment.

高强度的农业活动会导致土壤肥力下降，土壤容重增加，这可能会严重影响农药在土壤中的迁移和转化。赤霉素（GA3）是一种广泛使用的新型微毒农药，与大多数农药相比，它的溶解性和亲水性更强，在水的渗透过程中很容易迁移到整个土壤中，影响地下水水质。本研究利用柱状实验分析了 GA3 在不同容重（1.15-1.75 g/cm3）和不同渗透速率（0.2215-0.0017 mm/s）的饱和土壤中的浸出情况。此外，还研究了 GA3 在 50 厘米深的土壤中的迁移和分布情况。结果表明，GA3 可以完全渗透到体积密度小于 1.45 g/cm3 的土壤中，且 GA3 在污水中的质量变化呈正态分布。根据公式 Moutlet(max) = 79.01 t-0.97 (R2 = 0.9811)计算出出水中 GA3 的最大质量，添加的 GA3 有 83.69-93.16% 的质量在土壤中向下迁移。GA3 在土壤中的分布分析表明，GA3 在 0-25 厘米深的上层土壤中积累（土壤总深度为 50 厘米）。此外，土壤中 GA3 的残留量和水解量分别为添加量的 75.07%-96.47% 和 5%-30%。总之，土壤容重和灌溉量决定了 GA3 可能对环境产生的潜在影响类型。

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引用次数: 0

Unravelling land-based discharge of microplastics in River Basantar of Jammu & Kashmir, India: Understanding sinking behaviors and risk assessments 解开印度查谟和克什米尔巴桑塔尔河微塑料的陆基排放：理解下沉行为和风险评估。

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2024.104490

Shaveta Padha , Rakesh Kumar , Yogesh Sharma , Anjali Dhar

Microplastics (MPs) are ubiquitous and are increasing globally, but there is limited information available on their presence in freshwater ecosystems. This research work aims to investigate the abundance, sinking behavior, and risk assessment of MPs in the freshwater River Basantar, Jammu & Kashmir, India. Microplastic abundance in sediments was recorded in the range of 1–6 items g⁻¹, with a mean abundance of 3 ± 1.594 item g⁻¹, whereas MPs in surface water ranged from 200 to 850 items L⁻¹ with a mean abundance of 530 ± 218.4 items L⁻¹ among 12 sites for sediments and 10 sites for surface water. Besides, the sinking behavior of MPs was analyzed through portioning coefficients (K_d) at sediments-surface water interface, which ranges from 0.71 to 2.50 L Kg⁻¹ for River Basantar. The most common shapes identified were fragments, fibres, and films, followed by pellets, foams, and lines. ATR-FTIR polymeric characterization reported polyethylene, polypropylene, polystyrene, polyethylene terephthalate, and polyvinyl chloride, and thus, polymeric risk assessment analysis was also evaluated and normally distributed in the River Basantar. Polymer Hazard Index was calculated across all the sites which observed to be polluted under risk categories “III” and “IV” for both the sediments and surface water samples. Pollution Load Index (PLI) calculated across all the sites was >1 depicting all the sites for both sediments and surface water sampling to be polluted. Pollution Risk Index was assessed and majority of surface water and sediment samples were observed to be under “Very high” risk category. The study, using principal component analysis and heatmap analysis, found that MPs are primarily a result of urbanization and anthropogenic actions, like industrial discharges, household wastes, and agricultural runoffs. This study highlights the significance of more investigation and coordinated efforts to solve the worldwide problem of plastic pollution in freshwater environments. Results data provide insight into the current state of MP contamination and will help government authorities implement strict rules and perform management interventions to reduce and monitor pollution levels in River Basantar. Future studies on the partitioning of MPs in sediments and surface water must be focused on aggregation, biofouling, plastic density & size, salinity, and flow behaviors to understand transport and deposition in rivers.

微塑料（MPs）无处不在，并且在全球范围内不断增加，但关于它们在淡水生态系统中的存在的信息有限。本研究工作旨在调查印度查谟和克什米尔淡水巴桑塔尔河中MPs的丰度，下沉行为和风险评估。沉积物中微塑料丰度在1 ~ 6项g-1之间，平均丰度为3±1.594项g-1，而地表水中微塑料丰度在200 ~ 850项L-1之间，12个沉积物点和10个地表水点的平均丰度为530±218.4项L-1。此外，通过沉积物-地表水界面的分配系数（Kd）分析了MPs的沉降行为，在Basantar河，分配系数范围为0.71 ~ 2.50 L Kg-1。最常见的形状是碎片、纤维和薄膜，其次是颗粒、泡沫和线条。ATR-FTIR聚合物表征报告了聚乙烯、聚丙烯、聚苯乙烯、聚对苯二甲酸乙二醇酯和聚氯乙烯，因此，聚合物风险评估分析也进行了评估，并在Basantar河中呈正态分布。计算了沉积物和地表水样品在“III”和“IV”风险类别下被污染的所有地点的聚合物危害指数。所有站点计算的污染负荷指数（PLI）为bbb1，描述了所有沉积物和地表水采样受到污染的站点。污染风险指数评估显示，大部分地表水和沉积物样本处于“非常高”的风险类别。该研究利用主成分分析和热图分析发现，MPs主要是城市化和人为活动的结果，如工业排放、家庭废物和农业径流。这项研究强调了更多调查和协调努力的重要性，以解决淡水环境中的塑料污染问题。结果数据提供了对MP污染现状的深入了解，并将帮助政府当局实施严格的规则和实施管理干预措施，以减少和监测Basantar河的污染水平。未来关于MPs在沉积物和地表水中分配的研究必须集中在聚集、生物污垢、塑性密度和尺寸、盐度和流动行为上，以了解河流中的迁移和沉积。

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引用次数: 0

Rural village as a source of microplastic pollution in a riverine and marine ecosystem of the southern Venezuelan Caribbean

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2025.104511

Jose F. Grillo , Adriana López-Ordaz , Andrés J. Hernández , Francis B. Gómez , Marcos A. Sabino , Ruth Ramos

Microplastics (MP) are widely distributed environmental pollutants with the potential to impact terrestrial and aquatic ecosystems. MP produced in urban areas are transported through rivers to marine environments, interacting with water, sediments and organisms along the way. To date, most studies have characterized MP pollution associated with urban centers. This study quantified the MP abundance associated with a representative rural community of the Southern Caribbean Coast of Venezuela, Chichiriviche de la Costa (Chichi), and its influence on a neighboring riverine and marine ecosystem. MP pollution was assessed in the dry and rainy season by sampling riverine water and sediments upstream and downstream of the village. Additionally, marine water, sediments and organisms (fish and sponges) were sampled in the bay. Samples were processed according to standardized protocols with strict quality control procedures. MP were characterized through ATR-FT-IR. The riverine water and sediments downstream of the village had a MP abundance that was 2.3 and 3.8 times higher than the upstream sampling site, respectively. A higher MP abundance was found in the sediments of the river mouth and the waters of the inner bay of Chichi, suggesting that the river was the main source of MP to the bay. MP were found in all marine organisms. The MP abundance in the waters of the inner bay of Chichi was 1.7 to 1197.3 times higher than previous studies conducted in urban centers of Latin America. Our study highlights the role of rural centers as sources of MP pollution.

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引用次数: 0

Sorption behavior of oxytetracycline on microplastics and the influence of environmental factors in groundwater: Experimental investigation and molecular dynamics simulation 地下水中土霉素对微塑料的吸附行为及环境因素的影响：实验研究和分子动力学模拟。

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2024.104489

Fengjia Liu , Dan Zhang , Yufei Ma , Mengyao Jing , Guijuan Li , Shengke Yang

Microplastics (MPs) and antibiotics can enter groundwater through the interaction of soil and surface water, and MPs as carriers of antibiotics can promote the migration of antibiotics and thus generate more serious ecological risks. Therefore, this paper used experimental and molecular dynamics (MD) simulation methods to investigate the sorption between four common types of MPs in groundwater, namely polyamide (PA), polystyrene (PS), polyvinyl chloride (PVC), and polyethylene (PE), and oxytetracycline (OTC) with high detection rate in groundwater. Additionally, the impact of environmental factors on sorption was examined. The sorption kinetics of the four types of MPs followed the pseudo-second-order kinetics model, and the sorption isotherms of OTC on PA, PE, and PVC were highly linear, suggesting that the electrostatic interaction was the main sorption mechanism. Both experimental and simulation results indicated that PA had the highest affinity for OTC, due to the effect of the formation of hydrogen bonding between the amide groups of PA and OTC. The primary way pH affected sorption was by altering the form in which OTC exists. The effects of the representative substances of protein-like component (bovine serum albumin) and humus-like component (humic acid) in dissolved organic matter varied but were generally inhibitory. Ions could influence the sorption process by competitive sorption or forming complexes with the OTC.

微塑料与抗生素可通过土壤与地表水的相互作用进入地下水，微塑料作为抗生素的载体可促进抗生素的迁移，从而产生更严重的生态风险。因此，本文采用实验和分子动力学（MD）模拟的方法，研究了地下水中检出率较高的聚酰胺（PA）、聚苯乙烯（PS）、聚氯乙烯（PVC）、聚乙烯（PE）四种常见MPs与土霉素（OTC）之间的吸附关系。此外，还考察了环境因素对吸附的影响。四种MPs的吸附动力学符合拟二级动力学模型，OTC对PA、PE和PVC的吸附等温线呈高度线性，表明静电相互作用是主要的吸附机理。实验和模拟结果均表明，PA对OTC的亲和力最高，这是由于PA与OTC酰胺基之间形成氢键的影响。pH影响吸附的主要方式是通过改变OTC存在的形式。溶解有机物中蛋白质样成分（牛血清白蛋白）和腐殖质样成分（腐殖酸）的代表性物质的作用各不相同，但普遍具有抑制作用。离子可以通过竞争性吸附或与OTC形成配合物来影响吸附过程。

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引用次数: 0

Optimizing coastal groundwater quality predictions: A novel data mining framework with cross-validation, bootstrapping, and entropy analysis 优化沿海地下水质量预测：一种具有交叉验证、自举和熵分析的新型数据挖掘框架。

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2024.104480

Abu Reza Md Towfiqul Islam , Md. Abdullah-Al Mamun , Mehedi Hasan , Mst. Nazneen Aktar , Md Nashir Uddin , Md. Abu Bakar Siddique , Mohaiminul Haider Chowdhury , Md. Saiful Islam , A.B.M. Mainul Bari , Abubakr M. Idris , Venkatramanan Senapathi

Investigating the potential of novel data mining algorithms (DMAs) for modeling groundwater quality in coastal areas is an important requirement for groundwater resource management, especially in the coastal region of Bangladesh where groundwater is highly contaminated. In this work, the applicability of DMA, including Gaussian Process Regression (GPR), Bayesian Ridge Regression (BRR) and Artificial Neural Network (ANN), for predicting groundwater quality in coastal areas was investigated. The optuna-based optimized hyperparameter is proposed to improve the accuracy of the models, including optuna-GPR and optuna-BRR as benchmark models. Combined cross-validation (CV) and bootstrapping (B) methods were used to build six predictive models. The entropy-based coastal groundwater quality index (ECWQI) was converted into a normalized index (ECWQIn), which was divided into five classes from very poor to excellent. The self-organizing map (SOM), spatial autocorrelation and fuzzy logic model were used to identify spatial groundwater quality patterns based on 12 physicochemical variables collected from 67 groundwater wells. The SOM analysis identified four distinct spatial patterns, including EC-TDS-Cl⁻, MgpH, Ca²⁺K⁺NO₃⁻, and HCO₃⁻SO₄²⁻Na⁺F⁻. The results showed that both the ANN (CV) and ANN (B) models performed better than other optuna-based models during the test phase (RMSE = 0.041, MAE = 0.026, R2 = 0.971, RAE = 0.15 = 21 and CC = 0.986) and (RMSE = 0.041, MAE = 0.025, R2 = 0.969, RAE = 0.119 and CC = 0.975), respectively. SO₄²⁻, Cl⁻ and F⁻ played an important role in the prediction accuracy. F- and SO₄²⁻ showed higher spatial autocorrelation, which affected groundwater quality degradation. In addition, the ANN (CV) and ANN (B) models showed a Gaussian distribution of model errors (small standard error, <1 %), indicating the stability of the model. These results indicate the efficiency of the ANN model in predicting groundwater quality in coastal areas, which would help regional water managers in real-time monitoring and management of sustainable groundwater resources.

研究新型数据挖掘算法（DMAs）在沿海地区模拟地下水质量的潜力是地下水资源管理的重要要求，特别是在地下水严重污染的孟加拉国沿海地区。本文研究了高斯过程回归（GPR）、贝叶斯岭回归（BRR）和人工神经网络（ANN）三种方法在沿海地区地下水水质预测中的适用性。为了提高模型的精度，提出了基于optuna的优化超参数，包括optuna-GPR和optuna-BRR作为基准模型。采用交叉验证（CV）和bootstrapping (B)相结合的方法建立了6个预测模型。将基于熵的沿海地下水水质指数（ECWQI）转化为归一化指数（ECWQIn），将其分为极差到优5个等级。利用自组织图（SOM）、空间自相关和模糊逻辑模型，基于67口地下水水井采集的12个理化变量，对地下水水质空间格局进行了识别。SOM分析确定了四种不同的空间模式，包括EC-TDS-Cl-、MgpH、Ca2+K+NO₃-和HCO₃- so₄2-Na+F-。结果表明，ANN （CV）和ANN (B)模型在测试阶段的表现均优于其他基于optuna的模型（RMSE = 0.041, MAE = 0.026, R2 = 0.971, RAE = 0.15 = 21, CC = 0.986）和（RMSE = 0.041, MAE = 0.025, R2 = 0.969, RAE = 0.119, CC = 0.975）。SO42-、Cl-和F-对预测精度有重要影响。F-和SO42-表现出较高的空间自相关性，影响地下水水质退化。此外，ANN （CV）和ANN (B)模型的模型误差呈高斯分布(标准误差较小，

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引用次数: 0

Distribution of potentially toxic elements in sediments of the municipal river channel (Balu), Dhaka, Bangladesh: Ecological and health risks assessment

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2024.104492

Md Muzammel Hossain , Iffat Jahan , Abdullah Al Nahian , Karen H. Johannesson , Stephen J. Maxwell , Daochen Zhu

The concern of potential toxic elements (PTEs) contamination in the river ecosystem is growing due to anthropological activity. The contents of seven PTEs in sediments from the Balu River channel were analyzed using atomic absorption spectroscopy (AAS) and an environmental risk model. Several PTEs were found in the sediment at high levels, including zinc (Zn), copper (Cu), arsenic (As), lead (Pb), cadmium (Cd), nickel (Ni), and mercury (Hg), that might pose a risk to human and ecological health. The highest mean concentration of PTEs in sediment followed in decreasing order Zn (1365.21 mg/kg) > Cu (149.34 mg/kg) > Pb (46.34 mg/kg) > Ni (34.78 mg/kg) > As (6.31 mg/kg) > Cd (2.34 mg/kg) > Hg (1.03 mg/kg). In addition, most of these PTEs were significantly correlated (p < 0.05) among the sites and exceeded the safety guideline value. The geo-accumulation index (Igeo), contamination factor (CF), and pollution load index (PLI) showed high levels of PTEs contamination and moderately polluted to highly polluted levels of these elements. At the BL3, BL4, and BL6 sites within the study site, the ecological risk (PERI) score was extremely high, and the PERI values range found was from 75.39 to 355.72. Every PTE had a slightly greater concentration during the dry season than the wet season. Interestingly, PTE accumulation from sediment indicated non-carcinogenic risk (

{HQ}_{dermal}

) in human health, whereas most of the sites showed carcinogenic risk (

{CR}_{dermal}

) to human health (adult and child) due to Cd and Ni accumulation. Multivariate statistical analysis (MVSA) indicated the most likely anthropological sources were the untreated wastes discharged in the river sampling area. People who come into contact with polluted sediments are constantly exposed to Ni and Cd pollution, which increases the risk of cancer and non-cancerous diseases. So, continuous PTE monitoring is advised by this study to assess ecological and human health risks.

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引用次数: 0

Induced polarization monitoring of in-situ chemical oxidation for quantification of contaminant consumption 原位化学氧化诱导极化监测用于污染物消耗的量化。

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2024.104481

Teng Xia , Johan Alexander Huisman , Chen Chao , Jing Li , Deqiang Mao

Dynamic monitoring of in-situ chemical oxidation (ISCO) of LNAPLs in groundwater is the foundation for evaluating remediation effectiveness. In this study, spectral (SIP) and time-domain induced polarization (TDIP) measurements are conducted in laboratory columns and sandboxes to monitor the ISCO of LNAPL for characterizing oxidant transport and quantifying contaminant consumption under different injection strategies. To support the interpretation, this was combined with total petroleum hydrocarbon (TPH), hydrochemistry and computed tomography (CT) measurements. Experiments were performed using two media, and the monitoring results showed similar variations in key parameters. The electrical resistivity, chargeability and TPH decreased significantly during ISCO remediation, while the hydrochemical parameters showed an increasing trend. Specifically, IP variations before and after injection revealed that more oxidant remained in the source area using a multiple-injection strategy compared to a single-injection strategy. The effect of contaminant consumption under well-controlled conditions on electrical resistivity was <3 % and the effect on chargeability was <8 %. In conditions with oxidant migration, the effect of oxidant on the resistivity and chargeability was similar at ∼89 % in the source area, whereas the oxidant had a greater effect on the resistivity (>58 %) than the chargeability (<40 %) outside the source area. Based on the experimental results, a conceptual model for the IP response during ISCO remediation is proposed and we delineate the pore structural characteristics of porous media based on the conceptual model. Oxidant injection develops a high conductivity environment and causes a decrease in LNAPLs content and number of interfaces, leading to the suppression of the IP response. In conclusion, IP measurement in combination with supporting information clearly enables the characterization of the ISCO remediation of LNAPLs in groundwater and facilitates the pore structure characterization of porous media based on the IP conceptual model.

地下水中LNAPLs原位化学氧化（ISCO）的动态监测是评价修复效果的基础。在本研究中，通过光谱（SIP）和时域诱导极化（TDIP）测量在实验室色谱柱和沙盒中监测LNAPL的ISCO，以表征不同注入策略下的氧化剂运输和污染物消耗。为了支持解释，将其与总石油烃（TPH）、水化学和计算机断层扫描（CT）测量相结合。实验采用两种介质进行，监测结果显示关键参数变化相似。ISCO修复过程中，土壤的电阻率、充电率和TPH均显著降低，而水化学参数则呈上升趋势。具体来说，注入前后的IP变化表明，与单一注入策略相比，使用多次注入策略时，更多的氧化剂留在了源区域。在控制良好的条件下，污染物的消耗对电阻率的影响比可充电性(

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引用次数: 0

Effects of karst conduit structure on breakthrough curves: Experiments and modeling

IF 3.5 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Journal of contaminant hydrology

Pub Date : 2025-02-01 DOI: 10.1016/j.jconhyd.2025.104504

Tingqiao Yang, Guanping An, Xinhao Hu, Jinna Chen, Tao Huang

Due to the complexity of karst conduit systems, field tracer tests can produce a variety of breakthrough curves (BTCs) and present challenges in analyzing BTCs and determining solute transport pathways. In this study, tracer experiments were conducted in the laboratory using karst pipe structures such as asymmetric branch pipe and pool models to investigate the effect of karst conduit structure on BTC. Subsequently, experimental BTCs were simulated using the OM-MADE (One Dimensional Model of Multiple Adsorption, Diffusion, and Storage in Exchange Zones) model, and the results were compared with the experimental results. The results show that the main pipe in the branch pipe model significantly affects the number of BTC peaks, with increasing two-branch pipe spacing (D_L) leading to a decrease in peak concentration and delaying peak time. In the pool model, increasing the pool volume or number leads to lower peak concentrations and stronger tailing effects. In the continuous pool model, the outlet location has the most significant influence on the BTC morphology. The OM-MADE model accurately simulates the bimodal and trailing features of the BTCs (R² ≥ 0.9), demonstrating its reliability in predicting groundwater contamination. This study provides key insights that can help predict and manage groundwater contamination.

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