Environmental Technology & Innovation最新文献

{"title":"Root surface microbial biofilms in phytoremediation: Formation processes, regulatory mechanisms, influencing factors and roles","authors":"Yibo Liu ,&nbsp;Zhenxue Dai ,&nbsp;Dayong Wang ,&nbsp;Yue Ma ,&nbsp;Ping Guo","doi":"10.1016/j.eti.2025.104406","DOIUrl":"10.1016/j.eti.2025.104406","url":null,"abstract":"<div><div>Root surface microbial biofilm (RSMB), formed by microorganisms colonizing plant root surfaces, constitutes the critical interface between soil environment and root system during phytoremediation. However, the mechanisms underlying RSMB formation and its roles in phytoremediation have not been comprehensively reviewed. This review integrates knowledge from microbial ecology, environmental science, and plant physiology to critically analyze the formation processes, regulatory mechanisms, influencing factors, and roles of RSMB in phytoremediation. RSMB formation unfolds in cyclical stages, including cell adhesion, microcolony formation, biofilm maturation, disintegration, and regeneration. Regulatory mechanisms are orchestrated by root exudates, which act as both nutrient sources and signaling molecules to induce microbial chemotaxis and biofilm formation ability. Additionally, communication activities among microorganisms via chemical and non-chemical signals further modulate biofilm development. RSMB formation is influenced by a combination of factors, including plant species, environmental conditions, nutrient availability, enzymes, antimicrobial peptides, biosurfactants, etc., bringing complexity to biofilm dynamics. Functionally, RSMB contributes to phytoremediation through various mechanisms. It can activate pollutants or improve plant physiology and growth to promote pollutant migration into plant systems; immobilize pollutants, degrade pollutants, or mediate pollutant volatilization to reduce pollutant migration into plant systems. Looking ahead, this review advocates for a paradigm shift toward mechanistic dissection of RSMB. We emphasizie integrating high-resolution microscopy imaging systems, multi-omics analysis techniques, and artificial intelligence simulation techniques to unravel their ecological roles and advance sustainable bioremediation approaches.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104406"},"PeriodicalIF":7.1,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724076","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics and sustainable use of fine-grained sediment in the Three Gorges Reservoir, China","authors":"Xian Zhou ,&nbsp;Zhongwu Jin ,&nbsp;Xia Chen ,&nbsp;Yinjun Zhou ,&nbsp;Zeyu Fan ,&nbsp;Dongfang Liang ,&nbsp;Xian Wu ,&nbsp;Chao Guo","doi":"10.1016/j.eti.2025.104413","DOIUrl":"10.1016/j.eti.2025.104413","url":null,"abstract":"<div><div>Reservoir siltation poses a global threat to sustainable water resource management. The Three Gorges Reservoir (TGR), one of the largest hydropower projects globally, faces significant challenges from fine-grained sediment accumulation (&lt;0.031 mm). This study systematically examines the physicochemical properties, siltation dynamics, and resource recovery potential of TGR sediments through integrated analyses, including X-ray diffraction, particle size distribution, and chemical characterization. The mud fraction was identified as rich in quartz and layered silicate clay minerals with alkali-activation activity, whereas the sand fraction primarily comprised quartz and anorthite, functioning as an inert filler. Novel eco-brick formulations utilizing dredged sediment were developed, including mud-sand composites with unconfined compressive strength (UCS) up to 12.8 MPa and cement-stabilized variants exceeding 50 MPa. These formulations reduce CO₂ emissions by 74.2–85.1 % compared to conventional fired clay bricks, which is attributed to the elimination of energy-intensive calcination and partial cement replacement. Particle packing optimization via the Modified Andreasen &amp; Andersen model demonstrated that a 1:3 mud-to-sand ratio maximized packing density and mechanical performance. A sustainable utilization pathway was proposed, including the production of ecological aggregates and eco-bricks, which simultaneously provides a reservoir sedimentation adaptive strategy and delivers low-carbon construction materials compatible with circular economy principles.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104413"},"PeriodicalIF":7.1,"publicationDate":"2025-07-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144721809","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiological and biochemical characteristics of biocrust in closed opencast coal mining areas: A study in Inner Mongolia, China","authors":"Xueqiang Zhu ,&nbsp;Yuxi Liu ,&nbsp;Tong Shen ,&nbsp;Dongfu Qin ,&nbsp;Qingjun Meng ,&nbsp;Qiyan Feng","doi":"10.1016/j.eti.2025.104405","DOIUrl":"10.1016/j.eti.2025.104405","url":null,"abstract":"<div><div>The biocrust is crucial in controlling erosion in arid and semi-arid regions, particularly in closed opencast coal mining areas. However, there is a lack of research concerning biocrust's physiological and biochemical characteristics in these mining environments and their relationship with various environmental factors. This gap in knowledge hinders the practical application of biocrusts for soil erosion control. Consequently, this study employed fluorescent quantitative PCR and high-throughput sequencing to examine the bacterial abundance and community diversity of biocrusts in the closed opencast mine in Zhalainuoer, Inner Mongolia, China. The results indicated that biocrusts significantly enriched soil nutrients. The upper layer of the biocrust exhibited a marked increase in available nutrients and organic matter content compared to bare soil, while the lower layer showed elevated levels of available nutrients, total phosphorus, and organic matter content. The physiological properties of moss within the biocrust were critically influenced by coverage, with chlorophyll a and soluble protein content increasing alongside coverage, whereas malondialdehyde content decreased as coverage declined. Bacterial diversity, as measured by the Chao1 and Shannon indices, significantly increased in both layers of the biocrust compared to bare soil. The dominant bacterial groups in the biocrust layers primarily included <em>Proteobacteria</em>, <em>Actinobacteria</em>, and <em>Bacteroidetes</em> at the phylum level. At the genus level, the predominant groups comprised <em>Pseudarthrobacter</em>, <em>Sphingomonas</em>, and <em>Nocardioides</em>. Among environmental factors, available phosphorus exerted the strongest influence on bacterial community composition, while total nitrogen had the weakest effect. Biocrusts modify bacterial communities to effectively manage nutrient cycling, enhancing the presence of key functional groups such as <em>Actinobacteriota</em> for carbon fixation, <em>Nocardioides</em> for nitrogen mineralization, and <em>Acidobacteriota</em> for phosphorus solubilization. The findings of this study provide practical references for evaluating the physical and chemical properties and bacterial communities of biocrusts in mining areas, thereby offering a mechanistic framework for employing biocrusts in sustainable mine rehabilitation.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104405"},"PeriodicalIF":7.1,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144749540","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Near-infrared spectroscopy and machine learning to estimate the physical and chemical properties of soils cultivated with Ilex paraguariensis","authors":"Gabriela Naibo ,&nbsp;Jackson Freitas Brilhante De São José ,&nbsp;Caroline Cecchele Zanotelli ,&nbsp;Gustavo Pesini ,&nbsp;Bruno Brito Lisboa ,&nbsp;Luciano Kayser Vargas ,&nbsp;Jean Michel Moura-Bueno ,&nbsp;Claudimar Sidnei Fior ,&nbsp;Tales Tiecher","doi":"10.1016/j.eti.2025.104409","DOIUrl":"10.1016/j.eti.2025.104409","url":null,"abstract":"<div><div>Accurately estimating the chemical and physical properties of soil is crucial for monitoring nutrient dynamics in <em>Ilex paraguariensis</em>, aiming to enhance the efficiency and precision of fertilizer application. Nevertheless, the high costs associated with traditional analytical methods pose a significant barrier to their widespread use across numerous samples, underscoring the importance of developing more accessible techniques. Consequently, this study aimed to assess the efficacy of various combinations of multivariate methods and preprocessing techniques based on near-infrared spectroscopy in estimating the chemical and physical properties of soils cultivated with <em>I. paraguariensis</em> across five regions of Rio Grande do Sul (southern Brazil). These samples originated from the state’s five main yerba mate-growing regions: Região dos Vales (n = 6), Palmeira das Missões (n = 14), Alto Uruguai (n = 19), Nordeste Gaúcho (n = 19), and Alto Taquari (n = 49), totaling 107 samples. The analyzed chemical properties included pH in water, soil organic matter, available concentration of seven nutrients (phosphorus, potassium, sulfur, copper, zinc, boron, and manganese), and exchangeable concentration of aluminum, calcium, and magnesium). Clay content was evaluated as physical property. NIR spectra (780–2500 nm) were acquired for all soil samples. The multivariate learning models tested included partial least squares regression (PLSR) and support vector machines (SVM), combined with three spectral preprocessing techniques: detrending (DET), Savitzky-Golay derivative (SGD), and standard normal variate (SNV), with raw spectra (RAW) as the control. Model performance and preprocessing technique effectiveness were assessed using the coefficient of determination, root mean square error, and the ratio of performance to interquartile distance. The SVM showed superior predictive performance compared to PLSR, with preprocessing techniques improving estimation accuracy in the following order: RAW&lt;SNV&lt;DET&lt;SGD. The most effective results were achieved by combining SVM models with SGD preprocessing. These findings indicate that selecting the appropriate mathematical models significantly enhances prediction of physical and chemical soil properties in samples cultivated with <em>I. paraguariensis</em>.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104409"},"PeriodicalIF":7.1,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144749607","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Rainwater records of atmospheric nitrogen-bearing pollutants in a plateau city, China: Compositions, evolution, and sources","authors":"Zixuan Liu ,&nbsp;Shijun Mao ,&nbsp;Jie Zeng ,&nbsp;Qixin Wu ,&nbsp;Qing Ma ,&nbsp;Yangdanshu Liu ,&nbsp;Kunxiang Wang ,&nbsp;Xin Ge","doi":"10.1016/j.eti.2025.104411","DOIUrl":"10.1016/j.eti.2025.104411","url":null,"abstract":"<div><div>Rainfall-related nitrogen (N) deposition has important influences on the earth surface due to its various eco-environmental effects (e.g., water eutrophication, biodiversity decreases). However, the evaluation of wet N deposition in plateau urban areas has received little attention to date, particularly regarding the composition, historical variations, and sources. Here, rainwater in the typical plateau city (Kunming) was sampled daily from June 2022 to May 2023 for N chemical measurement, and the historical data was applied for comparison. The concentrations of measured rainwater N species components, including NH₄⁺ -N, NO₃^--N, and dissolved organic nitrogen (DON), were 0.46, 0.45, and 0.88 mg N L⁻¹, respectively. Accordingly, the wet deposition fluxes in dissolved total nitrogen (DTN) were 14.20 kg N ha⁻¹ yr⁻¹, close to the average level in southwest China, the NH₄⁺-N, NO₃^--N, and DON were 26.0 %, 24.8 %, and 49.2 % of DTN, respectively. The significant variation in N concentration (highest in November with the lowest rainfall amount) and wet N deposition fluxes (highest in August with the highest rainfall amount) were observed in this study, which highlighted the leading role of rainfall amount and air pollutant content on rainwater N relative to other environmental factors. Moreover, the stoichiometric method shows that agricultural and non-agricultural factors controlled the rainwater N. The correlation between historical atmospheric nitrogen-bearing pollutant emissions and wet N deposition fluxes reveals that local human activities and transboundary pollutants are the primary factors influencing the wet N deposition in such a plateau city (Kunming). This study provides beneficial observed data on wet N deposition in plateau urban regions, which is also helpful in assessing urban nitrogen-bearing pollution and managing anthropogenic N emissions in plateau cities.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104411"},"PeriodicalIF":7.1,"publicationDate":"2025-07-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144749345","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct spatiotemporal patterns and meteorological impacts of Gobi Desert and Taklimakan Desert dust storms over China","authors":"Nana Luo ,&nbsp;Junxiao Zou ,&nbsp;Xingguang Piao ,&nbsp;Hooi Ling Khoo ,&nbsp;Kun Jia ,&nbsp;Jinlong Fan ,&nbsp;Haishuo Wei ,&nbsp;Qiao Wang ,&nbsp;Xing Yan","doi":"10.1016/j.eti.2025.104393","DOIUrl":"10.1016/j.eti.2025.104393","url":null,"abstract":"<div><div>Dust storms frequently impact China, driven largely by dust emissions from the Gobi and Taklimakan Deserts-two of East Asia's most significant dust sources. However, fundamental differences in their patterns and associated feedback mechanisms-particularly involving thermal and atmospheric processes-remain to be quantified. Here, we propose a novel framework integrating a rigorous hierarchical analysis with dynamic thresholding to enhance the precision and robustness of the dust storm-associated coarse-mode aerosol optical depth (DUST-cAOD) retrievals. By improving the Brightness Temperature Difference (BTD) algorithm, our method achieves 10-minute-resolution DUST-cAOD observations from 2016 to 2023. We build 32,767 hierarchical regression models to isolate and compare meteorological impacts of dust storms originating from the two Deserts. Our analysis reveals an intensification in frequency and impact of Gobi Desert-sourced dust storms. Annual occurrences increased from 6.25 events (2016–2019) to 14 events (2020–2023). Spatially, these storms affect 28.35 % of China’s land area-exceeding Taklimakan-sourced Desert storms by 37 %-and impact threefold more people. Mechanistically, Gobi Desert dust storms amplify through a positive feedback loop: thermal forcing strengthens the subtropical ridge (STR), reduces dewpoint temperatures, and elevates cloud liquid water content. In contrast, Taklimakan Desert dust storms intensify primarily through coupled precipitation-evaporation feedbacks. This study establishes the first systematic comparison of distinct mechanisms governing dust storms originating from the Gobi and Taklimakan Deserts. Our findings provide critical scientific support for improved early warning systems, region-specific mitigation strategies, and comprehensive assessments of dust-climate interactions across East Asia.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104393"},"PeriodicalIF":6.7,"publicationDate":"2025-07-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716151","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adsorption of perchlorate in water by FeCl3/dodecyldimethylammonium-chloride-modified activated carbon: Synergistic effect and mechanistic study","authors":"Yuanxiang Shan ,&nbsp;Yannan Jia ,&nbsp;Xiaomei Wu ,&nbsp;Nannan Xu ,&nbsp;Zhendong Liu ,&nbsp;Lu Li ,&nbsp;Zhiwei Wang ,&nbsp;Wanting Feng ,&nbsp;Weixiao Gong ,&nbsp;Haichen Cui ,&nbsp;Zheng Wang","doi":"10.1016/j.eti.2025.104400","DOIUrl":"10.1016/j.eti.2025.104400","url":null,"abstract":"<div><div>Perchlorate (ClO₄^-) is a stable monovalent ion with a tetrahedral structure that is difficult to remove from the environment. In this study, granular activated carbon (GAC) was modified with FeCl₃ and the quaternary ammonium salt dodecyldimethylammonium chloride (DDAC) for the removal of perchlorate from water. The optimal reagent loading was found to be 2.5 g of GAC modified with 5 g of FeCl₃ and 2.5 mmol/L of DDAC, generating Fe(5)-DDAC-GAC with a perchlorate adsorption of 31.59 mg/g and removal rate of 62.62 %. The adsorption of ClO₄^- by modified activated carbon is more in line with the quasi-primary kinetic model and the Langer-Muir isotherm model. Fe(5)-DDAC-GAC showed good adsorption of perchlorate under weak-acidic to neutral conditions, with optimal adsorption at pH 4 (33.93 mg/g and a removal rate of 67.25 %). The effect of interfering ions on the adsorption of ClO₄^- decreased in the order CO₃^2- &gt; SO₄^2- &gt; BrO₃^- &gt; PO₄^3-. The saturated Fe(5)-DDAC-GAC could be regenerated by NaCl or ultrasonication, with NaCl regeneration being more efficient (66.6 % (NaCl) vs. 55.5 % (ultrasonication) of the initial adsorption capacity).</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104400"},"PeriodicalIF":6.7,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716150","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"g-C3N4 integrated with MoS2/BiVO4 as a 2D/2D/1D heterojunction for enhanced photocatalytic activity under sunlight and DSSC performances","authors":"D. Karthigaimuthu ,&nbsp;Arjun Kumar Bojarajan ,&nbsp;Aya A.H. Mourad ,&nbsp;Gopal Ramalingam ,&nbsp;Mohammed T. Alotaibi ,&nbsp;Elangovan Thangavel ,&nbsp;Abdel Hamid I. Mourad","doi":"10.1016/j.eti.2025.104382","DOIUrl":"10.1016/j.eti.2025.104382","url":null,"abstract":"<div><div>In this work, MoS₂/BiVO₄/g-C₃N₄ as a 2D/2D/1D ternary heterojunction was synthesized by a sonication assisted hydrothermal method for photodegradation of organic dye pollutants under direct sunlight and serves as counter electrodes for dye-sensitized solar cells (DSSC). The MoS₂/BiVO₄/g-C₃N₄ nanohybrid was confirmed to have a crystal structure using X-ray diffraction angles presented at 14.45°, 26.83° and 28.44°, its functional groups were shown by FT-IR spectroscopy at 598, 474 and 804 cm⁻¹ , its chemical composition was shown by XPS spectroscopy, including Mo 3d, S 2p, O 1 s, C 1 s, Bi 4 f, V 2p and N 1 s, optical studies were observed by UV-DRS spectroscopy at 652, 579 and 460 nm, and it had a narrowing band gap at 1.83 eV, respectively. Further SEM and HR-TEM studies display that self-assembled g-C₃N₄ nanorods and BiVO₄ nanoflakes were decorated on the MoS₂ nanosheet surface, formed as 2D/2D/1D nanostructures. In photocatalytic activity of crystal violet (CV) and rhodamine B (RhB) dyes for all samples, the MoS₂/BiVO₄/g-C₃N₄ hybrid exhibited the highest degradation efficiencies of 98 % and 96 %, respectively. The investigations of ESR, radical trapping, Mott-Schottky test and photoluminescence (PL) spectra strongly provide evidence for the Z-scheme catalytic mechanism of the MoS₂/BiVO₄/g-C₃N₄ hybrid. The MoS₂/BiVO₄/g-C₃N₄ counter electrode based fabricated DSSC exhibits J_sc, V_oc, FF % and power conversion efficiency (PCE %) of 5.54 mA cm⁻², 0.713 V, 0.63 % and 2.48 %, respectively, which is 2.6 times higher than the as-prepared DSSC from pristine MoS₂. The enhanced photocatalytic and photovoltaic activities were attributed to improved charge separation, shorter charge transfer distance, and stronger interfacial interaction by forming a Z-scheme (N-P-N) heterojunction between MoS₂, BiVO₄, and g-C₃N₄. This research is expected to provide new insights into the rational design and fabrication of highly effective Z-scheme MoS₂/BiVO₄/g-C₃N₄ as 2D/2D/1D nanohybrid for photocatalytic processes for wastewater treatment and DSSC energy conversion harvesting.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104382"},"PeriodicalIF":7.1,"publicationDate":"2025-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144724075","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantifying contributions from unmonitored point-source discharges in an urban river using optical and nitrate isotopic tracers under dry-weather conditions","authors":"Pilyong Jeon ,&nbsp;Haeseong Oh ,&nbsp;Seokwon Lee ,&nbsp;Min-Seob Kim ,&nbsp;Seonhwa Hong ,&nbsp;Kitae Baek ,&nbsp;Jin Hur","doi":"10.1016/j.eti.2025.104399","DOIUrl":"10.1016/j.eti.2025.104399","url":null,"abstract":"<div><div>Small-scale wastewater treatment facilities in urban streams often operate under less stringent management, yet their contributions to organic pollution can significantly impact aquatic ecosystems. Continuous monitoring of these discharges remains challenging, necessitating prompt assessment methods. This study applies an end-member mixing analysis (EMMA) approach using stable isotope ratios and optical indices to estimate the contribution of organic matter from small, unidentified point sources. To simplify source attribution and improve methodological efficiency, background DOM—primarily from baseflow and natural organic inputs—was treated as a single end-member. This approach reduces the complexity of end-member sampling while maintaining robust estimates of unknown point-source contributions.</div><div>Wastewater discharges from a swine wastewater treatment plant and two food-processing facilities were evaluated for their downstream impact. The EMMA model demonstrated that fluorescence index (FI) and biological index (BIX) provided the most reliable estimates of point-source contributions at downstream sites, yielding consistent results with both measured loading data and model outputs based on the dual nitrate isotope pair (δ¹⁵N-NO₃ - δ¹⁸O-NO₃). However, further downstream, the isotopic model yielded more robust assessments, likely due to its lower susceptibility to biogeochemical alternations during DOM transport compared to the spectroscopic indices. This study demonstrates the effectiveness of optical and isotopic tracers for point-source attribution in urban watersheds, particularly in irregularly monitored or unmonitored settings.</div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104399"},"PeriodicalIF":6.7,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144716152","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparisons on the lead-tolerance and physiological response of different Hydrangea paniculata cultivars to lead stress","authors":"Yiming Liu ,&nbsp;Shuangshuang Chen ,&nbsp;Wenjuan Chen ,&nbsp;Jing Feng ,&nbsp;Huijie Chen ,&nbsp;Yong Han ,&nbsp;Xiaohua Du ,&nbsp;Yanming Deng","doi":"10.1016/j.eti.2025.104376","DOIUrl":"10.1016/j.eti.2025.104376","url":null,"abstract":"<div><div>The rising lead (Pb) pollution highlights the need for remediation methods, with phytoremediation being an effective approach. <em>Hydrangea paniculata</em>, known for its specific capacity to absorb Pb, represents a promising option for phytoremediation Pb-contaminated soil. However, studies about Pb-tolerance among different cultivars and their physiological responses remain limited. Here, <em>H. paniculata</em> cultivar 'Polar Bear' was primarily treated with different concentrations of Pb(NO₃)₂ to identify the optimal treating level. Subsequently, 17 <em>H. paniculata</em> cultivars were exposed to the selected Pb(NO₃)₂ concentration to evaluate Pb-tolerance by measuring Pb content and translocation factors, following by principal component, correlation, variance, and cluster analyses. Thereafter, two representative cultivars with the strongest ('Little Lemon') and weakest ('Polar Bear') Pb-tolerance were selected to assess physiological responses to Pb stress. The results showed that 1.0 mmol·L⁻¹ Pb(NO₃)₂ is the optimal concentration. Furthermore, the 17 cultivars were classified into three categories: three cultivars exhibited strong tolerance, six showed moderate tolerance, and eight demonstrated weak tolerance. Additionally, the increased Pb content in leaves could serve as an indicator of Pb-tolerance. Compared to 'Polar Bear', 'Little Lemon' displayed significantly enhanced activities of antioxidant enzymes including SOD, POD, and CAT. These results indicated that Pb tolerance varies substantially across <em>H. paniculata</em> cultivars, and that antioxidant enzymes likely play a key role in this tolerance mechanism. This study not only suggests ideal cultivars for the phytoremediation of Pb-contaminated soil, but also lays a physiological foundation for further exploration of Pb-tolerant mechanism in <em>H. paniculata.</em></div></div>","PeriodicalId":11725,"journal":{"name":"Environmental Technology & Innovation","volume":"40 ","pages":"Article 104376"},"PeriodicalIF":6.7,"publicationDate":"2025-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144702175","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"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}