Jon C King, Austin Shamblin, Devin North, Calissa Carlisle, Kien A Vu, Kyle Bibby, Karen C Dannemiller
{"title":"Evaluation of targets for normalization of viral pathogen concentrations in building dust.","authors":"Jon C King, Austin Shamblin, Devin North, Calissa Carlisle, Kien A Vu, Kyle Bibby, Karen C Dannemiller","doi":"10.1039/d6em00345a","DOIUrl":"10.1039/d6em00345a","url":null,"abstract":"<p><p>Building dust is potentially an important public health tool for monitoring human pathogens because it contains genetic material from pathogens. However, building dust is heterogeneous and presents technical challenges for environmental pathogen surveillance. To effectively use pathogen measurements in building dust for environmental surveillance, normalization procedures that account for human contribution to dust may be necessary and could help account for variability in occupancy and temporal resolution. Our analysis investigates potential indicators of human emission that could be used to normalize data on concentration of pathogens in dust. Ninety-nine vacuum dust samples were collected from 33 buildings and concentrations were measured for three emission indicators (<i>i.e.</i>, human cytochrome B gene, <i>Carjivirus communis</i> (previously crAssphage), and pepper mild mottle virus) and two respiratory pathogens (<i>i.e.</i> SARS-CoV-2 and influenza A virus). All of these were detected in ≥91% of the samples, with the exception of influenza A virus (73%). Most pairings of indicators (nine of 10) showed a weak to moderate positive correlation with one another (Kendall's <i>τ</i> ≤ 0.28). Correlations between occupancy and emission indicators and respiratory pathogens were weak (Kendall's <i>τ</i> < |0.15|) and non-significant (<i>p</i> > 0.1). Among all potential markers, MT-CYB was most promising, with detection in 96% of the samples, higher concentration than others, and stronger correlation with other potential measures of occupancy.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-11-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13742303/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149356963","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Painted wallboard provides a rapid, high-capacity reservoir for indoor volatile organic compounds.","authors":"Jixuan Wang, Shuqi Wang, Yingjun Liu","doi":"10.1039/d6em00758a","DOIUrl":"https://doi.org/10.1039/d6em00758a","url":null,"abstract":"<p><p>Indoor surfaces buffer airborne concentrations of volatile organic compounds (VOCs) and thereby influence human exposure. Field studies have inferred a house-averaged reservoir equivalent to a micrometer-thick octanol film for weakly polar VOCs, with still greater capacity for polar compounds; yet the physical identity of this reservoir remains unresolved. We quantified uptake and release of 14 target VOCs by painted wallboard, which is responsible for a substantial fraction of exposed surfaces in indoor built environments. Sorption experiments were conducted both on complete wallboard assembly (comprising latex paint, skim coat, and gypsum board) and on its constituent layers, at room temperature and 50% relative humidity. For weakly polar compounds, fitting wallboard desorption kinetics yielded a median octanol-equivalent reservoir thickness of approximately 80 µm per unit wallboard area, sufficient to account for house-averaged field estimates when scaled by indoor prevalence of painted wallboard. The three water-soluble compounds tested exhibited several-fold greater sorption than less water-soluble compounds of comparable volatility. Comparative material experiments indicated that VOCs traversed the paint and skim coat and partitioned into the underlying gypsum board, which contributed >50% of total sorption for 8 of the 11 equilibrated compounds and 76-91% for the 3 water-soluble compounds. These results identify painted gypsum wallboard as a plausible major contributor to indoor VOC reservoirs and suggest that building materials can prolong indoor VOC persistence, with implications for ventilation and inhalation exposure.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149331738","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Eutrophication control regulates sedimentary records and sediment-water exchange of dissolved polycyclic aromatic hydrocarbons and polycyclic musks.","authors":"Qing-Nan Wang, Liang Wu, Jia-Xiong Wang, Xiang-Zhou Meng, Chen-Chou Wu, Lian-Jun Bao, Eddy Y Zeng","doi":"10.1039/d6em00668j","DOIUrl":"https://doi.org/10.1039/d6em00668j","url":null,"abstract":"<p><p>Understanding the fate of hydrophobic organic compounds under eutrophication management is critical for assessing aquatic ecological risks in inland lakes. In the present study, passive samplers were deployed in two eutrophic lakes (Lake Taihu and Lake Gehu, China) to investigate the occurrences and sediment-water exchange dynamics of dissolved polycyclic aromatic hydrocarbons (PAHs) and polycyclic musks. The dissolved concentrations of PAHs were 2.4-160 ng L<sup>-1</sup> in overlying water and 7.5-55 ng L<sup>-1</sup> in sediment porewater, whereas the levels of galaxolide (HHCB), only detected polycyclic musk, ranged from 0.08-47 and 0.93-29 ng L<sup>-1</sup>, respectively. Sediment records showed that the clear declines in accumulations of PAHs and HHCB may be associated with eutrophication-control and wastewater-management measures. Source analysis revealed that combustion emission and domestic wastewater were the major contributors to dissolved PAHs and HHCB. The sediment-water diffusion fluxes of PAHs and HHCB varied between -15 and 21 ng m<sup>-2</sup> d<sup>-1</sup>. Sediment acted as a source for 3- and 4-ring PAHs in the overlying water. The contents of organic matter in sediment induced by eutrophication and temperature may regulate the exchange of 5-ring PAHs (BbF, BaP, and PER) and HHCB, respectively. These findings underscore the need for continued control of industrial combustion and domestic wastewater inputs to reduce organic pollution in these eutrophic lakes.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-11-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149316130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Katharina J Neubert, Susanne Walch, Michael Schloter, Nicolas Brüggemann
{"title":"Microplastics affect belowground performance of winter wheat and microbial networks in the rhizosphere.","authors":"Katharina J Neubert, Susanne Walch, Michael Schloter, Nicolas Brüggemann","doi":"10.1039/d6em00205f","DOIUrl":"https://doi.org/10.1039/d6em00205f","url":null,"abstract":"<p><p>Microplastics (MPs) are increasingly recognized as environmental pollutants affecting soil ecosystems and plant development, but their specific impacts on plant-soil-microbiome interactions remain unclear. This study investigated the effects of different MP types, including particulate polypropylene (PP), low-density polyethylene (LDPE), polystyrene (PS), and fibrous polyester (PES), individually on early-stage winter wheat root growth, nutrient concentrations, soil conditions and the rhizosphere microbiome using rhizotrons. Our findings revealed that PP and PES MPs significantly reduced root length. We observed increased soil ammonium concentrations with the addition of all MPs, likely due to reduced nitrifying bacterial activity, while PS MP enhanced soil nitrate concentration, potentially reflecting impaired root absorption. Because polymer size and morphology covaried, the results are interpreted as MP-type-specific. No significant effects of MPs on plant potassium (K) and phosphorus (P) uptake were observed. Despite changes in soil nutrient levels, we found no significant alterations in leaf growth, nutrient uptake, or chlorophyll content, indicating that root systems, though affected by MPs, remained sufficiently functional to support shoot development. Microbial co-occurrence analysis revealed two distinct microbial clusters in the rhizosphere, confirming modular microbial structure. Among all treatments, LDPE exposure induced the most pronounced increase in network complexity, as reflected by higher edge density, clustering coefficient, and natural connectivity compared to the control. Many amplicon sequence variants (ASVs), <i>e.g.</i>, members of Vicinamibacteraceae, <i>Pseudolabrys</i> and <i>Nitrospira japonica</i>, showed an increased degree and eigenvector centrality in the LDPE treatment, suggesting enhanced co-occurrence and higher influence within the microbial community structure. In contrast, the PES and PP treatments resulted in lower average node degree and reduced clustering. The PS treatment only had a small effect on the microbial co-occurrence networks. Overall, our data indicate that MP-induced stress can alter microbial network topology, reduce community integration, and drive shifts in ecologically important taxa in the rhizosphere, which are linked to changes in the availability of nutrients for plants. Our findings highlight the complex and variable influence of MPs on soil-plant interactions.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149316131","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yanan Li, Eric Fries, Gillian Z Miller, Jeff Gearhart, Dayton McGrail, Christopher D Kassotis, Roxana Sühring
{"title":"Correction: Emerging investigator series: unpacking PET: comparative analysis of leachable and extractable contaminants from virgin and recycled polyethylene terephthalate bottles and textiles.","authors":"Yanan Li, Eric Fries, Gillian Z Miller, Jeff Gearhart, Dayton McGrail, Christopher D Kassotis, Roxana Sühring","doi":"10.1039/d6em90037b","DOIUrl":"https://doi.org/10.1039/d6em90037b","url":null,"abstract":"<p><p>Correction for 'Emerging investigator series: unpacking PET: comparative analysis of leachable and extractable contaminants from virgin and recycled polyethylene terephthalate bottles and textiles' by Yanan Li <i>et al.</i>, <i>Environ. Sci.: Processes Impacts</i>, 2025, <b>27</b>, 3431-3439, https://doi.org/10.1039/D5EM00615E.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149316129","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Miko Doeze Jager, Eros Reij, Daniel Probst, Gabriel Sigmund
{"title":"Scoping when bit length of molecular fingerprints determines the reliability of computational tools in environmental chemistry and toxicology.","authors":"Miko Doeze Jager, Eros Reij, Daniel Probst, Gabriel Sigmund","doi":"10.1039/d6em00634e","DOIUrl":"https://doi.org/10.1039/d6em00634e","url":null,"abstract":"<p><p>Many modern computational tools to describe or predict the behaviour of organic chemicals rely on molecular fingerprints. Fingerprints are used as descriptors for structure-activity relationship modelling and structure-based clustering of chemicals across the fields of environmental chemistry, technology and (eco)toxicology. Here, we highlight how Extended Connectivity Fingerprint (ECFP), RDKit fingerprint, Atom Pair fingerprint, and Torsion fingerprint, among others, are susceptible to \"bit collisions\", which result in the same fingerprint for different molecular structures in a given dataset. Bit collisions can be introduced during hashing, where two distinct fragments result in the same hash, or more commonly, where the folding operation assigns two different structures to the same bit index. These collisions can occur at the molecular level, where two distinct substructures in a molecule collide, or at the dataset level, where collisions occur due to molecular aggregation. Using two curated datasets (pesticide degradation and global chemical inventory data), we show that bit collision is inversely related to the bit size of fingerprints and is more pronounced in Atom Pair and RDKit fingerprints compared to ECFP and Torsion fingerprints. In addition, molecular size and atom count are positively related to bit collisions. At the widely used ECFP4 with a bit length of 1024, bit collisions occurred for approximately 50% of the molecules in both tested datasets. Finally, we showcase how bit collisions can be detrimental for predictive modelling of targets with high certainty, such as hydrophobicity, while their effect is less visible for more uncertain and \"noisy\" targets such as persistence. Overall, this study provides guidance on fingerprint and bit size selection for predictive modelling in environmental chemistry, ecotoxicology and environmental technology.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149316132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiangtian Wang, Yan Lin, Wei Hu, Nathaniel Rothman, Jason Y Y Wong, George S Downward, Roel Vermeulen, Qing Lan, Junfeng Jim Zhang
{"title":"Urinary PAH carboxylic acids as exposure biomarkers for methylated PAHs linked to urinary mutagenicity.","authors":"Xiangtian Wang, Yan Lin, Wei Hu, Nathaniel Rothman, Jason Y Y Wong, George S Downward, Roel Vermeulen, Qing Lan, Junfeng Jim Zhang","doi":"10.1039/d6em00417b","DOIUrl":"https://doi.org/10.1039/d6em00417b","url":null,"abstract":"<p><p>Emerging evidence suggests that methylated polycyclic aromatic hydrocarbons (methyl-PAHs) exhibit greater carcinogenic potential than their unsubstituted parent PAHs. Previous studies in Xuanwei, China, reported elevated lung cancer risk among non-smoking women exposed to smoky coal and high ambient levels of methyl-PAHs, including 5-methylchrysene (5-MC). We conducted biomonitoring to evaluate internal dose markers of methylated PAHs including five PAH carboxylic acids (PAH-CAs) and dose markers of unsubstituted PAHs including five hydroxylated PAHs (OH-PAHs) in 48 women using four household fuel types (smoky coal without chimney, smoky coal with chimney, smokeless coal, and electricity). Urinary OH-PAHs and PAH-CAs showed a decreasing gradient from smoky coal without chimney to electric cooking. When contrasting smoky coal with chimney and smokeless coal, only PAH-CAs, particularly phenanthrene-2-carboxylic acid (2-PHECA) and dibenzofuran-4-carboxylic acid (4-DFCA), mirrored differences in airborne 5-MC and benzo[<i>a</i>]pyrene (BaP). Airborne 5-MC explained 50% of the variance in urinary 2-PHECA (<i>R</i><sup>2</sup> = 0.50), compared with 30% explained by BaP (<i>R</i><sup>2</sup> = 0.30). In 18 samples analyzed for mutagenicity, urinary 2-PHECA was strongly correlated with mutagenic potency (Spearman <i>ρ</i> = 0.74, <i>p</i> < 0.001), whereas 1-hydroxypyrene showed a weaker association (<i>ρ</i> = 0.49, <i>p</i> = 0.04). These findings suggest that PAH-CAs, particularly 2-PHECA, may serve as internal dose markers reflecting biologically relevant exposure to methylated PAHs associated with mutagenic potency.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149293309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Quentin Bollaert, Charlotte Catrouillet, Mélanie Davranche, Jean-Pascal Rueff, James M Ablett, Sandra Benter, Imane Khatib, Aicha El Kharraf, Anne-Catherine Pierson-Wickmann, Julien Gigault, Delphine Vantelon
{"title":"Beyond total lead (Pb) content: speciation as a key control on plastic toxicity.","authors":"Quentin Bollaert, Charlotte Catrouillet, Mélanie Davranche, Jean-Pascal Rueff, James M Ablett, Sandra Benter, Imane Khatib, Aicha El Kharraf, Anne-Catherine Pierson-Wickmann, Julien Gigault, Delphine Vantelon","doi":"10.1039/d6em00629a","DOIUrl":"https://doi.org/10.1039/d6em00629a","url":null,"abstract":"<p><p>Despite recent regulatory efforts, large amounts of legacy plastics containing lead (Pb) additives continue to degrade in the environment. As plastics degrade to micro- and nanoscales, Pb can either be released into the environment or subsequently adsorb onto micro- and nanoplastics. This variability in Pb speciation, with each form displaying distinct leaching behaviour, complicates environmental risk assessment. Here, we compile a dataset of plastic debris collected from beaches worldwide, revealing an average Pb concentration of 110 mg kg<sup>-1</sup>, with nearly 15% items exceeding current regulatory limits. A Pb-Cr relationship is observed in nearly half of the samples, which cluster along a Pb/Cr ratio close to 4, suggesting the presence of historical PbCrO<sub>4</sub> pigment and associated with low Pb availability. However, Pb L<sub>3</sub>-edge HERFD-XANES spectra indicate significant variability in Pb speciation, pointing to the presence of multiple, previously underrecognized Pb-based additives including organo-Pb compounds. Although these plastics do not contain the highest total Pb concentrations, those containing organic Pb additives exhibit the greatest Pb availability, demonstrating that bulk Pb content alone is a poor predictor of environmental behaviour upon degradation. The high spectral resolution of HERFD-XANES further allows the discrimination of incorporated and adsorbed Pb species, providing direct insights into Pb binding environment, leachability, and potential toxicity. Our results demonstrate that human-health risk assessments should not rely solely on total Pb concentrations, but rather on Pb speciation, which ultimately governs leaching behaviour and bioavailability.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-10-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149293265","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Li Wu, Yajie Wan, Mengdi Zhang, Tongqian Zhao, Yanxin Xiao
{"title":"Effects of hydrological changes on the sources and optical properties of dissolved organic matter in wetlands of the middle reaches of the Yellow River.","authors":"Li Wu, Yajie Wan, Mengdi Zhang, Tongqian Zhao, Yanxin Xiao","doi":"10.1039/d6em00491a","DOIUrl":"https://doi.org/10.1039/d6em00491a","url":null,"abstract":"<p><p>Dissolved organic matter (DOM) in riverine wetlands is the core carrier of the carbon cycle. However, the dynamics of DOM in large riverine wetlands subject to anthropogenic hydrological regulation remain poorly understood, and the differences in DOM composition and sources among hydrological periods are still unclear. In this study, water samples were collected from the riparian wetland in the Wuzhi section of the middle reaches of the Yellow River during the dry season (DS), normal season (NS), water-sediment regulation scheme (WSRS), and wet season (WS). Ultraviolet-visible (UV-vis) absorption spectroscopy and excitation-emission matrix (EEM) spectroscopy, combined with parallel factor analysis (PARAFAC), were used to characterize the composition and sources of DOM across hydrological periods. Two-dimensional correlation spectroscopy (2D-COS) was applied to reveal the ordered pattern of DOM fluorescent components along the flow direction. The results showed that DOM content, composition, and sources differed among periods. DOC concentration was highest during the WSRS, followed by that during the WS, and was lower during the DS and NS. Three components were identified. Humic-like components C1 and C3 peaked in the WS, whereas the protein-like component C2 peaked in the DS. Within the same season, the water-sediment regulation event caused a significant change in the fluorescence intensity of C2. Spectral parameters indicated that DOM in the WS may have been influenced by terrestrial and autochthonous sources, while autochthonous contributions appeared to be stronger in the other periods. 2D-COS analysis revealed an ordered pattern of DOM fluorescent components along the flow direction, following the sequence protein-like → microbial humic-like → terrestrial humic-like components. This pattern may be influenced by multiple processes including tributary input, agricultural runoff, and sediment release. This study helps to address the limited understanding of DOM dynamics in wetlands under hydrological disturbance and provides baseline data for interpreting the compositional changes and along flow variation patterns of DOM in riparian wetlands across hydrological periods.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":""},"PeriodicalIF":4.2,"publicationDate":"2026-10-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149259587","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Avian activity alters the speciation and coupling of inorganic sulfur and reactive iron in wetland sediments.","authors":"Zhaoran Li, Junchao Gao, Yaoting Guan, Zheng Wang, Shenwei Cheng, Yanqing Sheng","doi":"10.1039/d6em00496b","DOIUrl":"10.1039/d6em00496b","url":null,"abstract":"<p><p>Avian activity introduces exogenous organic matter into sediments <i>via</i> excreta, profoundly influencing the cycling of key elements such as sulfur and iron. However, its impact on sulfur-iron coupling processes and associated environmental effects remains unclear. This study was conducted in the Bird Paradise National Wetland Park to analyze the vertical distribution and coupling relationship of sulfur and iron. Results showed notable differences in the vertical distribution of inorganic sulfur and reactive iron in sediment cores from the high-bird-density area (X1) and the low-bird-density area (X2). The pronounced enrichment of Acid-Volatile Sulfide (AVS) in core X1 may be associated with enhanced sulfate reduction driven by labile organic matter from avian guano. However, the rapid accumulation and aging of AVS may have inhibited the conversion of AVS into pyrite (chromium-reducible sulfur nearly stagnated at 25-40 cm), shifting the sulfur-iron cycle from \"progressive pyritization\" to \"short-term AVS accumulation and long-term suppressed pyritization\". This shift weakened the buffering capacity of reactive iron against sulfide (a 12.2% decrease relative to X2 core), reduced the sediment's resilience to sulfide impacts, and increased potential ecological risks. These findings provide an important reference for the ecological conservation and environmental management of bird habitats.</p>","PeriodicalId":74,"journal":{"name":"Environmental Science: Processes & Impacts","volume":" ","pages":"2602-2611"},"PeriodicalIF":4.2,"publicationDate":"2026-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149011730","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}