Benthic biofilms as reservoirs of recalcitrant organic matter in freshwater reservoirs: insights from FT-ICR MS

IF 7.7 2区 环境科学与生态学 Q1 ENVIRONMENTAL SCIENCES
Ch. Tahir Mehmood , Yujian Dong , Huiyu Liu , Han Yu , Yan Wang , Yiwei Li , Yeyuan Xiao , Olivier Habimana
{"title":"Benthic biofilms as reservoirs of recalcitrant organic matter in freshwater reservoirs: insights from FT-ICR MS","authors":"Ch. Tahir Mehmood ,&nbsp;Yujian Dong ,&nbsp;Huiyu Liu ,&nbsp;Han Yu ,&nbsp;Yan Wang ,&nbsp;Yiwei Li ,&nbsp;Yeyuan Xiao ,&nbsp;Olivier Habimana","doi":"10.1016/j.envres.2025.122945","DOIUrl":null,"url":null,"abstract":"<div><div>Benthic biofilms play a significant role in influencing the composition and cycling of dissolved organic matter (DOM) in freshwater reservoirs. In this study, we characterized the molecular composition of DOM using direct injection Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (DI-FT-ICR MS), with complementary insights provided by three-dimensional Excitation-Emission Matrix (3D EEM) fluorescence spectroscopy, comparing samples from bulk water and biofilms across three reservoirs. Biofilm-associated DOM exhibited higher SUVA-254 and Aromaticity Index (AI-mod) values, indicating an enrichment of recalcitrant and humic substances. 3D EEM analysis showed a 35 % increase in humic-like substances within biofilms compared to bulk water, underscoring their role in stabilizing organic compounds. FT-ICR MS analyses demonstrated that classes of aromatic compounds, including condensed aromatics, exhibited a markedly higher prevalence within biofilms (25.9 %) in comparison to bulk water (18.5 %). Biofilms also encompassed a greater quantity of nitrogenous compounds, with CHON categories constituting 17.3 % of dissolved organic matter (DOM) in biofilms in contrast to 9.2 % in bulk aquatic environments, underscoring their significance in nutrient cycling. Conversely, sulfur-containing compounds (CHOS) were less abundant in benthic biofilm samples (6.4 %) than in corresponding bulk water (12.1 %), a difference potentially attributable to various processes including differential production, consumption, or diffusion. Furthermore, biofilms displayed a higher average molecular weight (476.3 m/z) and elevated Double Bond Equivalence (DBE) (14.45) compared to bulk water (454.1 m/z; 12.99), highlighting the greater complexity of biofilm-associated DOM. Significant alterations in the composition of microbial communities observed between bulk water and biofilms provide additional evidence of the functional role that biofilms play in the alterations of dissolved organic matter (DOM). These results emphasize the significance of benthic biofilms in stabilizing organic substances, which has a substantial effect on the well-being and administration of freshwater ecosystems.</div></div>","PeriodicalId":312,"journal":{"name":"Environmental Research","volume":"286 ","pages":"Article 122945"},"PeriodicalIF":7.7000,"publicationDate":"2025-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Environmental Research","FirstCategoryId":"93","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0013935125021978","RegionNum":2,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENVIRONMENTAL SCIENCES","Score":null,"Total":0}
引用次数: 0

Abstract

Benthic biofilms play a significant role in influencing the composition and cycling of dissolved organic matter (DOM) in freshwater reservoirs. In this study, we characterized the molecular composition of DOM using direct injection Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (DI-FT-ICR MS), with complementary insights provided by three-dimensional Excitation-Emission Matrix (3D EEM) fluorescence spectroscopy, comparing samples from bulk water and biofilms across three reservoirs. Biofilm-associated DOM exhibited higher SUVA-254 and Aromaticity Index (AI-mod) values, indicating an enrichment of recalcitrant and humic substances. 3D EEM analysis showed a 35 % increase in humic-like substances within biofilms compared to bulk water, underscoring their role in stabilizing organic compounds. FT-ICR MS analyses demonstrated that classes of aromatic compounds, including condensed aromatics, exhibited a markedly higher prevalence within biofilms (25.9 %) in comparison to bulk water (18.5 %). Biofilms also encompassed a greater quantity of nitrogenous compounds, with CHON categories constituting 17.3 % of dissolved organic matter (DOM) in biofilms in contrast to 9.2 % in bulk aquatic environments, underscoring their significance in nutrient cycling. Conversely, sulfur-containing compounds (CHOS) were less abundant in benthic biofilm samples (6.4 %) than in corresponding bulk water (12.1 %), a difference potentially attributable to various processes including differential production, consumption, or diffusion. Furthermore, biofilms displayed a higher average molecular weight (476.3 m/z) and elevated Double Bond Equivalence (DBE) (14.45) compared to bulk water (454.1 m/z; 12.99), highlighting the greater complexity of biofilm-associated DOM. Significant alterations in the composition of microbial communities observed between bulk water and biofilms provide additional evidence of the functional role that biofilms play in the alterations of dissolved organic matter (DOM). These results emphasize the significance of benthic biofilms in stabilizing organic substances, which has a substantial effect on the well-being and administration of freshwater ecosystems.
底栖生物膜作为淡水储层中顽固性有机物的储层:FT-ICR MS的见解。
底栖生物膜对淡水水库中溶解有机物(DOM)的组成和循环具有重要影响。在这项研究中,我们使用直接注射傅里叶变换离子回旋共振质谱(DI-FT-ICR MS)表征DOM的分子组成,并通过三维激发-发射矩阵(3D EEM)荧光光谱提供补充见解,比较了三个水库的大量水和生物膜样品。与生物膜相关的DOM表现出较高的SUVA-254和芳香指数(AI-mod)值,表明其含有丰富的难固性和腐殖质物质。3D EEM分析显示,与散装水相比,生物膜内腐殖质样物质增加了35%,强调了它们在稳定有机化合物方面的作用。FT-ICR质谱分析表明,芳香族化合物,包括凝聚芳香族化合物,在生物膜中的流行率(25.9%)明显高于散装水(18.5%)。生物膜还含有更多的氮化合物,CHON类在生物膜中占溶解有机物(DOM)的17.3%,而在散装水生环境中占9.2%,强调了它们在营养循环中的重要性。相反,含硫化合物(CHOS)在底栖生物膜样品中的含量(6.4%)低于相应的散装水(12.1%),这一差异可能归因于不同的过程,包括不同的生产、消耗或扩散。此外,与体积水(454.1 m/z; 12.99)相比,生物膜表现出更高的平均分子量(476.3 m/z)和更高的双键当量(DBE)(14.45),突出了生物膜相关DOM的更大复杂性。在散装水和生物膜之间观察到的微生物群落组成的显著变化为生物膜在溶解有机物(DOM)的改变中发挥的功能作用提供了额外的证据。这些结果强调了底栖生物膜在稳定有机物质方面的重要性,这对淡水生态系统的健康和管理具有重大影响。
本文章由计算机程序翻译,如有差异,请以英文原文为准。
求助全文
约1分钟内获得全文 求助全文
来源期刊
Environmental Research
Environmental Research 环境科学-公共卫生、环境卫生与职业卫生
CiteScore
12.60
自引率
8.40%
发文量
2480
审稿时长
4.7 months
期刊介绍: The Environmental Research journal presents a broad range of interdisciplinary research, focused on addressing worldwide environmental concerns and featuring innovative findings. Our publication strives to explore relevant anthropogenic issues across various environmental sectors, showcasing practical applications in real-life settings.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:604180095
Book学术官方微信