{"title":"The effects and mechanism of organic matter degradation in river sediment driven by humic-reducing bacteria","authors":"","doi":"10.1016/j.jwpe.2024.106150","DOIUrl":null,"url":null,"abstract":"<div><p>The reduction of organic pollutants in sediments is essential for controlling the rebound of black-odor waterbodies. Humic-reducing bacteria are promising in the anaerobic remediation of river sediments. However, the material conditions and environmental factors influencing organic matter (OM) degraded by humic-reducing bacteria in river sediment remain unclear. In this study, humic-reducing bacteria agents (HRBs) were used to remediate sediments with different contamination levels. The result indicated that HRBs remove light fraction organic matter (LFOM) in sediment with a high active organic matter (ATOM) content and can remove heavy fraction organic matter (HFOM) in sediment with a high degree of humification. Correlation analysis showed that OM removal was significantly correlated with fluorescein diacetate (FDA) hydrolase activity (<em>R</em> = 0.89, <em>P</em> ≤ 0.01) and acidified volatile sulfides (AVS) content (<em>R</em> = 0.81, <em>P</em> ≤ 0.05), respectively. Combined analyses of changes in iron morphology and FDA hydrolase activity revealed that HRBs mediated the reduction process of iron minerals, leading to an increase in Fe(II) content in sediment. HFOM complexed with iron minerals was released and could be further decomposed and utilized by FDA hydrolases. In addition, the process of OM degraded by HRBs can induce the accumulation of Fe(II) and AVS. The work helps to understand the mechanism of OM degraded by HRBs in sediment and the applicable conditions for the effective removal of OM by HRBs to control the rebound of black-odor waterbodies caused by endogenous pollution.</p></div>","PeriodicalId":17528,"journal":{"name":"Journal of water process engineering","volume":null,"pages":null},"PeriodicalIF":6.3000,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of water process engineering","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2214714424013825","RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"ENGINEERING, CHEMICAL","Score":null,"Total":0}
引用次数: 0
Abstract
The reduction of organic pollutants in sediments is essential for controlling the rebound of black-odor waterbodies. Humic-reducing bacteria are promising in the anaerobic remediation of river sediments. However, the material conditions and environmental factors influencing organic matter (OM) degraded by humic-reducing bacteria in river sediment remain unclear. In this study, humic-reducing bacteria agents (HRBs) were used to remediate sediments with different contamination levels. The result indicated that HRBs remove light fraction organic matter (LFOM) in sediment with a high active organic matter (ATOM) content and can remove heavy fraction organic matter (HFOM) in sediment with a high degree of humification. Correlation analysis showed that OM removal was significantly correlated with fluorescein diacetate (FDA) hydrolase activity (R = 0.89, P ≤ 0.01) and acidified volatile sulfides (AVS) content (R = 0.81, P ≤ 0.05), respectively. Combined analyses of changes in iron morphology and FDA hydrolase activity revealed that HRBs mediated the reduction process of iron minerals, leading to an increase in Fe(II) content in sediment. HFOM complexed with iron minerals was released and could be further decomposed and utilized by FDA hydrolases. In addition, the process of OM degraded by HRBs can induce the accumulation of Fe(II) and AVS. The work helps to understand the mechanism of OM degraded by HRBs in sediment and the applicable conditions for the effective removal of OM by HRBs to control the rebound of black-odor waterbodies caused by endogenous pollution.
期刊介绍:
The Journal of Water Process Engineering aims to publish refereed, high-quality research papers with significant novelty and impact in all areas of the engineering of water and wastewater processing . Papers on advanced and novel treatment processes and technologies are particularly welcome. The Journal considers papers in areas such as nanotechnology and biotechnology applications in water, novel oxidation and separation processes, membrane processes (except those for desalination) , catalytic processes for the removal of water contaminants, sustainable processes, water reuse and recycling, water use and wastewater minimization, integrated/hybrid technology, process modeling of water treatment and novel treatment processes. Submissions on the subject of adsorbents, including standard measurements of adsorption kinetics and equilibrium will only be considered if there is a genuine case for novelty and contribution, for example highly novel, sustainable adsorbents and their use: papers on activated carbon-type materials derived from natural matter, or surfactant-modified clays and related minerals, would not fulfil this criterion. The Journal particularly welcomes contributions involving environmentally, economically and socially sustainable technology for water treatment, including those which are energy-efficient, with minimal or no chemical consumption, and capable of water recycling and reuse that minimizes the direct disposal of wastewater to the aquatic environment. Papers that describe novel ideas for solving issues related to water quality and availability are also welcome, as are those that show the transfer of techniques from other disciplines. The Journal will consider papers dealing with processes for various water matrices including drinking water (except desalination), domestic, urban and industrial wastewaters, in addition to their residues. It is expected that the journal will be of particular relevance to chemical and process engineers working in the field. The Journal welcomes Full Text papers, Short Communications, State-of-the-Art Reviews and Letters to Editors and Case Studies