Biochar-supported zero-valent iron enhanced arsenic immobilization in a paddy soil:the role of soil organic matter  

作　　者：Shengsen Wang Wenjing Li Chengyu Ding Jian Zhang Ni Zhang Yuncong CLi Bin Gao Bing Wang Xiaozhi Wang 

机构地区：[1]College of Environmental Science and Engineering,Yangzhou University,Yangzhou 225127,China. [2]Key Laboratory of Arable Land Quality Monitoring and Evaluation,Ministry of Agriculture and Rural Affairs,Yangzhou University,Yangzhou 225127,China. [3]Joint International Research Laboratory of Agriculture and Agri-Product Safety of Ministry of Education of China,Yangzhou University,Yangzhou 225127,Jiangsu,China [4]Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization,Nanjing,China. [5]Department of Soil,Water,Ecosystem Sciences,Tropical Research and Education Center,IFAS,University of Florida,Homestead,FL 33031,USA. [6]Department of Civil and Environmental Engineering,Rensselaer Polytechnic Institute,Troy,NY 12180,USA. [7]College of Resources and Environmental Engineering,Guizhou University,Guiyang 550025,China.

出　　处：《Biochar》2024年第1期487-500,共14页生物炭(英文)

基　　金：National Natural Science Foundation of China[Grant numbers 42277040,41977117,41977085];National Key Research and Development Program of China[Grant number 2021YFD1700800];Qing-Lan Project of Yangzhou University[2020];High-level Talent Support Plan of Yangzhou University[2019].

摘　　要：Arsenic(As)detoxification in polluted soils by iron-based materials can be mediated by the endogenous soil organic matter(SOM),nevertheless the mechanisms remain unclear.Herein,endogenous SOM in a paddy soil was substantially removed to understand its roles on As immobilization by biochar-supported zero-valent iron(ZVI/BC).The results demonstrated that ZVI/BC application significantly decreased As bioavailability by 64.2%compared with the control soil under the anaerobic condition.XPS and HR-TEM suggested As immobilization by ZVI/BC mainly invoked the formation of ternary complexes(i.e.,As-Fe-SOM).However,SOM depletion compromised the efficacy of ZVI/BC for As immobilization by 289.8%.This is likely because SOM depletion increased the fulvic acid and OH−contents in soils.Besides,ZVI/BC increased the proportion of As(III)in available As fraction,but SOM depletion altered the mechanisms associated with As(V)reduction.That is,As(V)reduction resulted from the reductive capacity of ZVI in the pristine soil,but the As(V)-reducing bacteria contributed greater to As(V)reduction in the SOM-depleted soil.Additionally,SOM depletion boosted the abundances of Fe(III)-and As(V)-reducing bacteria such as Bacillus and Ammoniphilus in soils,which enhanced the dissimilatory arsenate reduction.Thus,this work highlighted the importance of SOM in the remediation of As-contaminated soils by ZVI/BC.

关 键 词：Biochar-supported zero-valent iron Arsenic transformation As(V)-reducing bacteria Soil organic matter Paddy soil 

分 类 号：X70[环境科学与工程—环境工程]