Article
Microbiology
Nicole Dopffel, James Jamieson, Casey Bryce, Prachi Joshi, Muammar Mansor, Adam Siade, Henning Prommer, Andreas Kappler
Summary: Through cultivation experiments and biogeochemical modeling analysis, we found that below 30 degrees Celsius, biologically driven Fe(II) oxidation largely dominates overall Fe(II) oxidation, while abiotic Fe(II) oxidation by nitrite plays a less significant role.
FEMS MICROBIOLOGY ECOLOGY
(2021)
Article
Geochemistry & Geophysics
Guoyong Huang, Xiaonan Wang, Dandan Pan, Guang Yang, Ruilin Zhong, Rumiao Niu, Bingqing Xia, Kuan Cheng, Tongxu Liu, Xiaomin Li
Summary: This study investigated the immobilization of cadmium (Cd) during nitrate-reducing Fe(II) oxidation (NRFO) and its impacts on the process. The results showed that higher initial Cd concentration led to a higher amount of Cd immobilized in precipitates but inhibited nitrate reduction, acetate metabolism, and cell growth. Cd had a minimal effect on Fe(II) oxidation during NRFO but slowed down the mineral transformation. Cd was found to be strongly co-localized with Fe on the surface of bacterial cells. Cd immobilization experiments indicated that both bacterial cells and secondary minerals were important for Cd immobilization. The findings provide important insights into the behavior and interactions of Cd during the NRFO process.
Article
Biology
Kuan Cheng, Han Li, Xiu Yuan, Yunlu Yin, Dandan Chen, Ying Wang, Xiaomin Li, Guojun Chen, Fangbai Li, Chao Peng, Yundang Wu, Tongxu Liu
Summary: This study examined the impact of hematite on nitrate-reducing Fe(II) oxidizing (NRFO) bacteria and found that hematite can enhance the reduction of nitrate by bacteria and mitigate cell encrustation. By acting as nucleation sites for cell encrustation reduction and catalyzing the biological and chemical oxidation of Fe(II), hematite promotes the activity of NRFO bacteria.
Article
Environmental Sciences
Jianghanyang Li, Perry Davy, Mike Harvey, Tanya Katzman, Tamsin Mitchell, Greg Michalski
Summary: This study analyzed the nitrogen isotopic composition of nitrate aerosols collected at Baring Head, New Zealand, and found significant seasonal variations, with lower values in the summer and higher values in the winter. The study also quantified isotopic fractionations during various oxidation processes of NOx, attributing the seasonal variations to the oxidation pathways of NO2. The overall isotopic fractionation factors were found to be lower in the summer and higher in the winter.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Geochemistry & Geophysics
Guojun Chen, Wenqi Zhao, Yang Yang, Dandan Chen, Ying Wang, Fangbai Li, Zhuyu Zhao, Fang Cao, Tongxu Liu
Summary: Chemodenitrification between Fe(II) and nitrite, a crucial nitrogen cycling pathway, is influenced by ambient temperatures. This study analyzed dual N-O isotope fractionation to investigate the temperature-dependent reactions and found that nitrite reduction rates and N2O production increased with temperature. Different secondary minerals were identified at varying temperatures, and the isotope fractionation ratios of O to N were affected by temperature change, stressing the importance of considering temperature effects in dual NO isotope data analysis.
Article
Agronomy
Chen-Chi Tsai, Yu-Fang Chang
Summary: The study showed that a 5% biochar application rate significantly reduced inorganic nitrogen levels in soil, with different types of biochar affecting nitrogen concentrations differently. Different soil types exhibited similar trends in reducing ammonium and nitrate levels after biochar application.
Review
Microbiology
Suyan Pang, Ning Li, Huan Luo, Xiaonan Luo, Tong Shen, Yanan Yang, Jin Jiang
Summary: This paper provides a systematic summary of the important reactions, microbial biodiversity, and environmental factors influencing the reaction rate in Fe-driven biological nitrogen removal technology. It also presents the current application advances and typical cases in wastewater treatment.
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Engineering, Environmental
Dandan Chen, Kuan Cheng, Tongxu Liu, Guojun Chen, Andreas Kappler, Xiaomin Li, Raymond Jianxiong Zeng, Yang Yang, Fujun Yue, Shiwen Hu, Fang Cao, Fangbai Li
Summary: This study demonstrates that dual N-O isotopes and kinetic modeling can be used to distinguish biological and chemical processes during microbially mediated NRFO. The main nitrate reductase in Acidovorax sp. strain BoFeN1 was found to be membrane-bound dissimilatory nitrate reductase (Nar). N-O isotopes can be used to differentiate between chemical and biological reactions, and chemodenitrification plays a more important role than biological reactions during the coupled process.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Microbiology
Anna-Neva Visser, Scott D. D. Wankel, Claudia Frey, Andreas Kappler, Moritz F. F. Lehmann
Summary: In this study, the effect of different organic substrates (short-chained organic acids) and the presence/absence of Fe(II) on nitrogen and oxygen isotope fractionation dynamics during nitrate and nitrite reduction were investigated. The results showed that the isotope effects obtained under heterotrophic and mixotrophic growth conditions were very similar and consistent with previous studies, indicating a lack of distinct differences caused by organic substrates and Fe(II).
FRONTIERS IN MICROBIOLOGY
(2022)
Article
Geochemistry & Geophysics
Xin Wang, Naomi S. Wells, Wei Xiao, Jessica L. Hamilton, Adele M. Jones, Richard N. Collins
Summary: The kinetics and stable isotopic fractionation of nitrate (NO3-) reduction in Fe(II)/Fe(III) homogeneous/heterogeneous systems were investigated. The reduction of NO3- was only significant in the presence of layered double hydroxide green rust (GR) minerals. The study provides insight into the importance of GR minerals in NO3- reduction and the potential use of stable isotopic fractionation analyses in distinguishing abiotic anoxic reactions from anaerobic bacterial NO3- reduction processes.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Engineering, Environmental
Jialin Chen, Ruina Zhang, Dong Chen, Jianyong Liu, Shanping Chen
Summary: The UV-enhanced generation of CO radical in the Fe(III)-oxalate system improves nitrate reduction to nitrogen with increased product selectivity. pH plays a key role in the NO reduction process, and higher concentrations of Fe(III) and oxalate promote NO3- removal and N-2 production.
JOURNAL OF WATER PROCESS ENGINEERING
(2021)
Review
Chemistry, Multidisciplinary
Xiaoxuan Yang, Shreya Mukherjee, Thomas O'Carroll, Yang Hou, Meenesh R. Singh, Joseph A. Gauthier, Gang Wu
Summary: Unrestrained anthropogenic activities disrupt the global natural nitrogen cycle, leading to energy and environmental issues. Electrocatalytic nitrogen transformation offers a feasible and promising strategy for a sustainable nitrogen economy. By synergistically combining multiple nitrogen reactions, efficient renewable energy storage and conversion, nitrogen balance restoration, and environmental crisis remediation can be achieved.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Geochemistry & Geophysics
Colin Ferrari, Eleonore Resongles, Marina Hery, Angelique Desoeuvre, Remi Freydier, Sophie Delpoux, Odile Bruneel, Corinne Casiot
Summary: The oxidation of antimonite to antimonate plays a crucial role in controlling the mobility of antimony in aquatic systems. This study investigates the fractionation of antimony isotopes during the oxidation process under mining-relevant concentrations. The results show that the fractionation of antimony isotopes is influenced by experimental conditions and reaction pathways. While antimony isotopes have the potential to serve as process tracers in water, further research and comparison with natural systems are needed.
Article
Geochemistry & Geophysics
Panpan Xie, Shifeng Dai, James C. Hower, Victor P. Nechaev, David French, Ian T. Graham, Xibo Wang, Lei Zhao, Jianping Zuo
Summary: Coals containing ammonium-bearing aluminosilicates are rich in critical elements. The nitrogen in these minerals likely originates from the decomposition of organic matter in coals under increased geothermal gradient from intrusions or hydrothermal fluids. The isotopic composition of nitrogen in the minerals and coals provides valuable insights into their formation and sources of critical elements.
Article
Biotechnology & Applied Microbiology
Jianrong Huang, Mingxian Han, Jian Yang, Andreas Kappler, Hongchen Jiang
Summary: NRFeOx microorganisms are widely distributed and play an important role in iron transformation, nitrate, and heavy metal removal in various environments. However, their identity and activity under hypersaline conditions are still unknown. In this study, we analyzed the abundance and community compositions of NRFeOx microorganisms from five lake sediments with different salinities. The results showed that the abundance of NRFeOx microorganisms decreased with increasing salinity, and the community compositions varied among different lakes and were closely related to lake salinity.
APPLIED AND ENVIRONMENTAL MICROBIOLOGY
(2022)
Article
Biology
Kuan Cheng, Han Li, Xiu Yuan, Yunlu Yin, Dandan Chen, Ying Wang, Xiaomin Li, Guojun Chen, Fangbai Li, Chao Peng, Yundang Wu, Tongxu Liu
Summary: This study examined the impact of hematite on nitrate-reducing Fe(II) oxidizing (NRFO) bacteria and found that hematite can enhance the reduction of nitrate by bacteria and mitigate cell encrustation. By acting as nucleation sites for cell encrustation reduction and catalyzing the biological and chemical oxidation of Fe(II), hematite promotes the activity of NRFO bacteria.
Article
Environmental Sciences
Wenting Chi, Yang Yang, Ke Zhang, Pei Wang, Yanhong Du, Xiaomin Li, Yan Sun, Tongxu Liu, Fangbai Li
Summary: Seawater intrusion can pose environmental risks to paddy soils around estuaries, with the impacts on the availability of heavy metals still being unclear. This study found that increasing salinity levels led to higher release of Cd from soils, indicating that Cd competition by cations and complexation by anions dominated the release rather than pH. Additionally, the availability of Cd in paddy soil was found to be enhanced with increasing salinity levels, especially during drainage, indicating the importance of high salinity in influencing Cd availability in paddy soil.
Article
Environmental Sciences
Yingmei Huang, Fangbai Li, Jicai Yi, Huili Yan, Zhenyan He, Xiaomin Li
Summary: In this study, rice seedlings were exposed to different concentrations of mercury to investigate its effects on rice roots and shoots. It was found that mercury accumulated mainly in the roots, and higher concentrations of mercury increased the root-to-shoot translocation factors, resulting in elevated mercury concentrations in the shoots. Higher concentrations of mercury also inhibited root growth and reduced photosynthesis capacity in the leaves. Transcriptome sequencing analysis showed that genes associated with glutathione metabolism, amino acid biosynthesis, and secondary metabolite metabolism played significant roles in mercury accumulation by the rice plants.
Article
Engineering, Environmental
Yundang Wu, Xiao Zhu, Xinxin Wang, Zhixin Lin, John R. Reinfelder, Fangbai Li, Tongxu Liu
Summary: A new electron shuttling pathway was discovered in Shewanella oneidensis MR-1 using the lipophilic electron mediator resazurin. This pathway is independent of the Mtr pathway and relies on the involvement of FccA, CctA, and CymA. The findings provide new insights into the role of exogenous electron mediators in electron shuttling in natural and engineered biogeochemical systems.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Environmental Sciences
Yufan Zhang, Xiangqin Wang, Yang Yang, Yingmei Huang, Xiaomin Li, Shiwen Hu, Kexue Liu, Yan Pang, Tongxu Liu, Fangbai Li
Summary: In order to assess the risks and develop remediation strategies for mercury-contaminated soils in paddy fields, understanding the mechanisms of mercury transformation and migration is crucial. This study investigated the changes in mercury fractions in a spiked acidic paddy soil under anoxic and oxic conditions, and established a kinetic model to quantitatively estimate the transformation processes. The results provided new insights into the exogenous mercury transformation processes and could be useful in predicting mercury availability in periodically flooded acidic paddy fields.
ENVIRONMENTAL POLLUTION
(2023)
Article
Agriculture, Multidisciplinary
Xiangqin Wang, Yanhong Du, Jing Zhou, Guanhong Chen, Xiaomin Li, Liping Fang, Fangbai Li, Yuzhen Yuan, Yang Yang, Fei Dou
Summary: The bioavailability of arsenic in paddy soil-rice systems is affected by ammonium fertilization, but the mechanisms controlling As transformation are not fully understood. This study found that urea and ammonium bicarbonate fertilizers significantly increased As(III) concentration in porewater, bioavailable As in rhizosphere soil, and the relative abundance of arrA and arsM genes. Moreover, the expression of As transporter genes in rice roots was upregulated, leading to increased translocation efficiency of As(III) from roots to brown rice. Therefore, attention should be paid to As-contaminated paddy fields with ammonium fertilization.
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
(2023)
Article
Engineering, Environmental
Kaiyi Huang, Yang Yang, Hansha Lu, Shiwen Hu, Guojun Chen, Yanhong Du, Tongxu Liu, Xiaomin Li, Fangbai Li
Summary: This study investigates the transformation processes of nickel in paddy soils under anoxic and oxic conditions. The results show that under anoxic conditions, complexation with soil organic matter dominates nickel immobilization, while under oxic conditions, organic matter and Fe-Mn oxides contribute similarly to nickel release.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Environmental Sciences
Mi Feng, Yanhong Du, Xiaomin Li, Fangbai Li, Jiangtao Qiao, Gongning Chen, Yingmei Huang
Summary: This study investigated the universality and characteristics of nitrate reduction coupled with arsenic (As) oxidation in paddy soils. The results showed that nitrate effectively transformed toxic As(III) into less toxic and nonlabile As(V), and the addition of nitrate increased the abundance of 16S rRNA and As(III) oxidase genes in the soils. Metagenomic analysis also identified several putative novel nitrate-dependent As(III)-oxidizing bacteria.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Environmental Sciences
Songxiong Zhong, Xiaomin Li, Fangbai Li, Dandan Pan, Tongxu Liu, Yingmei Huang, Qi Wang, Haoming Yin, Fang Huang
Summary: The filling of rice grains is a critical period for the accumulation of excessive cadmium (Cd), but uncertainties still exist in identifying the sources of Cd enrichment in grains. In this study, pot experiments were conducted to investigate the transport and redistribution of Cd to grains during drainage and flooding. The results showed that Cd isotopes in rice plants were lighter than those in soil solutions but heavier than those in Fe plaques. Fe plaque was identified as a potential source of Cd in rice, particularly during flooding at the grain filling stage. Drainage during grain filling led to a negative fractionation of Cd from various parts of the rice plant, while flooding facilitated the transport of Cd from leaves, rachises, and husks to grains. These findings highlight the importance of ligands and transporters genes, along with isotope fractionation, in tracking the source of Cd transported to rice grains.
SCIENCE OF THE TOTAL ENVIRONMENT
(2023)
Article
Geochemistry & Geophysics
Guoyong Huang, Xiaonan Wang, Dandan Pan, Guang Yang, Ruilin Zhong, Rumiao Niu, Bingqing Xia, Kuan Cheng, Tongxu Liu, Xiaomin Li
Summary: This study investigated the immobilization of cadmium (Cd) during nitrate-reducing Fe(II) oxidation (NRFO) and its impacts on the process. The results showed that higher initial Cd concentration led to a higher amount of Cd immobilized in precipitates but inhibited nitrate reduction, acetate metabolism, and cell growth. Cd had a minimal effect on Fe(II) oxidation during NRFO but slowed down the mineral transformation. Cd was found to be strongly co-localized with Fe on the surface of bacterial cells. Cd immobilization experiments indicated that both bacterial cells and secondary minerals were important for Cd immobilization. The findings provide important insights into the behavior and interactions of Cd during the NRFO process.
Article
Engineering, Environmental
Dandan Chen, Kuan Cheng, Tongxu Liu, Guojun Chen, Andreas Kappler, Xiaomin Li, Raymond Jianxiong Zeng, Yang Yang, Fujun Yue, Shiwen Hu, Fang Cao, Fangbai Li
Summary: This study demonstrates that dual N-O isotopes and kinetic modeling can be used to distinguish biological and chemical processes during microbially mediated NRFO. The main nitrate reductase in Acidovorax sp. strain BoFeN1 was found to be membrane-bound dissimilatory nitrate reductase (Nar). N-O isotopes can be used to differentiate between chemical and biological reactions, and chemodenitrification plays a more important role than biological reactions during the coupled process.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Songxiong Zhong, Liping Fang, Xiaomin Li, Tongxu Liu, Pei Wang, Ruichuan Gao, Guojun Chen, Haoming Yin, Yang Yang, Fang Huang, Fangbai Li
Summary: This study investigates the influence of chloride and sulfate ions on the transport of cadmium (Cd) in the soil-rice system. The results show that chloride and sulfate ions increase the concentration of Cd in the soil solution, Fe plaque, and rice plants, facilitating the mobility of Cd isotopes and contributing to Cd immobilization in the Fe plaque and uptake into roots. The findings provide insights into the role of anions in Cd migration and transformation in the soil-rice system.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2023)
Article
Engineering, Environmental
Wenting Chi, Guojun Chen, Shiwen Hu, Xiaomin Li, Kuan Cheng, Qi Wang, Bingqing Xia, Yang Yang, Yibing Ma, Tongxu Liu
Summary: Paddy fields located around estuaries face the issue of seawater intrusion, and the impact of salinity levels on Cd accumulation in rice grains is still unclear. Pot experiments were conducted to investigate the effects of different salinity levels on Cd availability and uptake by rice plants. The results showed that higher salinity levels increased Cd availability and uptake in rice roots and grains, mainly due to competition for binding sites by cations and the formation of Cd complexation with anions. The study highlights the importance of considering food safety in rice cultivation near estuaries.
JOURNAL OF HAZARDOUS MATERIALS
(2023)
Article
Engineering, Environmental
Zebin Hong, Shiwen Hu, Yang Yang, Ziwei Deng, Xiaomin Li, Tongxu Liu, Fangbai Li
Summary: Through investigating the variations of arsenic (As) in mine wastewater, it was found that under flooded condition, As(III) can be immobilized while As(V) can be activated in paddy soil, which influences the mobility of As. During drainage, available As is mainly immobilized by Fe oxyhydroxides and humic substances, and adsorbed As(III) is oxidized. These results provide an estimation pathway for the impacts of key biogeochemical cycles on exogenous As species under a redox-alternating condition.
Article
Environmental Sciences
Hansha Lu, Yang Yang, Kaiyi Huang, Guoyong Huang, Shiwen Hu, Dandan Pan, Tongxu Liu, Xiaomin Li
Summary: This study investigates the transformation of lead (Pb) in acidic soil under alternating anoxic-oxic conditions using a kinetic model. The results suggest that under anoxic conditions, Pb is gradually transferred to fulvic complex, Fe-Mn oxides bound, and sulfides bound Pb, while under oxic conditions, the fulvic complex Pb further increases. Phosphorus plays a more important role than organic matter in Pb immobilization under anoxic conditions, while the phosphates, Fe-Mn oxides, and sulfides immobilized Pb is slowly released and then complexed by fulvic acids during the re-immobilization of dissolved organic matter in soil under oxic conditions.
ENVIRONMENTAL POLLUTION
(2023)
Article
Geochemistry & Geophysics
Zhen-Min Ge, Xiao-Long Huang, Wei Xie, Tobias W. Hofig, Fan Yang, Yang Yu, S. Khogenkumar Singh
Summary: The mantle source composition of the nascent oceanic crust in the central part of the Gulf of California has been investigated using basaltic glass samples. These samples show trace element patterns similar to enriched mid-ocean ridge basalts, suggesting that the nascent oceanic crust in the Guaymas Basin might be generated through partial melting of a depleted mantle source metasomatized by subducted slab materials.
Article
Geochemistry & Geophysics
Jean-Michel Brazier, Katja E. Goetschl, Martin Dietzel, Vasileios Mavromatis
Summary: This study estimated the distribution coefficient of Zn2+ between calcite/aragonite and reactive fluids and found that the growth rate strongly influences D-Zn(2+) in both minerals. Additionally, a linear correlation was found between D-Zn(2+) and the saturation degree of the reactive fluid.
Article
Geochemistry & Geophysics
Ming Lei, Michele Lustrino, Jifeng Xu, Zhiqiang Kang, Zhengfu Guo, Jianlin Chen
Summary: This study presents a comprehensive geochronological, mineralogical, and geochemical analysis of olivine leucitites in the Maiga area of southern Tibet, suggesting that these rocks originate from a carbonated peridotite mantle source and highlighting the possibility of carbonates being recycled deep into the mantle during continental subduction.
Article
Geochemistry & Geophysics
Yuntao Ye, Xiaomei Wang, Huajian Wang, Haifeng Fan, Zhigang Chen, Qingjun Guo, Ziteng Wang, Chaodong Wu, Donald E. Canfield, Shuichang Zhang
Summary: Phosphorus is an essential element for life and its cycle in the ocean is closely connected with the carbon and oxygen cycles. The study of phosphate oxygen isotopes can provide insights into various reactions related to phosphorus. By analyzing carbonate fluorapatite samples from the Mesoproterozoic Era in North China, it was found that the oxygen isotope values were lower compared to modern samples, indicating a warmer climate during that time period and a potential reason for the scarcity of phosphorite.
Article
Geochemistry & Geophysics
Vincent Busigny, Oanez Lebeau, Didier Jezeduel, Carine Chaduteau, Sean Crowe, Magali Ader
Summary: This study conducted high-precision Mo isotope research on hydrothermal metal sulfides from a porphyry copper deposit in Southwest China and found that different stages of mineralization have distinct Mo isotope compositions, providing valuable insights into the behavior of Mo isotopes in magmatic-hydrothermal systems.
Article
Geochemistry & Geophysics
Min Ji, Xiao-Ying Gao, Yong-Fei Zheng, Bing Gong
Summary: The study examines the anatectic mechanisms in the Himalayan orogen, finding that pressure and temperature control the reaction, while water content mainly affects the solid-phase composition. Dehydration and hydration melting likely occur at different depths in the crust. This research provides important insights into the melting processes in collisional orogens.
