Iron-modified biochar(FeOS)is known to be effective at immobilization of arsenic(As)in soils.A pot experiment was conducted to investigate the effects of FeOS on As availability and ttransportation in the soil-rice sy...Iron-modified biochar(FeOS)is known to be effective at immobilization of arsenic(As)in soils.A pot experiment was conducted to investigate the effects of FeOS on As availability and ttransportation in the soil-rice system at different growth stages of rice with different pollution levels.The results showed that Fe concentration decreased and As concentration increased in paddy soils with the FeOS addition,especially in 120 mg/kg As treatment,the As concentration decreased by 16.46%and 30.56%at the maturity stage with 0.5%and 1%FeOS additions,respectively.Compared with the control,the application of FeOS reduced the arsenic content in rice tissues and increased the biomass,with the root biomass increased by 12.68%and the shoot biomass was increased by 8.94%with the addition of 1%FeOS.This may be related to the promotion of iron plaque formation and the transformation of microbial community structure in FeOS treatments,in accordance with the result of gene abundance and Fe/As contents of iron plaque in the study.This study is expected to provide further support and theoretical basis for the application of FeOS in the remediation of As contaminated paddy soil.展开更多
Atmospheric iron has crucial effects on biogeochemical cycles,atmospheric processing,global climate,and human health.In this study,atmospheric dustfall samples were collected from six functional areas in Xi'an,Chi...Atmospheric iron has crucial effects on biogeochemical cycles,atmospheric processing,global climate,and human health.In this study,atmospheric dustfall samples were collected from six functional areas in Xi'an,China,from 2020 to 2021.The spatiotemporal distributions and deposition fluxes of total and water-soluble(ws)Fe as well as the speciation and potential sources of ws-Fe were characterized.Industrial areas had the highest concentrations of total Fe and ws-Fe,which were mainly due to copious emissions of heavy metals during manufacturing.The total Fe concentrations peaked in spring,primarily due to the substantial input of crustal dust,which also led to the lowest Fe solubility in this season.By contrast,the highest levels of ws-Fe occurred during winter due to an increase in biomass combustion.Among the water-soluble forms,ws-Fe(II)was dominant and accounted for 74.8%of the total amount of ws-Fe.Crustal dust was the main contributor to total Fe,whereas biomass burning primarily contributed to peak ws-Fe concentrations.The average total and ws-Fe deposition fluxes in Xi'an were the highest in spring and lowest in autumn,which were related to the distributions of the dustfall deposition fluxes and their Fe contents during these periods.Our study provided a broader and comprehensive understanding of atmospheric iron deposition in Chinese urban area,which is of positive significance for understanding atmospheric chemistry and global climate change.展开更多
基金Project(2019YFC1803601)supported by the National Key Research and Development Program of ChinaProject(41771512)supported by the National Natural Science Foundation of ChinaProject(2018RS3004)supported by Hunan Science&Technology Innovation Program,China。
文摘Iron-modified biochar(FeOS)is known to be effective at immobilization of arsenic(As)in soils.A pot experiment was conducted to investigate the effects of FeOS on As availability and ttransportation in the soil-rice system at different growth stages of rice with different pollution levels.The results showed that Fe concentration decreased and As concentration increased in paddy soils with the FeOS addition,especially in 120 mg/kg As treatment,the As concentration decreased by 16.46%and 30.56%at the maturity stage with 0.5%and 1%FeOS additions,respectively.Compared with the control,the application of FeOS reduced the arsenic content in rice tissues and increased the biomass,with the root biomass increased by 12.68%and the shoot biomass was increased by 8.94%with the addition of 1%FeOS.This may be related to the promotion of iron plaque formation and the transformation of microbial community structure in FeOS treatments,in accordance with the result of gene abundance and Fe/As contents of iron plaque in the study.This study is expected to provide further support and theoretical basis for the application of FeOS in the remediation of As contaminated paddy soil.
基金the National Key R&D of China(grant No.2022YFF0802502)the State Key Laboratory of Loess and Quaternary National Key R&D of China Geology,Institute of Earth Environment,CAS(grant No.SKLLQG2014).
文摘Atmospheric iron has crucial effects on biogeochemical cycles,atmospheric processing,global climate,and human health.In this study,atmospheric dustfall samples were collected from six functional areas in Xi'an,China,from 2020 to 2021.The spatiotemporal distributions and deposition fluxes of total and water-soluble(ws)Fe as well as the speciation and potential sources of ws-Fe were characterized.Industrial areas had the highest concentrations of total Fe and ws-Fe,which were mainly due to copious emissions of heavy metals during manufacturing.The total Fe concentrations peaked in spring,primarily due to the substantial input of crustal dust,which also led to the lowest Fe solubility in this season.By contrast,the highest levels of ws-Fe occurred during winter due to an increase in biomass combustion.Among the water-soluble forms,ws-Fe(II)was dominant and accounted for 74.8%of the total amount of ws-Fe.Crustal dust was the main contributor to total Fe,whereas biomass burning primarily contributed to peak ws-Fe concentrations.The average total and ws-Fe deposition fluxes in Xi'an were the highest in spring and lowest in autumn,which were related to the distributions of the dustfall deposition fluxes and their Fe contents during these periods.Our study provided a broader and comprehensive understanding of atmospheric iron deposition in Chinese urban area,which is of positive significance for understanding atmospheric chemistry and global climate change.
