Simultaneous measurement of aqueous redox-sensitive elements and their species across the soil-water interface  

作　　者：Zhao-Feng Yuan Williamson Gustave Raju Sekar Jonathan Bridge Jia-Yue Wang Wei-Jia Feng Bin Guo Zheng Chen 

机构地区：[1]Department of Health and Environmental Sciences,Xi’an Jiaotong-Liverpool University,Jiangsu 215123,China [2]Department of Environmental Science,University of Liverpool,Liverpool L697ZX,UK [3]Department of Plant Science,Tarim University,Xinjiang 843300,China [4]Chemistry,Environmental&Life Sciences,University of The Bahamas,Nassau,Bahamas [5]Department of Biological Sciences,Xi’an Jiaotong-Liverpool University,Jiangsu 215123,China [6]Department of Natural and Built Environment,Sheffield Hallam University,Sheffield S11WB,UK [7]Institute of Environment,Resource,Soil and Fertilizer,Zhejiang Academy of Agricultural Sciences,Zhejiang 310021,China

出　　处：《Journal of Environmental Sciences》2021年第4期1-10,共10页环境科学学报（英文版）

基　　金：supported by the National Science Foundation of China(Nos.41977320,41571305);Key Programme Special Fund of XJTLU(No.KSF-A-20)。

摘　　要：The redox-sensitive elements,such as iron,manganese,sulfur,phosphorus,and arsenic,shift their speciation every millimeter(mm)across the soil-water interface in the flooded soil environments.Monitoring of element speciation at this high-resolution(HR)within the SWI is still difficult.The key challenge lies in obtaining sufficient porewater samples at specific locations along the soil gradient for downstream analysis.Here with an optimized inductively coupled plasma mass spectrometry(ICP-MS)method and a HR porewater sampler,we demonstrate mm-scale element profiles mapping across the SWI in paddy soils.Highconcentrations of iron and manganese(>10 mg/L)were measured by ICP-MS in an extended dynamic range mode to avoid signal overflow.The iron profile along the SWI generated by the ICP-MS method showed no significant difference(p<0.05)compared to that measured independently using a colorimetric method.Furthermore,four arsenic(arsenite,arsenate,monomethylarsonic and dimethylarsinic acid),two phosphorus(phosphite and phosphate)and two sulfur(sulfide and sulfate)species were separated in 10 min by ion chromatography-ICP-MS with the NH_(4)HCO_(3)mobile phase.We verified the technique using paddy soils collected from the field,and present the mm-scale profiles of iron,manganese,and arsenic,phosphorus,sulfur species(relative standard deviation<8%).The technique developed in this study will significantly promote the measurement throughput in limited samples(e.g.100μL)collected by HR samplers,which would greatly facilitate redox-sensitive elements biogeochemical cycling in saturated soils.

关 键 词：POREWATER Soil-water interface ARSENIC Iron SULFUR SPECIES 

分 类 号：X830[环境科学与工程—环境工程]