Arsenic,Iron and Organic Matter in Quaternary Aquifer Sediments from Western Hetao Basin,Inner Mongolia
Arsenic,Iron and Organic Matter in Quaternary Aquifer Sediments from Western Hetao Basin,Inner Mongolia作者机构:Geological SurveyChina University of GeosciencesWuhan 430074China Ningxia Institute of Geological SurveyYinchuan 750001China School of Environmental StudiesChina University of GeosciencesWuhan 430074China
出 版 物:《Journal of Earth Science》 (地球科学学刊(英文版))
年 卷 期:2017年第28卷第3期
页 面:473-483页
核心收录:
学科分类:083001[工学-环境科学] 0830[工学-环境科学与工程(可授工学、理学、农学学位)] 08[工学] 0708[理学-地球物理学] 0704[理学-天文学]
基 金:financially supported by the National Natural Science Foundation of China(No.41572226)
主 题:arsenic sediment organic matter Hetao Basin
摘 要:To investigate geochemical and mineralogical features of sediments from aquifers containing high levels of dissolved arsenic(As) in western Hetao Basin, Inner Mongolia, sediment samples were collected for XRD(X-ray diffraction), amorphous Fe/Mn oxides, and humic/fulvic acid analyses, in addition to As determination. In the study area, the total As contents in the sediments were in the range 5.3–28.8 mg/kg; while that associated with humic substances in the range 4–9 mg/kg, accounting for 26%–47% of the total As. The results of XRD analysis suggest that clay and silt contain certain small amounts of iron oxides minerals, such as ferrihydrite, hematite and goethite, whereas have higher As and Fe_2O_3 contents. Up to one third of As in the sediments could be extracted by ammonium oxalate, and high As contents were generally found in organic-rich clay or silty clay samples with high FA/HA ratio. As is strongly associated with humic substances and Fe oxyhydroxides, which may be the major sink and source of As in the aquifer sediments.