摘要
以长江中游天鹅洲故道牛轭湖湿地为研究对象,研究了长江中游牛轭湖湿地内外侧C3、C5两个典型钻孔沉积物中砷、铁赋存形态和有机质组成差异,并结合内外侧沉积环境的差异,查明了牛轭湖湿地内外侧不同沉积环境中铁-有机质耦合作用对含水层沉积物中砷赋存形态的影响。结果表明:牛轭湖湿地外侧C3钻孔0~<10m浅层沉积物中含有更多的吸附在无定形铁氧化物和腐殖质类有机质上的强吸附态砷,牛轭湖湿地内侧C5钻孔沉积物中含有更多与硅酸盐铁结合的低活性砷;牛轭湖湿地外侧浅层沉积物中富含黏土矿物以及粒径偏细、风化程度较高的湖相沉积环境使得铁-有机质-砷共同富集,牛轭湖湿地内侧沉积物粒径偏粗、风化程度偏低的河流相沉积环境不利于活性砷和黏土矿物、有机质的赋存。
In this paper,taking the Tian-E-Zhou oxbow lake wetland in the middle reaches of the Yangtze River as the research object,the differences in arsenic and iron occurrence and organic matter composition of two typical borehole(C3 and C5)sediments in the inner and outer sides of the oxbow lake wetland were studied,and the effects of iron-carbon coupling on arsenic occurrence in the different sedimentary environments of the inner and outer sides of the oxbow lake in the Tian-E-Zhou wetland were revealed by combining the differences in the sedimentary environment of the inner and outer sides of the Tian-E-Zhou oxbow lake wetland.This study finds that the shallow sediments of borehole C3(0~<10 m)on the outer side of oxbow lake wetland contain more arsenic strongly adsorbed on amorphous iron oxides and humus organic matter,and the inner borehole C5 sediments contain more arsenic bound to iron silicate which is unreactive.The lacustrine sedimentary environment with fine particle size and high weathering degree of the shallow sediments on the outer side of the oxbow lake wetland enriches clay minerals and As-Fe-OM,while the fluvial sedimentary environment with coarse particle size and low weathering degree on the inner side of the oxbow lake wetland is not conducive to the enrichment of reactive arsenic,clay minerals and organic matter.
作者
李门楼
金戈
李甜
徐泽龙
汪倩
LI Menlou;JIN Ge;LI Tian;XU Zelong;WANG Qian(Institute of Education,China University of Geosciences(Wuhan),Wuhan 430074,China;College of Earth Sciences,Chengdu University of Technology,Chengdu 610059,China;Institute of Geological Survey,China University of Geosciences(Wuhan),Wuhan 430074,China;School of Environmental Studies,China University of Geosciences(Wuhan),Wuhan 430078,China)
出处
《安全与环境工程》
CAS
CSCD
2024年第1期182-195,共14页
Safety and Environmental Engineering
基金
国家自然科学基金面上项目(41977174)。
关键词
长江中游
牛轭湖湿地
沉积物
砷形态
铁氧化物
有机质
middle reaches of the Yangtze River
oxbow lake wetland
sediment
arsenic speciation
iron ox-ide
organic matter
