九龙江流域土壤稀土元素分布特征及控制因素  

Distribution and Controlling Factors of Soil Rare Earth Elements in Jiulongjiang River Catchment

作　　者：张倩[1] 韩贵琳[2] ZHANG Qian;HAH Gui-lin(Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences,Beijing 100101,China;Institute of Earth Sciences,China University of Geosciences(Beijing),Beijing 100083,China)

机构地区：[1]中国科学院地理科学与资源研究所,北京100101 [2]中国地质大学(北京),北京100083

出　　处：《长江流域资源与环境》2022年第7期1494-1502,共9页Resources and Environment in the Yangtze Basin

基　　金：国家自然科学基金(41325010,41661144029)。

摘　　要：选取九龙江流域3种土壤(红壤、黄壤和赤红壤)的剖面为研究对象,研究稀土元素分布特征及垂向变化规律,并探讨其控制因素。结果显示,红壤和赤红壤剖面稀土元素总量(ΣREEs)在不同深度的顺序为:淋溶层<淀积层<半风化层,这与成土过程中发生的淋溶作用密切相关;黄壤剖面的淋溶层和淀积层的ΣREEs含量明显高于半风化层,主要与浅层土壤的农业活动有关。稀土元素配分模式显示,土壤剖面中Eu都均表现为明显负异常,源于母岩Eu负异常的继承和土壤氧化还原环境的变化,而黄壤、赤红壤剖面Ce表现为正异常,则可能由于风化成土过程的差异造成。九龙江流域土壤稀土元素的初始含量主要由成土母质决定,土壤矿物成分以及理化性质影响了土壤稀土元素的迁移和分异。土壤中含氧化物矿物组成多,粘粒含量高,有机质含量高,都有利于稀土元素的富集。Three soil profiles(yellow soil,red loam and red soil) from Jiulongjiang river catchment were selected to research.The results showed that the total rare earth elements(ΣREEs) of red soil and red loam were in the following order of different depths:leaching layer<sedimentary layer<semi-weathered layer,and the enrichment of REEs in semi-weathered layer was closely related to the leaching during pedogenesis.ΣREEs in leaching and sedimentary layers of yellow soil profile was significantly higher than that of the semi-weathered layer,which may be related to agricultural activities in shallow soil.The shale-normalized REEs pattern displayed obvious negative anomalies of Eu in all soil profiles,which may attribute to the inheritance of negative Eu anomalies in parent rock and the change of soil redox environment.Positive Ce anomalies in yellow soil and red soil profiles may be caused by the difference during weathering process.Initial soil REEs concentration in Jiulong river catchment is mainly determined by soil parent material,and soil mineral composition and physical/chemical properties affected the migration and fractionation of soil REEs.The higher composition of oxide minerals,higher clay content and organic matter content in soil are more conducive to the enrichment of REEs.

关 键 词：稀土元素 九龙江流域 土壤类型 

分 类 号：X53[环境科学与工程—环境工程]