地质高背景区成土母岩对表土硒含量及其生物有效性的影响  

Effect of Pedogenic Rock on Soil Selenium and Its Bioavailability in High Geological Background Area

作　　者：刘永林 吴梅[1,2] 刘睿 李军[1,2] 刘属灵[1,2] 刘双燕[1,2] LIU Yonglin;WU Mei;LIU Rui;LI Jun;LIU Shuling;LIU Shuangyan(Key Laboratory of GIS Application Research,Chongqing Normal University,Chongqing 401331,China;School of Geography and Tourism,Chongqing Normal University,Chongqing 401331,China)

机构地区：[1]重庆师范大学GIS应用研究重点实验室,重庆401331 [2]重庆师范大学地理与旅游学院,重庆401331

出　　处：《土壤》2022年第4期834-840,共7页Soils

基　　金：重庆市教育委员会科学技术计划项目(KJZDK202100504,KJQN201900519);国家自然科学基金项目(41502329)资助。

摘　　要：选取秦岭地槽和川中前陆盆地结合部的重庆市城口县为研究区,采集表土样品115件,测定土壤pH、有机质(SOM)、主量元素、全硒(Se_(total))和磷酸盐提取态硒(Se_(bioa))含量。结果显示:研究区表土Se_(total)含量在0.013~14.5 mg/kg,中值为0.510 mg/kg,86.1%的土壤样品硒含量高于0.175 mg/kg,表明研究区表土整体处于富硒水平;表土Se_(bioa)含量中值为0.046 mg/kg。整体上,乌坪断裂以北地区表土Se_(total)和Se_(bioa)含量较高。随着地层从新到老其上发育的土壤Se_(total)和Se_(bioa)含量增高,表明研究区成土母岩控制着表土中硒及其生物有效性。综上,即使在高硒地质背景区,土壤硒及其生物有效性含量的分布也具有显著性差异,而这种差异主要由成土母岩控制,但也受到其他成土因素制约。Chengkou County,located in the junction of Qinling geosyncline and Yangtze Plate,is chosen as a study area,115 topsoil samples were collected,and soil pH,organic matter(SOM),major elements,total selenium(Se)in soil(Se_(total))and phosphate extracted Se(Se_(bioa))were determined.Results show that the concentration of Se_(total) is from 0.013 to 14.5 mg/kg with a median of 0.510 mg/kg,and the concentration of Se_(total) in 86.1%of samples is higher than 0.175 mg/kg,indicating a Se-enriched level.However,the median concentration of Se_(bioa) is 0.046 mg/kg.Generally,the concentrations of Se_(total) and Se_(bioa) are the highest in the north region of Wuping Fault,and the concentrations of Se_(total) and Se_(bioa) are increased with the increase of the stratum age,indicating that the pedogenic rock controls the spatial distributions of Se_(total) and Se_(bioa).This study proves the concentrations of Se_(total) and Se_(bioa) in topsoil varies greatly,even in the high geological background area,and the spatial difference is not only controlled by the pedogenic rock,but is also affected by other soil-forming factors.

关 键 词：地质高背景区 硒 生物有效性 土壤 乌坪断裂 

分 类 号：P445.4[天文地球—大气科学及气象学]