硒-砷交互作用对白菜砷和硒吸收转运的影响  

Interactions between arsenic and selenium uptake and translocation in Chinese cabbage

作　　者：秦玉燕[1] 王运儒[1] 时鹏涛[1] 蓝唯[1] 李鸿[1] 吴凤 张莉娟 QIN Yuyan;WANG Yunru;SHI Pengtao;LAN Wei;LI Hong;WU Feng;ZHANG Lijuan(Laboratory of Quality and Safety Risk Assessment for Agricultural Product(Nanning),Ministry of Agriculture,Guangxi Subtropical Crops Research Institute,Nanning,530001,China)

机构地区：[1]广西壮族自治区亚热带作物研究所农业农村部农产品质量安全风险评估实验室(南宁),南宁530001

出　　处：《环境化学》2021年第9期2640-2648,共9页Environmental Chemistry

基　　金：广西青年科学基金(2018GXNSFBA281171)资助。

摘　　要：本文为研究硒和砷的交互作用对白菜砷和硒吸收转运的影响,采用土壤盆栽试验,研究无添加砷、轻度砷污染(100 mg·kg^(-1))和中度砷污染(200 mg·kg^(-1))条件下,施硒(0、2.5、5.0、7.5 mg·kg^(-1))对白菜不同部位砷、硒含量及地上部位砷、硒形态组成的影响.结果表明,无添加砷条件下,2.5 mg·kg^(-1)和7.5 mg·kg^(-1)硒处理显著降低地下部位砷含量;轻度砷污染条件下,7.5 mg·kg^(-1)硒处理显著降低地下部位砷含量,5.0 mg·kg^(-1)和7.5 mg·kg^(-1)硒处理促进砷向地上部位转运,显著提高地上部位砷含量;中度砷污染条件下,5.0 mg·kg^(-1)和7.5 mg·kg^(-1)硒处理抑制砷向地上部位转运,显著提高地下部位砷含量.硒处理浓度为2.5 mg·kg^(-1)时,100 mg·kg^(-1)和200 mg·kg^(-1)砷处理抑制硒向地上部位转运,显著降低地上部位硒含量;硒处理浓度为5.0 mg·kg^(-1)时,100 mg·kg^(-1)砷处理促进硒向地上部位转运,显著降低地下部位硒含量;硒处理浓度为7.5 mg·kg^(-1)时,200 mg·kg^(-1)砷处理促进根系对硒的吸收,地上、地下部位硒含量显著提高.外源砷的添加促进As(Ⅴ)还原为As(Ⅲ);外源硒对白菜地上部分砷形态组成没有显著影响.外源硒的添加促进了Se(Ⅳ)向Se(Ⅵ)及有机硒转化.外源砷或硒处理均能提高根际土壤p H.中度砷污染条件下,7.5 mg·kg^(-1)硒处理显著降低根际土壤有效态砷含量.硒对白菜吸收转运砷的影响在不同砷污染条件下存在差异,轻度砷污染条件下,较高浓度硒处理提高白菜可食用部位砷污染风险,建议土壤施硒以低浓度为宜(<2.5 mg·kg^(-1)).Interactive effects between arsenic(As)and selenium(Se)on uptake and translocation of As and Se in Chinese cabbage(Brassica pekinensis L.)were investigated in pot experiment.Three levels of As additions(0,100 mg·kg^(-1) and 200 mg·kg^(-1))and 4 Se levels(0,2.5,5.0 mg·kg^(-1) and7.5 mg·kg^(-1))for each As addition were designed,and As contents,Se contents,As speciation and Se speciation in Chinese cabbage were determined.The results showed that 2.5 mg·kg^(-1) and 7.5 mg·kg^(-1) Se treatments significantly reduced As content in underground part under the condition of without As addition.Under mild As pollution condition(100 mg·kg^(-1)),7.5 mg·kg^(-1) Se treatments decreased As content in underground part,and 5.0 mg·kg^(-1) and 7.5 mg·kg^(-1) Se treatments promoted the transport of As from root to aboveground,thus leading to the significantly increased of As in aboveground part.Under moderate As pollution condition(200 mg·kg^(-1)),5.0 mg·kg^(-1) and 7.5 mg·kg^(-1) Se treatments significantly increased As content in underground part and inhibited the transport of As from root to aboveground.100 mg·kg^(-1) and 200 mg·kg^(-1) As treatments inhibited the transport of Se from root to aboveground,and significantly reduced Se content in aboveground part at 2.5 mg·kg^(-1) Se level.While 100 mg·kg^(-1) As treatment promoted the transport of Se from root to aboveground,and significantly reduced Se content in the underground part at 5.0 mg·kg^(-1) Se level.When the application of Se at 7.5 mg·kg^(-1),200 mg·kg^(-1) As treatment significantly increased Se content in the aboveground and underground parts.The addition of exogenous As promoted the reduction of As(Ⅴ)to As(Ⅲ),and the exogenous Se had no significant effect on As speciation in the aboveground part.The addition of exogenous Se promoted the transformation of Se(Ⅳ)to Se(Ⅵ)and organic Se.Both exogenous As and Se addition could increase the p H of rhizosphere soil.Under moderate As pollution condition,7.5 mg·kg^(-1) Se treatment significantly r

关 键 词：硒 砷 白菜 转运 形态组成 

分 类 号：X503.231[环境科学与工程—环境工程]