土壤-植物体系中硒生物有效性评价研究进展  

Advances in the evaluation of selenium bioavailability in soil-plant system

作　　者：周菲 彭琴 王敏[1] 薛明月 翟辉[1] 刘娜娜[1] 王梦柯 齐明星 梁东丽[1,3] Fei Zhou;Qin Peng;Min Wang;Mingyue Xue;Hui Zhai;Nana Liu;Mengke Wang;Mingxing Qi;Dongli Liang(College of Natural Resources and Environment,Northwest A&F University,Yangling 712100,China;Chongqing Key Laboratory of Environmental Materials&Remediation Technologies,Chongqing University of Arts and Sciences,Chongqing 402160,China;Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China,Ministry of Agriculture and Rural Affairs,Yangling 712100,China)

机构地区：[1]西北农林科技大学资源环境学院,杨凌712100 [2]重庆文理学院重庆环境材料与修复技术重点实验室,重庆402160 [3]农业农村部西北农业环境与植物营养重点实验室,杨凌712100

出　　处：《科学通报》2022年第6期461-472,共12页Chinese Science Bulletin

基　　金：国家自然科学基金(41571454,41171379)资助。

摘　　要：硒是哺乳动物必需的微量营养元素.鉴于其缺乏和毒害剂量间范围狭窄,在作物硒生物强化及硒污染土壤修复过程中需对土壤硒的生物有效性进行准确评价.但由于土壤是一个多相非均质的复杂体系,土壤类型较多且土壤性质差异很大,迄今国内外尚没有一个普遍适用的土壤有效硒测定及其有效性的评价方法.因此,本文综述了国内外常用的测定土壤有效硒含量的化学浸提法(包括单一浸提及连续浸提法)和新兴的梯度薄膜扩散技术(DGT法)的优缺点及适用性,提出0.1 mol/L KH2PO4-K2HPO4浸提法作为土壤有效硒测定方法;讨论了运用化学浸提法测定结果、基于此计算获得的特征参数(土壤结合强度(IR值)和移动系数(MF值))、植物硒含量表征土壤硒生物有效性的可行性,旨在为土壤-植物体系中硒生物有效性的评价提供依据.Selenium(Se)is an essential micronutrient for mammals,but its safe intake level is within a relatively narrow range.Dietary Se is the fundamental Se source for humans and primarily originates from soil.While,the content of bioavailable Se in soil is the key factor affecting the determination of its mobility and toxicity.Therefore,the bioavailability of Se in soil needs to be accurately determined and evaluated for the biofortification of Se and its pollution remediation.Due to the considerable differences in soil properties among different soil types and the soil-system complexity,no universal applicable method can be used to measure and evaluate Se bioavailability in soil.Chemical extraction methods(including single extraction and sequential extraction methods)and diffusive gradients in thin-film technique(DGT method)are commonly used to determine bioavailable Se in soil.Chemical extraction method is easy to operate and low cost,but its extractant lacks universal applicability,resulting in incomparable results among different chemical extraction methods.Selenium could also be re-adsorbed and redistributed during chemical extraction,which may lead to certain errors for the extraction results.DGT can simulate the dynamic absorption process of elements by plant roots,but its adsorption film is ion selective and costly,which affects its practical application.Obviously,different bioavailable Se-determination methods have various application scopes and significance,and each has its advantages and disadvantages.After comprehensively comparing different methods,the single-extraction method with 0.1 mol/L KH2PO4-K2HPO4 solution is recommended as the optimum method to determine bioavailable Se in soil.Furthermore,chemical-extraction result,parameter-evaluation method(relative binding intensity and mobility factor value)and plant-indicator method are confirmed to quantitatively characterize Se bioavailability in soil-plant system to a certain extent.However,similar to the determination methods of bioavailable Se in soil,ea

关 键 词：土壤 硒生物有效性 化学浸提 梯度扩散薄膜技术(DGT法) 评价指标 

分 类 号：S154.4[农业科学—土壤学]