青海东部富硒土壤中硒的形态和价态转化特征  

Speciation and valence state transformation characteristics of selenium-rich soil in eastern Qinghai

作　　者：宋晓珂[1] 李宗仁[1] 王金贵[1,2] SONG Xiaoke;LI Zongren;WANG Jingui(College of Agriculture and Animal Husbandry, Qinghai University, Xining 810016, China;State Key Laboratory of Plateau Ecology and Agri- culture, Qinghai University, Xining 810016, China)

机构地区：[1]青海大学农牧学院农林系,西宁810016 [2]省部共建三江源生态与高原农牧业国家重点实验室,西宁810016

出　　处：《干旱区资源与环境》2018年第6期136-142,共7页Journal of Arid Land Resources and Environment

基　　金：国家自然科学基金青年科学基金项目(41401354);青海省自然科学基金项目(2014-ZJ-928Q)"资助

摘　　要：文中主要探寻人为去除富硒土壤中可溶态硒(SOL-Se)和可交换态及碳酸盐结合态硒(EX-Se)后,土壤中的硒在不同培养温度和时间条件下的形态和价态转化特征。结果表明:土壤中硒的主要赋存形态为有机态硒(OM-Se),其次为EX-Se和铁锰氧化物结合态硒(FMO-Se),SOL-Se和残渣态硒(RES-Se)最少。SOL-Se和EX-Se中均存在Se^(4+)和Se^(6+),不存在Se^(2-),且主要以Se^(6+)为主,Se^(6+)占SOL-Se和EX-Se总量的73.9%~76.1%。土壤中SOL-Se和EX-Se含量均随着培养时间和培养温度的增加而增加,而FMO-Se、OM-Se和RES-Se含量随着培养时间的增加而减少。培养后土壤中SOL-Se和EX-Se的Se^(4+)和Se^(6+)含量均随着培养时间和温度的增加而增加。Use of selenium rich soil in the eastern Qinghai province as test soils,the speciation and valence state transformation characteristics of selenium in selenium rich soils were studied under different temperature and time after removal of soluble selenium and exchangeable and carbonate-bound selenium.The results showed that：the main forms of selenium in soil were organic matter-bound selenium,followed by exchangeable and carbonate-bound selenium and iron-manganese oxide-bound selenium,the soluble selenium and residual selenium were the least.Both of Se-（4＋） and Se-（6＋） were found in the soluble selenium and exchangeable and carbonate-bound selenium,there was mainly based on Se-（6＋） and no Se-（2-）,the Se-（6＋） accounts for 73.9% - 76.1% of the total amount of soluble selenium and exchangeable and carbonate-bound selenium.The contents of soluble selenium and exchangeable and carbonate-bound selenium in soil increased with the culture time and temperature increased,but the contents of iron-manganese oxide-bound selenium,organic matter-bound selenium and residual selenium decreased with the increase of incubation time.The effect of temperature on the transformation for the iron-manganese oxide-bound selenium,organic matter-bound selenium and residual selenium was not obvious.In the culture process,the re-formed soluble selenium and exchangeable and carbonate-bound selenium released from the mineralization decomposition of organic matter-bound selenium.The contents of Se-（4＋） and Se-（6＋） in soluble selenium and exchangeable and carbonate-bound selenium increased with the increase of incubation time and temperature.

关 键 词：富硒土壤 硒 形态 价态 转化特征 

分 类 号：X830.2[环境科学与工程—环境工程]