淹水条件对土壤砷形态转化的影响-应用生态学报.PDF

应 用 生 态 学 报摇 2010年11月摇 第21卷摇 第11期摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 摇 ChineseJournal of Applied Ecology,Nov. 2010,21(11):2997-3000 淹水条件对土壤砷形态转化的影响* ** 曾希柏 摇 和秋红摇 李莲芳摇 白玲玉 (中国农业科学院农业环境与可持续发展研究所/ 农业部农业环境与气候变化重点开放实验室,北京 100081) 摘摇 要摇 通过淹水条件下的培养试验,探讨了外源二甲基砷酸(DMA)、一甲基砷酸(MMA)、 砷酸盐[As(V)]在土壤中的动态转化规律. 结果表明:随着培养时间的推移,加入土壤中的 DMA和MMA均主要转化为As(V),且土壤中As(V)含量均呈增加趋势,培养到150 d 时土 壤中As(V)含量均显著高于1d 时的含量(P0郾01). 外源DMA通过脱甲基化作用,在30 d 内即基本转化为As(V),且有少量的亚砷酸盐[As(芋)]生成;而外源MMA 的转化速度相对 较慢,培养60 d后才基本完成向As(V)的转化,同时伴随少量DMA和As(芋)的生成;在淹 水条件下外源As(V)含量随培养时间的增加而逐渐降低,该过程中除有少量As(芋)生成外, 其形态基本未发生改变. 关键词摇 土壤摇 淹水摇 砷摇 形态转化 文章编号摇 1001-9332(2010)11-2997-04摇 中图分类号摇 X53摇 文献标识码摇 A Influence of flooding on form transformation of soil arsenic. ZENG Xi鄄bai,HE Qiu鄄hong,LI Lian鄄fang,BAI Ling鄄yu (Ministry of Agriculture Key Laboratory of Agro鄄Environment Climate Change,Instituteof AgriculturalEnvironmentandSustainableDevelopment,ChineseAcademy of Ag鄄 ricultural Sciences,Beijing 100081,China).鄄Chin.J.Appl.Ecol. ,2010,21(11):2997-3000. Abstract:An incubationtestwasconductedto study the dynamicsof exogenously supplied dimeth鄄 ylarsenic acid (DMA),monomethylarsonicacid (MMA),andAs(V)insoilunderflooding. With the increasing time of incubation,the exogenously supplied DMA and MMA were mainly trans鄄 formed into As(V), and the As(V) concentration increased, being significantly higher after incubated for 150 days,compared with that after incubated for 1 day. The exogenously supplied DMA was demethylated into As(V) within 30 days,accompanied by a little As(III),while the transformationrateof exogenously supplied MMAwasrather slowwithin60 days,accompaniedby a little As(芋) and DMA. The exogeno