土壤中铝的溶出及形态研究

Studies on the Leaching and Species of Aluminum in Soil

用连续提取法研究１ｍｏｌ／ＬＫＣｌ，１ｍｏｌ／ＬＮＨ４Ａｃ，１ｍｏｌ／ＬＨＣｌ和０．５ｍｏｌ／ＬＮａＯＨ４种化学浸提液对土壤中铝的溶出。溶出铝用羊毛铬花菁Ｒ比色法测定。结果表明，铝的溶出量与土壤类型、总铝、有机质含量等因素有关。１ｍｏｌ／ＬＫＣｌ浸提液对酸性土能溶出一定量的交换态铝，而对非酸性土则不能溶出或铝溶出量极微．０．５ｍｏｌ／ＬＮａＯＨ浸提出的铝量与总铝量之间有显著相关性．

The leaching and chemical forms of aluminum in soil by sequential fraction procedure were studied.Solutions used sequentially to extract Al are inorder of 1 mol/L KCl,1 mol/L NH4Ac,1 mol/L HCl and 0.5 mol/L NaOH.The spectrophotometric determination of leaching Al was performed with Eriochrom Cyamine RC.It has been found that the type of soil and the amounts of organic materials and total Al in soil have a siginificant effect on the amount of leaching Al.A certain amount of exchangeable Al can be leached from acid soil with 1 mol/L KCl extractant,however,it can not be leached from alkaline soil.The leaching Al extracted with 0.5 mol/L NaOH is correlated at a high level of significance with the total Al in soil.