Aluminum chemistry of nonallophanic Andosols

非钠基安多土的铝化学

• 批准号: 08660081
• 负责人: TAKAHASHI Tadashi
• 金额: $ 1.47万
• 依托单位: Akita Prefectural College of Agriculture
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1996
• 资助国家: 日本
• 起止时间: 1996 至 1998
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-08660081/
• 关键词: volcanic ash soils; active Al; aluminum solubility; nonallophanic Andosols; Al-humus complexes; exchangeable Al; Andisols

The aim of this study is to expand upon previous investigations about aluminum chemistry by examining aluminum solubility and release rates in soils dominated by Alhumus complexes. Aluminum solubility relationships over the pH range 3-5 were determined in a 30-d equilibration study. Aluminum release rates were measured using a stirred, flow-through reaction vessel with 10^<-3> M acetate buffer adjusted to pH 3.5, 4.0 and 4.5 for pretreated soil samples with Na-pyrophosphate, acid oxalate and KCl solutions.The nonallophanic Andosol samples displayed pAl versus pH slopes of 2.0-2.4 and solubilities considerably lower than those of common Al(OH)_3 phases. The soil samples showed very rapid Al release rates. The Al release rates were greatly dependent on the pH and ion strength of extracting solution. Pyrophosphate treatment reduced Al release rates to very low levels indicating that Al-humus complexes were the primary source of dissolved Al.Some non-allophanic soils showed that the aluminum release rates and the total amount of Al released from KCl-treated residues were greater than or nearly identical with those of non-treated soil samples. Thus, the amount of 1M KCl-extractable Al does not always reflect the amount of exchangeable Al in soils dominated by Al-humus complexes.This study and the literature showed that the amount of KCl-extractable Al is closely related to the amount of organically complexed Al. These data indicates that the dynamics of aluminum in nonallophanic Andosols is largely influenced by the exchange of Al ions with humic substances.

本研究的目的是通过检查铝在以铝腐殖质复合物为主的土壤中的溶解度和释放率，扩展之前对铝化学的研究。在 30 天的平衡研究中确定了 pH 范围 3-5 内铝的溶解度关系。使用搅拌的流通式反应容器测量用焦磷酸钠、酸式草酸盐和KCl溶液预处理的土壤样品的10^-3M乙酸盐缓冲液的pH值调节至3.5、4.0和4.5。非水铝酸Andosol样品显示pAl对pH值斜率为2.0-2.4并且溶解度显着低于普通Al(OH)_3的溶解度。 阶段。土壤样品显示出非常快的铝释放速率。 Al 的释放速率很大程度上取决于提取液的 pH 值和离子强度。焦磷酸盐处理将铝释放率降低到非常低的水平，表明铝腐殖质复合物是溶解铝的主要来源。一些非水铝英土壤表明，经KCl处理的残留物的铝释放率和铝释放总量大于或几乎相同于未处理的土壤样品。因此，1M KCl可萃取Al的量并不总是反映以Al-腐殖质复合物为主的土壤中可交换Al的量。本研究和文献表明，KCl可萃取Al的量与有机络合Al的量密切相关。这些数据表明，非水铝酸安多土中铝的动力学很大程度上受到铝离子与腐殖质交换的影响。

项目成果

高橋正・R.Dahlgren,: "Possible control of aluminum solubility by 1M KCl treatment in some soils dominated by aluminum-humus complexes" Soil Science and Plant Nutrition. 44. 43-51 (1998)

Tadashi Takahashi 和 R. Dahlgren，：“在一些以铝-腐殖质复合物为主的土壤中，通过 1M KCl 处理可能控制铝的溶解度”，《土壤科学与植物营养》，44. 43-51 (1998)。