Surface-chemical study on effects of wet and dry conditions to soil colloids.

潮湿和干燥条件对土壤胶体影响的表面化学研究。

• 批准号: 09660069
• 负责人: KITAGAWA Yasuo
• 金额: $ 1.15万
• 依托单位: Fukui Prefectural University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 1997
• 资助国家: 日本
• 起止时间: 1997 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09660069/
• 关键词: Soil Colloids; Charge Characteristics of Soil Particles; Dispersibility of Soil Particles; Particle-size Distribution of Soils; Soil Clay Mineralogy; 粘土鉱物学; 界面化学; 土壌粘土鉱物; 荷電特性; 粒径分布; 土壌の乾湿

The abnormal hardening of topsoil after puddlig so called "itsuki" has been serious problem in some rotational paddy fields of middle- to coarse-textured soils. This study was carried out for the purpose of clarifying the itsuki phenomenon by application of surface chemistry. The results is summarized as follows :Total contents of iron oxides decreased, but amorphous iron oxides which affect closely to pH-dependent charge of soil colloides increased relatively, in the re-wetted soils after a strongly reductive procedure of the air-dried ones which were collected from continuous cropping paddy fields. Organic materials in these soils were also decreased by the reductive procedure, and it was suggested that this losted organic materials combined with reached iron oxides.Charge characteristics of soil colloids were estimated by applying several species of clay minerals. Montmorillonite had high negative charge constantly in the wide range of pH values, and negative charge of kaolin minera … More ls were pH-independent but it was low. On the other hand, positive and negative charge of allophane were both extremely pH-dependent, pont of zero net charge was observed at pH 5.5.A casium ion adsorption methods which had been presented in this study was very effective for the investigations on characteristics of cation exchange capacity and point of zero net charge in soil colloids. This new method was able to prevent contaminations during the measurement procedures compared with the previous methods by using sodium or potassium ions.Determination of particle-size distribution of soils by a laser scattering method was compared with the customary sedimentation method, the high correlation was established between them. This method was useful especially for the observation of continuous distribution of particle size in same clay or soil sample.An electrokinetic sonic amplitude method should be effective for the estimation of ζ potential of clay minerals and soil colloids because of probability to measure rapidly it in wide rage of pH value. Less

在一些中、粗粒化土壤的轮作稻田中，耕后耕层的异常硬化，即所谓的“一次硬化”，一直是一个严重的问题。本研究的目的是通过应用表面化学来澄清itsuki现象。结果表明：重茬稻田风干土壤经强还原处理后，再湿润土壤中总铁氧化物含量降低，而与土壤胶体pH依赖性电荷密切相关的无定形铁氧化物含量相对增加。土壤中的有机质也因还原过程而减少，并与铁氧化物结合。用几种粘土矿物测定了土壤胶体的电荷特性。蒙脱石在较宽的pH值范围内始终具有较高的负电荷，高岭土矿带负电荷， ...更多信息 LS不依赖于pH值，但较低。水铝英石的正负电荷均具有强烈的pH依赖性，在pH5.5时出现净零电荷蓬特。本研究提出的铯离子吸附法是研究土壤胶体阳离子交换容量和净零电荷点的有效方法。与以往的钠、钾离子测定方法相比，激光散射法能有效地避免测量过程中的污染，并与传统的沉降法进行了比较，两者具有良好的相关性。电动声幅法能在较宽的pH值范围内快速测定粘土矿物和土壤胶体的吸附电位，是估算粘土矿物和土壤胶体吸附电位的有效方法。少

项目成果

Itami, K.: "Charge characteristics if clays evaluated with caesium chloride"Special neference to dispersion behavior. Clay Science. 11(印刷中). (2000)

Itami, K.：“用氯化铯评估粘土的电荷特性”，特别提及粘土科学 11（出版中）。

Itami,K. and Tamamura,T.: "Evaluation of cation exchange capacity of montmoril Conite using"caesium chloride. Clay Science. 10-6. 469-476 (1999)

伊丹，K.

Kurihara H., Kitagawa, Y. and Itami, K.: "Determination of particle-size distribution by a laser scattering method."Pedologist. 42-2. 73-81 (1999)

Kurihara H.、Kitakawa, Y. 和 Itami, K.：“通过激光散射法测定粒度分布。”土壤学家。

Itami, K.: "Evaluation of cation exchange capacity of montmorillonite using Casium"Chloride. Clay Science. 10. 469-476 (1999)

Itami, K.：“使用氯化铯评估蒙脱土的阳离子交换能力。”

栗原宏彰(北川靖夫): "レーザー散乱法による土壌の粒経測定"ペドロジスト. 43. 73-81 (1999)

Hiroaki Kurihara（Yasuo Kitakawa）：“利用激光散射法测量土壤颗粒大小” 土壤学家 43. 73-81 (1999)。