土壤中交换性铝含量的测定方法改进  

An Improved Method for Determination of Exchangeable Aluminum in Soil

作　　者：崔朋辉 许小丽[2] 林思祖[3] 张金彪[1] 

机构地区：[1]福建农林大学生命科学学院,福建福州350002 [2]福建农林大学资源与环境学院,福建福州350002 [3]福建农林大学林学院,福建福州350002

出　　处：《福建农业学报》2016年第3期280-284,共5页Fujian Journal of Agricultural Sciences

基　　金：国家自然科学基金(31370609)

摘　　要：根据铝试剂与铝反应形成红色络合物的原理,在测定波长、反应温度、显色时间、缓冲溶液酸度、显色剂用量和掩蔽剂用量等测定条件优化的基础上,分别采用改进的分光光度法和全自动间断化学分析法测定了土壤中的交换性铝含量,并与国家标准方法比较。结果表明,优化后的分光光度法中的铝浓度在0~0.5mg·L^(-1)范围内与吸光度呈良好的线性关系,相关系数为0.999 4;全自动间断化学分析法中的铝浓度在0~2.5mg·L^(-1)范围内与吸光度的线性关系良好,相关系数为0.999 6。两方法用于土壤样品中交换性铝测定的回收率分别为95.90%~101.16%和99.83%~104.34%,相对标准偏差平均值分别为1.913%和1.861%。所建立的两种方法均具有快速、准确的特点。其中,全自动间断化学分析法在自动化程度、分析速度和试剂消耗量等方面更优,是一种新的测定土壤中交换性铝的理想方法。Content of exchangeable aluminum （Al） in soil was determined by using a modified spectrophotometry and the auto discrete analysis. The results were compared with that obtained by using the national standard testing method. Theoretically, the modified methods were based on the reaction between A1 and aluminon that generated a stable, red-colored complex. The testing conditions, including wavelength, reaction temperature, reaction time, pH of buffer solution, content of aluminon, and content of masking agent, were optimized. The resulting spectrophotometry had a linear range between 0 and Al 0. 5 mg · L^-1 with a correlation coefficient of 0. 999 4. The linear range on the method using an auto discrete analyzer was 0 to Al 2.5 mg·L^-1 with a correlation coefficient of 0. 999 6. On the soil samples, the recovery rates of the two methods were 95. 90%- 101.16% and 99.83%- 104. 34%, respectively; and, the average RSDs were 1. 913% and 1. 861%, respectively. Both testing methodologies were faster and more accurate than the standard method. However, the auto discrete analysis was superior in regard to automation, efficiency, and reagent consumption, it was considered a choice for the application.

关 键 词：土壤 交换性铝 全自动间断化学分析 

分 类 号：S151.95[农业科学—土壤学]