连续流动分析仪测定碳酸氢钠提取土壤有效磷的方法优化与研究  

Optimization on the method of sodium bicarbonate extraction of soil available phosphorus determined by continuous flow analyzer

作　　者：唐思宇 张丽萍[1] 王久荣[1] 袁红朝[1] 贺珍 耿梅梅[1] 陈闻 TANG Si-yu;ZHANG Li-ping;WANG Jiu-rong;YUAN Hong-chao;HE Zhen;GENG Mei-mei;CHEN Wen(Key Laboratory of Subtropical Agriculture,Institute of Subtropical Agriculture,Chinese Academy of Sciences,Changsha Hunan 410125)

机构地区：[1]中国科学院亚热带农业生态研究所重点实验室,湖南长沙410125

出　　处：《中国土壤与肥料》2024年第5期232-239,共8页Soil and Fertilizer Sciences in China

基　　金：中国科学院仪器功能开发项目(项目名称:恒温土壤微生物生物量培养-熏蒸装置的研制)。

摘　　要：为了提高土壤有效磷的检测灵敏度和检测效率,对《土壤有效磷的测定碳酸氢钠浸提-钼锑抗分光光度法》(HJ 704-2014)及《森林土壤的测定》(LY/T 1232-2015)中碳酸氢钠提取有效磷的检测方法进行了优化。设计了连续流动分析仪试剂配制方案及试剂流路,探讨了浸提方式、振荡速度、浸提温度、浸提时间及检测波长等实验条件对测定结果的影响,考察了方法的线性范围、检出限、精密度及准确度等参数,并比较了分光光度法与连续流动分析仪法检测结果。结果表明,在880 nm波长下,优化后的连续流动分析仪法检测碳酸氢钠浸提的有效磷的线性范围为0~3.00 mg/L,相关系数R2>0.999,检出限为0.004 mg/L,变异系数<5.0%,测定参比物质NSA 2[有效磷认定值(36±6)mg/kg]、NSA 4[有效磷认定值(14.5±2.6)mg/kg]、标准物质ASA-3a[有效磷认定值(29±3)mg/kg]分别为35.9、12.5和28.1 mg/kg,均在认定值范围内,可以准确测量有效磷低的土壤。优化后的连续流动分析仪法检测碳酸氢钠浸提土壤中有效磷含量具有自动进样、在线除气泡、在线恒温显色检测、试剂用量少及环境友好等优点,且实验周期短,测得数据的灵敏度、精密度和准确度良好,优势突出,可为第三次全国土壤普查高效准确测量碳酸氢钠浸提有效磷含量提供技术依据。In order to improve the detection sensitivity and efficiency of soil available phosphorus,the detection methods for extraction of available phosphorus by sodium bicarbonate in HJ 704-2014 Determination of soil available Phosphorus by sodium bicarbonate leaching-molybdenum antimony resistance spectrophotometry and LY/T 1232-2015 Determination of Forest soil were optimized.By designing the reagent preparation scheme and reagent flow path of continuous flow analyzer,the extraction method,oscillation velocity,temperature,time and detection wavelength on the test results were studied,the linear range,detection limit,precision and accuracy of the method were investigated,and the detection results of spectrophotometer method and continuous flow analyzer method were compared.The results showed that at 880 nm wavelength,the linear range of effective phosphorus extracted by sodium bicarbonate leaching was 0-3.00 mg/L,the correlation coefficient R2>0.999,the detection limit was 0.004 mg/L,and the coefficient of variation was<5.0%.The reference substance NSA 2[validated effective P(36±6)mg/kg],NSA 4[validated effective P(14.5±2.6)mg/kg]and standard substance ASA-3a[validated effective P(29±3)mg/kg]were measured as 35.9,12.5 and 28.1 mg/kg.The optimized continuous flow analyzer method for the detection of available phosphorus content in sodium bicarbonate leaching soil had the advantages of automatic sampling,online bubble removal,online constant temperature color detection,less reagent consumption and environmental friendliness.Besides,the experiment period was short,and the measured data were of good sensitivity,precision and accuracy,showing outstanding advantages.It could provide technical basis for the effective phosphorus content of sodium bicarbonate leaching in the third national soil survey.

关 键 词：土壤 碳酸氢钠浸提 有效磷 分光光度法 连续流动分析仪 

分 类 号：S153.6[农业科学—土壤学] O657.3[农业科学—农业基础科学]