岩矿测试2025，Vol.44Issue(6)：1192-1202,11.DOI:10.15898/j.ykcs.202504140087
碳酸氢钠浸提法测定有效磷的除浊及脱色新方法
A New Method for Turbidity Removal and Decolorization in the Determination of Available Phosphorus Using Sodium Bicarbonate Leaching
摘要
Abstract
The determination of available phosphorus in soil is crucial for evaluating soil fertility and guiding rational fertilization.However,traditional sodium bicarbonate extraction methods encounter significant challenges when dealing with soils rich in organic matter,as the filtrate often becomes relatively dark-colored or turbid,thereby affecting the detection results.The aim of this study was to develop a novel decolorization and turbidity-removal method for sodium bicarbonate extraction solutions,ensuring accurate determination of soil available phosphorus content in high-organic-matter soils.The new method integrated the ion-exchange enhancement of sodium chloride on soil colloids and the oxidative decolorization of sodium hypochlorite.The effects of sodium chloride concentration in the sodium bicarbonate solution,sodium hypochlorite dosage,decolorization time,and color-development stabilization time were systematically optimized.Results indicated that a 2%sodium chloride concentration in the sodium bicarbonate extraction solution rendered the filtrate clear.When 2 drops of 1∶1 sodium hypochlorite were added to the filtrate and the standing time was within 15min,the color of the filtrate was removed,which did not interfere with the color change of the pH adjustment indicator,and ensured accurate detection results.Within 0.75 to 6h of color development,the detection result remained stable.When this method was used to determine the content of available phosphorus in three soil available state component analysis reference materials and two quality control reference materials,the results were all within the standard value range,the relative standard deviation(RSD,n=4)was less than 3.40%,and the absolute error was less than 1.5mg/kg.In conclusion,the newly developed method effectively addressed the turbidity and color issues of sodium bicarbonate extracts,eliminating detection interferences.With high accuracy,reliability,and ease of operation,it provides a practical solution.The BRIEF REPORT is available for this paper at http://www.ykcs.ac.cn/en/article/doi/10.15898/j.ykcs.02504140087.关键词
碳酸氢钠浸提法/土壤有效磷/滤液浑浊/滤液颜色/次氯酸钠Key words
sodium bicarbonate extraction method/available phosphorus in soil/filtrate turbidity/filtrate color/sodium hypochlorite分类
农业科技引用本文复制引用
李朝英,郑路,郑之卓,刘士玲,李华..碳酸氢钠浸提法测定有效磷的除浊及脱色新方法[J].岩矿测试,2025,44(6):1192-1202,11.基金项目
崇左凭祥友谊关森林生态系统广西野外科学观测研究站创新能力建设项目(桂科AD25069098) （桂科AD25069098）
广西林业科技推广示范项目(桂林科研[2022]第27号,2023GXLK45) （桂林科研[2022]第27号,2023GXLK45）
