一种土壤中缓效钾测定的改进方法

An improved method for determination of non-exchangeable potassium content in soil

土壤缓效钾是土壤有效钾的一部分,通过对NY/T 889-2004《土壤速效钾和缓效钾含量的测定》测定缓效钾含量的前处理方法进行改进,用标准COD消解器消解替代了油浴(或磷酸浴),改进后的方法在精密度方面平行测定最大相对相差均≤8%,在准确度方面标准物质测定的单次结果均在标准值范围之内。实际样品测定方面,改进前和改进后的方法相对相差均≤8%。改进后的方法有较好的精密度和正确度,操作更加安全,消解效率高。

Non-exchangeable potassium content in soil is a part of soil available potassium.The pre-treatment method for determining the content of non-exchangeable potassium in NY/T 889-2004“Determination of exchangeable potassium and non-exchangeable potassium content in soil”was improved.The standard COD digester was used to digest instead of oil bath(or phosphoric acid bath).The maximum relative difference of parallel determination in the precision of the improved method was≤8%.In terms of accuracy,all the single determination results of reference materials were within the range of standard values.In terms of actual sample determination,the relative difference between the un-improved method and the improved method was≤8%.The improved method has better precision and accuracy,and the operation is more safe and has higher digestion efficiency.