不同制样粒径对土壤有效养分测定结果的影响

Effect of Soil Particle Size on the Determination of Available Nutrient in Soil

研究选择3种母质上发育的5种土壤,分别设置1mm和2mm制样粒径处理,采用常规分析方法对pH值、碱解氮、有效磷、速效钾和有效硅等属性进行了测定。结果表明:土壤制样粒径不同对分析结果的准确度和精密度均有一定程度影响,1mm粒径土壤的测定精密度略高于2mm粒径土壤,其中有效磷测定误差较大;1mm和2mm粒径土壤养分含量测定结果依养分种类不同而存在差异,对于碱解氮、速效钾和有效硅,1mm粒径土样测定结果略高,但是相差不大,而有效磷则相差较大,1mm粒径土样测定结果普遍低于2mm土样,平均低6.9%,最多低30%以上;pH测定不受粒径影响。

Five kinds of soil developed from 3 parent materials were selected and ground to pass lmm and 2mm sieve pore as two treatments of soil sample. The conventional methods were used to detect pH value, alkaline nitrogen, available phosphorous, available potassium and available silicon for the five soil samples. The results showed that soil particle size had certain influences on the accuracy and precisions of analysis results. The precisions of lmm grain size was higher than that of 2mm grain size and the error for measuring available phosphorous was the largest. There were differences among the concentration of soil nutrients between lmm and 2mm grain size according to different kinds of nutrients. For alkaline nitrogen, available potassium and available silicon, the determination concentration of lmm grain size was higher than that of 2mm grain size, but there was no marked difference. For available phosphorous, the determination concentration of lmm grain size was lower by 6.9% on average than that of 2mm grain size. The sampling particle size had no influence on pH value.