流动注射分析法与紫外分光光度法测定土壤硝态氮含量的比较

Comparison of FIA and UV Methods in Determining Soil Nitrate Nitrogen

以河北省主要土壤类型褐土、潮土和潮褐土区域的10个代表性耕层土壤样品为试验材料,分别利用流动注射分析法和紫外分光光度法对同一土壤浸提液进行硝态氮含量测定,并将测定结果进行比较,分析了2种测定方法的精密度和准确度。结果表明：流动注射分析法的加标回收率为95.00%-105.00%,相对标准差为0.99%-7.02%、平均值为4.43%;紫外分光光度法的加标回收率为96.00%-104.50%,相对标准差为3.27%-8.90%、平均值为5.82%。2种测定方法准确度均较高,但流动注射分析法的精密度高于紫外分光光度法,土壤硝态氮含量测定结果基本一致。

Ten soil samples collected from primary soil types regions in Hebei Province were used to study the precision and accuracy of determining soil nitrate nitrogen by flow injection analysis method and ultraviolet spectrophotometer method, and compared the data between two analysis methods. The results showed that the recovery rate of nitrogen and relative standard variance of the flow injection analysis method were 95.00%-105.00%, and 0.99%-7.02% with a mean of 4.43%, respectively, and 96.00%-104.50%, 3.27%-8.90% with a mean of 5.82% for ultraviolet spectrophotometer method. There were the similar higher accuracy of determining soil nitrate nitrogen by two methods,but the precision of flow in jection analysis method were higher than that of ultraviolet spectrophotometer method. There were the identical results of determining soil nitrate nitrogen between two methods.