测定土壤硝态氮的紫外分光光度法与其他方法的比较  

COMPARISON BETWEEN ULTRAVIOLET SPECTROPHOTOMETRY AND OTHER METHODS IN DETERMINATION OF SOIL NITRATE-N

作　　者：宋歌[1] 孙波[1] 教剑英[1] 

机构地区：[1]中国科学院南京土壤研究所

出　　处：《土壤学报》2007年第2期288-293,共6页Acta Pedologica Sinica

基　　金：中国科学院知识创新项目(KSCX2-YW-N-038);中国科学院野外台站研究基金项目"农田系统有机源氮素的区域迁移过程"资助

摘　　要：使用酚二磺酸法、还原蒸馏法、镀铜镉还原-重氮化偶合比色法和改进紫外分光光度法(校正因数法)测定了中国9种不同类型土壤的硝态氮含量,分析了改进紫外分光光度法与其余三种测定方法的差异及其适用性。统计分析表明对于有机质含量低于50 g kg-1的矿质土壤,可以使用2.2作为校正因数,四种分析方法的测定值具有极显著的相关性,尤其是紫外分光光度法与酚二磺酸法的测定结果最为接近,没有极显著差异;对于有机质含量接近和高于50 g kg-1的土壤,校正因数还需要修改。紫外分光光度法具有操作简单、测定速度快等优点,适用于批量快速测定。A modified UV spectrophotometry is compared with the phenoldisulfonic acid colorimetry, MgO distillation and FeSOa-Zn reduction method, and eopperized cadmium reduction method in determining NO3- concentration in soil extracts of nine different types of soils. In the UV speetrophotometry, the value of correction factors （f） is determined by measuring the absorbanee of the soil extract solution in the absence of NO3- . The mean value of f is 2.2. Statistically, it is highly correlated between the four methods in determination value, particularly in mineral soils with low organic matter （less than 50 g kg^-1）. All results show no significant difference between UV speetrophotometry and phenoldisulfonie acid eolorimetry. However, the f value still needs to be readjusted in soils with high organic matter （ more than 50 g kg^- 1 ）. In general, UV spectrophotometry is simple and rapid, and it can be applied to rapid analysis of large batches of soil samples.

关 键 词：土壤硝态氮 紫外分光光度法 校正因数 酚二磺酸法 还原蒸馏法 镀铜镉还原-重氮化偶合 比色法 

分 类 号：S151.95[农业科学—土壤学]