紫外分光光度法测定土壤硝态氮校正因数的优化  

Optimization of Correction Factor of Soil Nitrate Nitrogen by Ultraviolet Spectrophotometry

作　　者：苗杰 李斐 张加康 魏邦泰 贾禹泽 杨海波 MIAO Jie;LI Fei;ZHANG Jiakang;WEI Bangtai;JIA Yuze;YANG Haibo(College of Grassland, Resources and Environment, Inner Mongolia Agricultural University, Hohhot 010011, China;Inner Mongolia Key Laboratory of Soil Quality and Nutrient Resources, Hohhot 010011, China)

机构地区：[1]内蒙古农业大学草原与资源环境学院,内蒙古呼和浩特010011 [2]内蒙古自治区土壤质量与养分资源重点实验室,内蒙古呼和浩特010011

出　　处：《华北农学报》2019年第S01期204-212,共9页Acta Agriculturae Boreali-Sinica

基　　金：公益性行业(农业)科研专项项目(201503106)

摘　　要：土壤硝态氮在旱地作物氮素养分管理中具有极其重要的作用,紫外分光光度法测定土壤硝态氮具有操作简便、测定速度快以及干扰因素较少等优点被多数实验室所青睐,然而紫外分光光度法中校正因数由于受到浸提剂、波长选择以及土壤类型影响具有不确定性需要优化。选取内蒙古从东到西不同生态区域的8种土壤类型进行了土壤硝态氮的测定,研究了浸提剂种类以及波长选取和土壤类型对紫外分光光度法中校正因数的影响。结果表明,浸提剂和波长对于校正因数都具有重要的影响,CaCl2和KCl浸提剂得出的校正因数值之间没有相关性,210,220 nm处的校正因数值有极显著的相关性,且210 nm处的校正因数值普遍高于220 nm。不同土壤类型在不同浸提剂和波长对校正因数的影响不尽相同。KCl浸提剂在210,220 nm处的校正因数值分别为3.4,2.8,而CaCl2浸提剂在210,220 nm处的校正因数值分别为4.4,2.9。在不同浸提剂和不同波长条件下测定硝态氮含量与酚二磺酸法相比,以KCl为浸提剂选取220 nm波长(校正因数2.8)有最低的RMSE和RE%,分别为1.8,15.6%,流动分析法和反射仪法的比较进一步证明了KCl浸提剂220 nm处修正校正因数为2.8的可靠性。Soil nitrate nitrogen plays an important role in nitrogen nutrient management in dryland crops.Ultraviolet spectrophotometry for the determination of soil nitrate nitrogen has the advantages of simple operation,fast measurement and less interference factors,but it is favored by most laboratories.The correction factor in the spectrophotometry requires optimization due to the uncertainty of the extractant,wavelength selection,and soil type.Soil nitrate nitrogen was determined from eight soil types in different ecological regions from east to west in Inner Mongolia.The effects of extractant species,wavelength selection and soil type on the correction factor in UV spectrophotometry were studied.The results showed that the extractant and the wavelength had an important influence on the correction factor.There was no correlation between the correction factor values obtained by CaCl2 and KCl extractant,and there was a significant correlation between the correction factor values at 210,220 nm.And the correction factor value at 210 nm was generally higher than 220 nm.Different soil types had different effects on correction factors for different extractants and wavelengths.The correction factors for KCl extracts at 210,220 nm were 3.4 and 2.8,respectively,while the CaCl2 extracts had correction values of 4.4 and 2.9 at 210,220 nm,respectively.Compared with the phenol disulfonic acid method under different extracting agents and different wavelengths,the lowest RMSE and RE%were obtained by using KCl as the extractant at 220 nm wavelength(correction factor 2.8),Which was 1.8 and 15.6%respectively.The comparison between flow analysis and reflectometry further demonstrated that a KCl extractant with a correction correction factor of 2.8 at 220 nm was feasible.

关 键 词：土壤硝态氮 酚二磺酸法 紫外分光光度法 校正因数 

分 类 号：S151.95[农业科学—土壤学]