不同浸提剂以及保存方法对土壤矿质氮测定的影响  

Content of soil mineral nitrogen as influenced by sample extraction and preservation

作　　者：朱强[1] 马丽[1] 马强 李丽 陈宝成[1] 刘之广[1] 张民[1] 

机构地区：[1]土肥资源高效利用国家工程实验室国家缓控释肥工程技术研究中心山东农业大学资源与环境学院,泰安271018 [2]山东德州市农业科学研究院,德州253000 [3]山东德州市水利局,德州253000

出　　处：《中国生态农业学报》2012年第2期138-143,共6页Chinese Journal of Eco-Agriculture

基　　金："十二五"国家科技支撑计划项目(2011BAD11B01;2011BAD11B02);国家"948"项目(2011-G30);国家水体污染控制与治理科技重大专项(2008ZX07101-005);山东省农业科技成果转化资金(鲁科农字[2010]79号)项目资助

摘　　要：为探明影响土壤矿质氮测定的因素,从棕壤、潮土和黄棕壤3种类型土壤中各采集10个经不同施肥处理的土样,用连续流动注射分析仪测定经不同浸提剂以及不同保存方法处理后土样的NO3-N和NH4-N含量。结果表明:不论是棕壤、潮土还是黄棕壤,2 mol.L?1 KCl提取硝态氮的数量与0.01 mol.L?1 CaCl2提取的数量相关性均达到P<0.01水平;3种土壤各个土样硝态氮含量的测定值多表现为新鲜土<冷冻土<风干土;将鲜样浸提后作短时间的冷冻处理,其效果与鲜样24 h内的测定结果较接近;土样不同保存方式以及浸提液的保存时间对3种土壤NH4-N测定结果的影响规律不及NO3-N明显。While it has been demonstrated that soil mineral N（NO3-N and NH4-N） analysis is critical for determining N fertil-izer rate for most field crops,it remains difficult to predict crop N requirement using soil mineral N content due to rapid changes during transportation,pretreatment and storage of soil samples.Proper handling and preserving of soil samples after collection were thus important for the accurate determination of soil mineral N.Analysis fresh soil samples for inorganic N has been rec-ommended,but time constraints had usually require temporary storage of dried or frozen soil samples for later extraction and analysis of soil NO3-N and NH4-N.Meanwhile,2 mol·L-1 KCl and 0.01 mol·L-1 CaCl2（both used as reference extraction regent for soil mineral N） have larger ionic concentrations.2 mol·L-1 KCl has been proven to be beneficial for soil mineral N content stability,but 0.01 mol·L-1 CaCl2 was convenient for confection and has similar ionic strength in soil solutions.In the past sev-eral years,much effort has been devoted to the study of fertilizer N use efficiency.However,information on the fate of N in samples under different preservation methods and acquired for different extraction regent,as well as the effects of soil chemical and physical properties on soil mineral N concentration were lacking.This study investigated the impacts of soil sample extrac-tion and preservation methods on mineral nitrogen content of three types of soil.The ability of two extraction regents（2 mol·L-1 KCl and 0.01 mol·L-1 CaCl2） was assessed.Five preservation methods were evaluated,including no preservation（samples were immediately extracted within 24 h of sample collection）,air-drying,freezing at -19 oC for ten days,and extraction within 24 h and extract liquors frozen at -19 oC for 10 d and 70 d.Ten soil samples（with different fertilization treatments） were collected at 0～20 cm depth from three locations representing different soil types.The content of soil mineral nitrogen was determined using conti

关 键 词：浸提剂 土样保存 浸提液冷冻 硝态氮 铵态氮 

分 类 号：S151.9[农业科学—土壤学]