利用^(15)N自然丰度法区分有机和常规生产的作物  

IDENTIFICATION OF ORGANICALLY AND CONVENTIONALLY PRODUCED CROPS BY NATURAL ^(15)N ABUNDANCE METHOD

作　　者：孟凡乔[1] 诸葛玉平[2] 吴文良[1] 苏志慧[1] 王会[2] 

机构地区：[1]中国农业大学资源与环境学院,北京100193 [2]山东农业大学资源与环境学院,山东泰安271018

出　　处：《核农学报》2011年第6期1300-1305,共6页Journal of Nuclear Agricultural Sciences

基　　金：国家自然科学基金(30970533)

摘　　要：应用15N自然丰度法区分有机和常规生产作物,是近年来国内外氮同位素技术应用研究的热点之一。由于化学合成氮肥和有机肥δ15N的不同,作物产品中相应的δ15N也不同,因此利用作物δ15N判断肥料类型就成为可能。影响作物δ15N的因素,除氮肥类型外,还包括作物的类型、生长阶段、部位、大气沉降、水分、pH以及土地利用方式等。在利用作物15N自然丰度判断氮肥类型过程中,必须特别注意这些因素的综合影响。目前的研究表明,叶菜类、生长期短的作物,生长过程中吸收的氮来源于肥料氮的比例要高于土壤氮,因而利用15N判断使用化肥或有机肥的准确率较高。有机肥中有效N含量越高,越能显著增加植物中的15N含量。化肥和有机肥生产的植物发生δ15N值重叠,主要是由于化肥N通过NH3挥发和反硝化损失进而导致土壤中15 N富集,进而在植物中体现出来。对于氮素在土壤和作物系统中的定量分析,有助于利用作物15N判断氮肥类型。In recent years,the application of natural 15N abundance,for identification of whether crops have been produced organically or conventionally,has attracted significant interest in China and abroad.Since 15N in synthetic and organic nitrogen fertilizers are different,the crops produced on the fertilizers have different 15N levels,which makes identification possible.In addition to nitrogen fertilizer types,crop types,growth stage,sampled part,air nitrogen deposition,water content,pH and land utilization can also influence the fractionation and distribution of 15N in soil-crop system,which should be considered during identification process.This research indicates that for foliar and short growth stage crops,15N identification has higher accuracy than for fruit,root and long growth stage crops.As available nitrogen increases in organic fertilizers,there is a greater possibility of higher 15N in the plant.Overlapping values between organic and chemical fertilized plants are mainly attributed to 15N enrichment of N derived from synthetic fertilizer through N loss via NH3 volatilization and denitrification.Quantitative mass balance analysis of 15N within the soil-crop system can improve the efficiency of 15N identification.

关 键 词：15N 有机作物 氮肥 分馏 

分 类 号：S124[农业科学—农业基础科学]