不同施肥处理对农田土壤有机氮组分及其矿化的影响  

Effects of Different Fertilizers on Organic Nitrogen Fractions and Their Mineralization in Agricultural Soils

作　　者：王乐云 田飞飞 能惠 郑西来[1,2] 辛佳[1,2] WANG Le-Yun;TIAN Fei-Fei;NAI Hui;ZHENG Xi-Lai;XIN Jia(College of Environmental Science and Engineering,Ocean University of China,Qingdao 266100,China;Key Lab of Marine Environmental Science and Ecology,Ministry of Education,Ocean University of China,Qingdao 266100,China)

机构地区：[1]中国海洋大学环境科学与工程学院,山东青岛266100 [2]中国海洋大学海洋环境与生态教育部重点实验室,山东青岛266100

出　　处：《中国海洋大学学报（自然科学版）》2019年第4期117-127,共11页Periodical of Ocean University of China

基　　金：国家自然科学基金重点项目(41731280);国家重点研究发展计划项目(2016YFC0402810)资助~~

摘　　要：有机氮作为土壤中氮的主要存在形式,其各组分对氮矿化贡献程度不同,因此了解有机氮组分及其对氮矿化贡献成为土壤供氮研究的重点。本文通过室内恒温培养法,采用Bremner法测定不同时间土壤中无机氮和有机氮各组分变化,研究不同施肥处理对典型农田土壤有机氮组分及其氮矿化贡献的影响。研究发现,施加尿素促进土壤有机氮矿化,并随着添加量增加矿化作用越强。施加有机粪肥并未显著改变土壤氮的矿化。施加秸秆改变土壤氮素转化的方向,使得固定作用大于矿化作用,土壤出现氮的净固定,并随着添加量增加固定作用越强。通过对有机氮各组分与矿化累积量相关关系分析发现,尿素处理中酸解氨态氮是矿化作用的主要贡献组分,而秸秆处理中酸解未知态氮成为氮矿化的主体。造成有机氮组分对氮矿化贡献的差异主要原因是施肥种类和肥料与土壤的相互作用。综上所述,在实际农业施肥过程中,采用化学肥料与外源有机肥料配施可以有效地提高土壤肥力和改善作物产量。Soil organic nitrogen(SON)in agricultural soils is the dominant form of nitrogen(N),and the different response of their fractions mineralization play a key role in N supply.Therefore,our study aimed to investigate the effects of different fertilizers(urea;manure;straw)on SON fractions and their N mineralization by laboratory incubation experiment in agricultural soils.The SON fractions were determined at different incubation time by the Bremner’s method.The results showed that the effects of three fertilizers on SON fractions and their mineralization were completely different.Urea application facilitated SON mineralization,and the extents of mineralization were enhanced with the increasing application rates.However,adding manure had no significant impact on N mineralization.In addition,straw addition lead to N immobilized,and the extents of immobilization were enhanced with the increasing application rates.Ammonia N was the important substrate of N mineralization in urea-amended soils by correlation analysis between SON fractions and cumulative N mineralization.However,hydrolysable unidentified N became the major N forms in N mineralization with application of straw.The results attributed to the different properties of fertilizers and interactions between soils and fertilizers.Above all,the combination of chemical and organic fertilizers is suggested to be adopted in agricultural practices.

关 键 词：氮肥 氮矿化 有机氮组分 微生物氮 农田系统 

分 类 号：X131.3[环境科学与工程—环境科学]