化肥氮对冬小麦氮素吸收的贡献和土壤氮库的补偿  

Contributions of fertilizer N to winter wheat N uptake and compensation of soil N pool in farmland

作　　者：孙昭安 陈清 朱彪[3] 曹慧[1] 孟凡乔 SUN Zhao-an;CHEN Qing;ZHU Biao;CAO Hui;MENG Fan-qiao(College of Biological and Agricultural Engineering,Weifang University/Key Laboratory of Biochemistry and Molecular Biology in University of Shandong,Weifang,Shandong 261061,China;College of Resources and Environmental Sciences,China Agricultural University/Beijing Key Laboratory of Farmland Soil Pollution Prevention and Remediation,Beijing 100193,China;Institute of Ecology/College of Urban and Environmental Sciences/Key Laboratory for Earth Surface Processes of the Ministry of Education,Peking University,Beijing 100871,China)

机构地区：[1]潍坊学院生物与农业工程学院/山东省高校生物化学与分子生物学重点实验室,山东潍坊261061 [2]中国农业大学资源与环境学院/农田土壤污染防控与修复北京市重点实验室,北京100193 [3]北京大学生态研究中心/城市与环境学院/地表过程分析与模拟教育部重点实验室,北京100871

出　　处：《植物营养与肥料学报》2020年第3期413-430,共18页Journal of Plant Nutrition and Fertilizers

基　　金：国家重点研发计划项目(2017YFD0800605-2);潍坊学院博士基金(2019BS12)。

摘　　要：【目的】小麦对氮素的吸收消耗了土壤氮库,土壤中残留的化肥氮则可补偿土壤氮库的消耗,综合考虑这两方面的影响,核算施氮量和秸秆还田对小麦当季土壤氮库盈亏的影响。【方法】收集1980年以来国内报道的小麦15N示踪试验的研究结果,分析化肥氮和土壤氮对小麦当季氮吸收的贡献,小麦当季氮吸收、化肥氮的去向、土壤氮库的盈亏分别与施氮量之间的关系,以及秸秆还田对小麦当季土壤氮库盈亏的影响。【结果】施氮量与化肥氮对小麦当季氮吸收的贡献之间呈显著正相关(P=0.029),而与土壤氮的贡献之间呈显著负相关(P=0.031)。小麦当季氮素吸收源于土壤的比例约为2/3,源于化肥的比例约为1/3,追施氮对小麦氮吸收的贡献约是基施氮的1.5倍。施氮量与氮肥有效率(氮肥利用率+氮肥残留率)之间呈极显著负相关(P=0.004),而与氮肥损失率之间呈极显著正相关(P<0.001)。在秸秆不还田和还田条件下,小麦季土壤氮库的盈亏均与施氮量之间呈极显著正相关(P≤0.001)。【结论】在施氮量为N 60~500 kg/hm^2时,小麦吸收的氮素1/3来自化肥,2/3来自土壤。冬小麦季化肥氮的3个去向为:地上部吸收、土壤残留和损失,其所占比例分别约为36%、33%和31%。在秸秆不还田和还田条件下,土壤氮库达到平衡的施氮量分别为N 308和233 kg/hm^2。【Objectives】This study investigated the effects of chemical fertilizer N and straw returning on the soil N balance in the wheat season,by considering the replenishing effect of residual fertilizer N and straw returning to soil N pool consumption by wheat.【Methods】This study collected the publications on 15N tracer experiments of winter wheat in China since 1980,and analyzed the contribution of chemical fertilizer N and soil N to N uptake by wheat,the relationship between N application rate and N uptake by wheat,the fate of fertilizer N and soil N pool budget,and also investigated the effect of straw returning on soil N pool budget in the wheat season through literature review.【Results】The N fertilizer application rate was significantly and positively related to the proportion of N uptake from fertilizer N in wheat(P=0.029),but significantly and negatively related to the proportion of N from soil N(P=0.031).The ratio of wheat N uptake derived from fertilizer N and soil N was about 1∶2,and the contribution of topdressing N to wheat N was 1.5 times of that of basal N.The N application rate showed significantly negative linear correlations with fertilizer N efficiency(N recovery+N residual rate,P=0.004),and significantly positive linear correlations with N loss rate(P<0.001).Without returning straw or with returning straw to field,there were the significantly positive correlation between soil N pool budget and N fertilizer application rate over the wheat season(P≤0.001).【Conclusions】Within the range of N 60–500 kg/hm^2,the applied fertilizer N in wheat season has three main fates,wheat uptake,soil residue and loss,with ratios in average of 36%,33%and 31%,respectively.The contribution from chemical fertilizer in the nitrogen uptake of wheat is about 1/3,and that from soil is 2/3.The soil N pool could reach balance when N application rate is 308 kg/hm^2 without straw incorporation and 233 kg/hm^2 with straw incorporation,respectively.

关 键 词：冬小麦 氮肥有效率 15N标记 土壤氮库盈亏 化肥氮去向 

分 类 号：S512.11[农业科学—作物学]