不同土壤肥力条件下施氮量对小麦氮肥利用和土壤硝态氮含量的影响  

Effects of nitrogen rate on nitrogen fertilizer use of winter wheat and content of soil nitrate-N under different fertility condition

作　　者：赵俊晔[1] 于振文[1] 

机构地区：[1]山东农业大学农业部小麦栽培生理与遗传改良重点开放实验室

出　　处：《生态学报》2006年第3期815-822,共8页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(30471026);国家"十五"科技攻关资助项目(2002BA516A12)~~

摘　　要：在土壤肥力不同的两块高产田上,利用15N示踪技术,研究了高产条件下施氮量对冬小麦氮肥吸收利用、籽粒产量和品质的影响,及小麦生育期间土壤硝态氮含量的变化.结果表明：1.成熟期小麦植株积累的氮素73.32%～87.27%来自土壤,4.51%～9.40%来自基施氮肥,8.22%～17.28%来自追施氮肥;随施氮量增加,植株吸收的土壤氮量减少,吸收的肥料氮量和氮肥在土壤中的残留量显著增加,小麦对肥料氮的吸收率显著降低;小麦对基施氮肥的吸收量、吸收率和基施氮肥在土壤中的残留量、残留率均显著小于追施氮肥,基施氮肥的损失量和损失率显著大于追施氮肥;较高土壤肥力条件下,植株吸收更多的土壤氮素,吸收的肥料氮量较少,土壤中残留的肥料氮量和肥料氮的损失量较高,不同地块肥料氮吸收、残留和损失的差异主要表现在基施氮肥上.2.当施氮量为105 kg/hm2时,收获后0～100cm土体内未发现硝态氮大量累积,随施氮量增加,0～100cm土体内硝态氮含量显著增加;施氮量大于195 kg/hm^2时,小麦生育期间硝态氮呈明显的下移趋势,土壤肥力较高地块,硝态氮下移较早,下移层次深.3.随施氮量增加,小麦氮素吸收效率和氮素利用效率降低,适量施氮有利于提高成熟期小麦植株氮素积累量、籽粒产量和蛋白质含量;施氮量过高籽粒产量和蛋白质含量不再显著增加,甚至降低;较高土壤肥力条件下,获得最高籽粒产量和蛋白质含量所需施氮量较低.Application of nitrogen （N） fertilizer is one of the most important measures that increase grain yield and improve grain quality of winter wheat （ Triticum aestivum L. ）. However, it is common that excessive N fertilizer is applied on high fertility field, which not only causes the decline of N use efficiency and economic effects, but also results in larger amount of nitrate-N accumulated in soil, and so it is concerned to bring potential risk to environment. This research was conducted to determine the effects of N fertilizer rate on N fertilizer use, grain yield and quality of winter wheat, and changes in soil nitrate-N content during wheat growth period under high-yielding conditions. The results will help to choose optimum N rate, to obtain profitable yields, efficient N use, and reduce the possible impact on environment. The experiments were carried out in two high-yielding fields, differed in soil fertility in Qianzhuliu, Longkou, Shandong,China, during 2002-2003. Seven N treatments （CK1, CK2, N1, N2, N3, N4, N5） were designed, with the N rate of 0, 0, 105, 150, 195,240, 285 kg/hm^2 ,respeetively. The N fertilizer was urea. Half of the N fertilizer was applied before sowing, and the other was topdressed at jointing stage. Apart from the treatment of CKI, all the other 6 treatments were supplied with 135 kg P2O5/hm^2 and 105 kg K2O/hm^2 before sowing. Each treatment had 3 replicates, with a plot of 3m×8m. In the field plots of N1, N3, N4 treatments, microplots of 15N traeing experiments were set, with the area of 15cm×44.5cm, and isolated with a 30cm high iron frame. Each 15N microplot had 2 replicates, which was added with 10.13 atom % 15 N-urea before sowing or topdressed. The rate and date of N application in the microplots were the same to these in the field plot. Wheat was sowed on Oetober 8 in 2002, with plant density of 120/m^2. The results showed that 73.32%-87.27 % N accumulated in wheat plant at mature stage was derived from soil, 4.51%-9.40% from basal N fertilizer, and 8.22%-17.2

关 键 词：施氮量 土壤肥力 冬小麦 氮肥利用 土壤硝态氮 产量 

分 类 号：S512.1[农业科学—作物学]