氮肥运筹对稻茬冬小麦土壤无机氮时空分布及氮肥利用的影响  

Effects of nitrogen fertilization on temporal-spatial distribution of soil inorganic nitrogen and nitrogen utilization in wheat in rice-wheat rotation

作　　者：石祖梁[1] 李丹丹[1] 荆奇[1] 姜东[1] 曹卫星[1] 戴廷波[1] 李建辉[1] 李向楠[1] 陈琳[1] 杜红[1] 赫英俊[1] 

机构地区：[1]南京农业大学农业部南方作物生理生态重点开放实验室,江苏南京210095

出　　处：《生态学报》2010年第9期2434-2442,共9页Acta Ecologica Sinica

基　　金：国家自然科学基金资助项目(30871481);农业部公益性行业科研专项资助项目(200803037)

摘　　要：以宁麦9号和豫麦34号为材料,研究了氮肥基追比对土壤无机氮时空变化、氮素表观盈亏和氮肥利用率的影响。结果表明,施用基肥提高了越冬期0-60 cm土层NO3--N和NH4+-N含量,拔节期追肥对孕穗期各土层无机氮含量无显著影响,追施孕穗肥显著提高了开花期0-60 cm土层硝态氮含量和0-20 cm土层铵态氮含量。不施氮处理各生育阶段均表现为氮素亏缺,施氮处理氮素盈亏呈明显的阶段性,播种至孕穗阶段出现氮素盈余,孕穗至成熟阶段出现氮素亏缺;全生育期氮素表观盈余量两品种平均以5∶5处理最低,7∶3处理最高。两品种氮肥农学效率、氮肥表观回收率和产量均随基肥比例的增加呈先增后降的趋势,均以5∶5处理最高。因此,在小麦生产中应适当减少基施氮肥用量,在小麦拔节孕穗期适当增加追肥比例有利于提高产量和氮肥利用效率,并降低土壤氮素损失。Field experiments with two cultivars of wheat（Triticum aestivum L.cv Ninmai9 cv Yumai34） were conducted in Nanjing during 2006and 2008 to investigate the effects of nitrogen fertilizer regimes on temporal-spatial distribution of soil inorganic nitrogen content,soil nitrogen apparent surplus amount and nitrogen use efficiencies.The results showed that high basal nitrogen fertilizer application rate enhanced NO-3-N and NH＋4-N content in the soil layer of 0-60cm during the period before the start of stem elongation.Topdressing nitrogen fertilizer at jointing did not affect significantly the soil inorganic nitrogen content at booting stage whereas the NO-3-N content of 0-60cm soil layer and NH＋4-N content of 0-20cm soil layer increased at anthesis with the increase of nitrogen fertilizer application rates at booting.Nitrogen deficit occurred throughout wheat growth season in soil without N fertilizer application where apparent N surplus（ANS） was menus.In soil with N fertilizer applications,ANS was positive from sowing to booting,thereafter（from booting till maturity） ANS was menus.During the whole growing season,ANS was averagely the lowest when the basal to topdressing fertilization ratio was at 5∶5 and the highest when the basal to topdressing fertilization ratio at 7∶3.Grain yield,nitrogen agronomic efficiency（NAE） and nitrogen apparent recovery efficiency（NRE） all reached the highest at the basal to topdressing fertilization ratio of 5∶5 and decreased with the basal to topdressing fertilization ratio lower and higher 5∶5.It can be concluded that properly reducing basal nitrogen rate and increasing topdressing nitrogen can improve grain yield and nitrogen use efficiency,hence decreasing soil nitrogen surplus and lose.

关 键 词：冬小麦 氮肥运筹 硝态氮 铵态氮 氮素表观盈亏量 氮肥利用率 

分 类 号：S512.11[农业科学—作物学]