【作者】 梁斌； 赵伟； 杨学云； 周建斌；

【Author】 Liang Bin,Zhao Wei,Yang Xueyxin,Zhou Jianbin (College of Resources and Environmental Sciences,Northwest A & F University,Yangling,Key Laboratory of Plant Nutrition and the Agri-environment in Northwest China,Ministry of Agriculture,Yangling,Shaanxi 712100,China)

【机构】 西北农林科技大学资源环境学院,农业部西北植物营养与农业环境重点实验室；

【摘要】 本试验通过田间微区试验,利用15N同位素示踪法,研究了长期(19年)不施肥(No-F)、长期施用化肥(NPK)和长期有机肥配施化肥(MNPK)对小麦产量、氮素固持与供应、氮肥利用率影响。结果表明,在小麦拔节期,MNPK土壤有15.3%所施入的氮肥被土壤微生物固持,显著高于NPK土壤(12.6%),从小麦拔节期到开花期,MNPK和NPK土壤中分别82%和69%被微生物固持的氮素重新释放出来供作物吸收利用。在No-F土壤中,小麦吸氮量和微生物对氮素固持量都较低,在施肥当季有超过30%所施入的氮肥被淋溶到20cm以下,氮肥利用率仅为20%。在NPK和MNPK土壤中氮素利用率分别为61%和65%。与NPK处理土壤相比,MNPK处理土壤显著提高小麦产量。可见长期有机肥配施化肥可较好协调土壤氮素的供应和作物需氮关系,从而提高小麦产量和氮肥利用率。更多还原

【Abstract】 The aim of this study was to determine if the long-term application of manure,in conjunction with inorganic fertilizers,could improve the synchrony between N supply and crop demand. To test this we applied 15N-labeled urea fertilizer into microplots within three fertilized treatments soil (No-F,no fertilizer;NPK,inorganic NPK fertilization;and MNPK,manure plus inorganic NPK fertilization) of a long-term field trial(1990-2009) under dryland farming.The added N immobilized by microorganisms in the MNPK soil during the early stage of wheat growth was significantly higher than in the NPK soil(12.6%);Of the N immobilized 83%in MNPK and 69%in NPK was released during the elongation and flowering stage of wheat.The 15N use efficiency(NUE) in the No-F soil was only 20%;the majority of 15N remained in soil after harvest.This compared to a NUE of 60.7%and 64.7%in the NPK and MNPK soils,respectively.In comparison with NPK,the MNPK soil had significantly higher(P<0.05) grain yield(11 t ha-1 compared to 9 t ha-1).Our findings highlight that the importance of applying manure with inorganic fertilizers to modulating soil N retention and supply to increase N use efficiency and grain yield while minimizing N loss.更多还原