摘要
本研究以位于山东德州的连续 10 年控释氮肥长期定位试验为平台,在小麦—玉米轮作体系下,试验设置不施氮肥(PK)、农民习惯施肥(FP)、优化施肥(OPT)、控释氮肥(CRF1)和控释氮肥减量 20%(CRF2)5 个处理,分别在玉米抽雄期、灌浆期和小麦拔节期、孕穗期、灌浆期、成熟期采集土壤样品,测定土壤pH值、氮磷钾全量养分、铵态氮、硝态氮、碱解氮含量,测定不同处理玉米、小麦及作物周年产量,以探究长期施用控释氮肥对潮土区麦-玉轮作作物产量的影响及土壤氮素供应特征.结果表明,长期施用控释氮肥可显著提升土壤氮素供应能力,CRF1 处理与OPT处理相比,玉米抽雄期和灌浆期土壤碱解氮含量分别提升 14.10%和9.45%,铵态氮在抽雄期提升125.53%,小麦拔节期铵态氮和硝态氮分别提升63.73%和200.35%.与FP处理相比,CRF1 处理玉米、小麦和周年产量分别显著提高 13.13%、16.73%和 14.89%,而CRF2 处理的产量无显著变化.随机森林模型分析发现,不同施肥模式下玉米产量与灌浆期土壤碱解氮和成熟期土壤全氮含量密切相关,小麦产量则受拔节期土壤硝态氮、孕穗期碱解氮和铵态氮、灌浆期碱解氮以及成熟期土壤全氮、碱解氮含量的综合调控.综上所述,控释氮肥可通过调控氮素释放提高玉米和小麦关键生育期的土壤全氮、碱解氮、硝态氮和铵态氮含量,进而显著提高作物产量,且在减量 20%控释氮肥下仍可保证作物不减产.
Abstract
The long-term positioning test of controlled release nitrogen fertilizer for 10 consecutive years in Dezhou,Shandong Province was used as a platform for this experiment.Five treatments were set as no nitro-gen fertilizer(PK),urea at farmers conventional application rate(FP),urea at optimized application rate(OPT),controlled release nitrogen fertilizer(CRF1)and controlled release nitrogen fertilizer with reduction by 20%(CRF2).Soil samples were collected at the tasseling stage and filling stage of maize,and the jointing stage,booting stage,filling stage and maturity stage of wheat.The soil pH,contents of total nutrients,ammo-nium nitrogen,nitrate nitrogen and alkali-hydrolyzable nitrogen and crop yield were determined in order to ex-plore the effects of long-term application of controlled-release nitrogen on crop yield in wheat-maize rotation system and the supplying characteristics of soil nitrogen in fluvo-aquic soil area.The results showed that long-term application of controlled-release nitrogen fertilizer could significantly improve soil nitrogen supply capaci-ty.Compared with OPT treatment,CRF1 treatment increased the alkali-hydrolyzable nitrogen by 14.10%and 9.45%at maize tasseling stage and filling stage respectively,increased the ammonium nitrogen by 125.53%at tasseling stage,and increased the ammonium nitrogen and nitrate nitrogen by 62.48%and 200.29%respec-tively at wheat jointing stage.Compared with FP treatment,the maize,wheat and annual yields of CRF1 treat-ment increased by 13.13%,16.73%and 14.89%respectively,while the annual yield of CRF2 treatment did not change significantly.Through the random forest model analysis,it was found that the maize yield was closely related to the soil alkali-hydrolyzable nitrogen at filling stage and the total nitrogen at mature stage un-der different fertilization modes,and the wheat yield was comprehensively regulated by nitrate nitrogen at joint-ing stage,alkali-hydrolyzable nitrogen and ammonium nitrogen at booting stage,alkali-hydrolyzable nitrogen at filling stage,and soil total nitrogen and alkali-hydrolyzable nitrogen at mature stage.In summary,controlled release nitrogen fertilizer could increase soil total nitrogen,alkali-hydrolyzable nitrogen,nitrate nitrogen and ammonium nitrogen contents at key growth stages of maize and wheat by regulating nitrogen release,thereby significantly increased the crop yield,and controled no reduction of crop yield under 20%reduction of con-trolled release nitrogen fertilizer.
基金项目
国家重点研发计划项目(2021YFD1901001)
山东省重点研发计划项目(2022SFGC0303)
山东省自然科学基金青年科学基金项目(ZR2021QD033)
山东省农业科学院农业科技创新工程项目(CXGC2022A09)
国家小麦产业技术体系项目(CARS-03)
维普
万方数据