不同耕作施肥方式对稻茬小麦氮素利用及土壤容重的影响

Effects of Different Tillage and Fertilization Methods on Nitrogen Utilization and Soil Bulk Density in Rice-Wheat Rotation System

【目的】探明不同耕作施肥方式对稻茬小麦氮素利用、产量及土壤容重的影响。【方法】以"川麦104"为材料,研究了"免耕-表施肥-稻草盖种(T1)""、免耕-浅施肥-浅旋盖种(T2)""、深翻-深施肥-浅旋盖种(T3)"3种耕作施肥方式对小麦干物质量、氮素积累转运量、土壤容重、硝态氮含量的影响。【结果】与T1、T2相比,T3处理成熟期植株干物质积累量分别提高17.5%和7.3%,植株氮积累量分别提高22.3%和11.5%,小麦开花后营养器官向籽粒的氮转运量分别提高17.5%和11.9%,小麦籽粒产量分别提高26.2%和10.4%,氮肥表观利用率分别提升8.4和6.9个百分点,氮肥偏生产力、农学效率及生理利用率均明显提高;T3处理下,亚表层土壤容重显著降低,总孔隙度明显提高,硝态氮供应能力明显增强。【结论】在试验条件下,综合考虑氮素利用、产量和土壤条件",深翻-深施肥-浅旋盖种"模式为最佳耕作施肥方式,可供生产中参考。

【Objective】The objectives of current study were to explore the effect of different tillage and fertilization methods on nitrogen utilization,wheat yield and Soil bulk density in the rice-wheat rotation system.【Method】‘Chuan Mai 104’being chosen as experimental material,we investigated the effects of three different tillage and fertilization treatment on wheat biomass,nitrogen accumulation and transportation,soil bulk density and nitrate nitrogen content. The three treatments include‘no-tillage+surface application no fertilization+straw-covered seed’(T1),‘no-tillage+upper application no fertilization+shallow-rotary-tillage-covered seed’(T2) and‘deep-plowed +deep application no fertilization+shallow rotation covered’(T3).【Result】Compared with T1 and T2 treatments,T3 treatment has increased the dry matter accumulation by 17.5% and 7.3% respectively,the nitrogen accumulation of plant by 22.3% and11.5% respectively,the nitrogen transport from vegetative organs to grain by 17.5% and 11.9% respectively after anthesis,the grain yield of wheat by 10.4% and 26.2%,and the apparent nitrogen use efficiency by 8.4% and 6.9%respectively. In addition,the partial factor productivity from applied N,agronomical effect and physiological utilization ratio have accelerated significantly under T3 treatment as compared to T1 and T2. Whilst the bulk density has decreased significantly under T3 treatment,conversely to total porosity and nitrate supplying capacity of subsurface soil which were significantly enhanced by T3 treatment,as compared to T1 and T2 treatments.【Conclusion】Based on a comprehensive consideration of nitrogen use efficiency,grain yield and soil condition,we recommend that the deep-plowed+deep application no fertilization+shallow rotation covered should be the best tillage and fertilization method for high yield and beneficial production of wheat in Chengdu plain.