西南黄壤性水稻土长期不同施肥模式下作物产量及氮肥利用率演变特征

为了解西南黄壤性水稻土长期施肥效应,通过连续19年长期定位试验,分析了西南黄壤性水稻土单施化肥(NPK)、单施有机肥(M)、1/2有机肥和1/2化肥配施(0.5MNPK)、全量有机肥和全量化肥配施(MNPK)4种施肥模式对作物产量、氮肥利用率的影响及变化特征。结果表明:长期施用化肥或有机肥可显著增加作物产量,NPK、M、0.5MNPK、MNPK比CK分别显著增产56.2%、57.8%、65.0%、74.0%;各施肥处理氮肥偏生产力(PFP_N)、氮肥内部利用率(IE_N)、氮肥回收利用率(RE_N)、氮肥累积利用率(ARE_N)分别为10.9~20.7kg·kg~(-1)、44.7~53.8 kg·kg~(-1)、13.6%~19.6%、12.0%~16.9%,均以0.5MNPK最高,MNPK最低,高量氮肥施用导致氮肥利用率较低;长期单施化肥处理氮肥利用率随时间保持持平或呈下降趋势,施用有机肥的各处理氮肥利用率随时间呈显著上升趋势,尤其是氮肥累积利用率呈极显著上升趋势。长期施用有机肥尤其是有机无机配施作物产量稳定且氮肥利用率稳步提高。因此,常年高量施氮的黄壤性水稻土可适量减少氮肥用量,相应的进行有机无机肥料的合理配施是提高作物产量和肥料利用率的有效措施。

The dynamic of crop yield and nitrogen use efficiency under different long term fertilization patterns in paddy soil from yellow earth in Southwest China

In order to understand the effect of long-term fertilization on dynamics of crop yield,nitrogen use efficiency,five treatments including NPK,M(manure),0.5MNPK(1/2M+1/2NPK),MNPK and CK(no fertilizer)were carried out based on 19 years' long-term fertilizer experiment in paddy soil from yellow field in Guizhou province.The results showed that long-term application of chemical fertilizer or organic fertilizer significantly increased crop yield,the crop yield of NPK,M,0.5MNPK,MNPK treatments were increased by 56.2%,57.8%,65.0%,74.0%,respectively,compared with CK.The partial factor productivity of applied N(PFPN),inner efficiency of applied N(IEN),recovery efficiency of applied N(REN),accumulated recovery efficiency of applied N(AREN)of different fertilization treatments were 10.9~20.7 kg·kg-1,44.7~53.8 kg·kg-1,13.6%~19.6%,12.0%~16.9%,respectively.0.5MNPK treatment had the highest N use efficiency and MNPK had the lowest,which indicated that high N application rate resulted in lower N use efficiency.The different type of N use efficiency of NPK treatment were unchanged or decreased with time,while the N use efficiency in treatments with manure were significantly increased with time,especially the ARE was significantly increased with time.Long-term application of manure,especially manure combined with chemical fertilizers,had stable crop yield and the nitrogen fertilizer utilization rate increased steadily.Therefore,reasonable application of chemical fertilizer coupled with organic manure is an effective measure to improve crop yield,fertilizer use efficiency,and could reduce the amount of N fertilizer in the perennial high amount of paddy soil from yellow field.