基于产量反应和农学效率的推荐施肥方法在东北春玉米上应用的可行性研究

Availability of fertilizer recommendation for spring maize based on yield response and agronomic efficiency in Northeast China

【目的】针对当前我国玉米生产中肥料不合理施用带来的肥料利用率低的现状,以及我国小农户经营、测土施肥实现困难等问题,建立基于产量反应和农学效率的玉米推荐施肥方法,玉米养分专家系统(Nutrient Expert for Hybrid Maize,NE),研究其在东北春玉米上的应用效果。【方法】于2010~2014年共布置了193个田间试验,从产量、经济和环境方面在东北春玉米种植区对玉米养分专家系统进行校正和改进,包括肥料用量,产量,经济效益,氮(N)、磷(P)和钾(K)肥利用率和氮素损失等方面。试验包括5个处理,分别为农民习惯施肥(FP),玉米养分专家系统的推荐施肥(NE),以及基于NE处理的减氮、减磷和减钾处理。【结果】NE平衡了肥料用量,显著降低了氮肥和磷肥施用量,与FP相比分别降低了43.5(P<0.001)和23.6kg/hm^2(P<0.001),降幅分别达到了21.0%和27.0%,但增加了钾肥用量(8.3 kg/hm^2,P=0.001)。全部试验NE处理产量显著高于FP处理0.6 t/hm^2,增产率为5.2%(P<0.001)。5年平均经济效益(GRF)NE处理比FP处理增加1466 yuan/hm^2,增幅为7.2%(P<0.001),其中1192 yuan/hm^2是通过产量增加带来的,占总增加量的81.3%。NE处理的氮素农学效率(AEN)、氮素吸收利用率(REN)和氮素偏生产力(PFPN)比FP处理平均分别增加了5.8 kg/kg、11.0个百分点和16.8 kg/kg,增幅分别达到了53.8%、47.8%和29.6%;磷素农学效率(AEP)、磷素吸收利用率(REP)和磷素偏生产力(PFPP)平均分别增加了12.3 kg/kg、13.5个百分点和44.0 kg/kg,增幅分别达到了125.9%、87.5%和29.6%;钾素农学效率(AEK)和钾素吸收利用率(REK)平均分别增加了4.0 kg/kg和13.8个百分点,增幅分别达到了30.2%和36.1%,但钾素偏生产力(PFPK)降低了22.4 kg/kg。三年定位试验氮肥施用量NE处理比FP处理共减少102.8 kg/hm^2,地上部氮素吸收量却增加了38.7 kg/hm^2,氮素表观损失降低了78.5 kg/hm^2,收获期土壤氮素残留降低了63.0 kg/hm^2,但NE处理的三年平均产量达到了12.3 t/hm^2,比FP处理平均高0.9 t/hm^2。【结论】近5年,共193个田间试验结果证明,采用基于玉米产量反应和农学效率的推荐施肥方法不仅增加了产量和经济效益,提高了肥料利用率,而且降低了氮素损失,在实践上可以用于我国东北春玉米的施肥推荐。

【Objectives】Low nutrient use efficiency is mianly caused by irrational fertilization.Present fertilizer recommendation technologies based on soil test or plant diagnose are difficult to be used for smallholder farms due to constraints such as access, cost and timeliness in multiple cropping systems. A fertilizer recommendation method, Nutrient Expert for Hybrid Maize（NE）, is established in base of yield response and agronomic efficiency.【Methods】 In this paper, 193 on-farm experiments were conducted in 2010–2014 to validate and optimize the effects of Nutrient Expert for Hybrid Maize from agronomic, economic and environmental aspects on spring maize in the Northeast China. Five treatments were designed in the maize field experiments, including（1）farmers＇ practices（FP）,（2） nitrogen, phosphorous and potassium fertilizer input calculated using NE,（3–5）eliminating nitrogen, phosphorous or potassium input in the NE treatment, which were used for the calculation of nutrient use efficiencies. The grain yield, fertilizer cost, net profit, nitrogen（N）, phosphorus（P） and potassium（K） use efficiency and N loss were investigated at harvest. 【Results】N and P fertilizer input in NE treatment were significantly decreased by 43.5 and 23.6 kg/hm^2 than in FP, about 21.0% and 27% of decrease（P〈0.001）, while K fertilizer input was increased by 8.3 kg/hm^2（P = 0.001）. The grain yields in all the experimental sites were in average 0.6 kg/hm^2 higher in NE than in FP, with the increase rate of 5.2%（P〈0.001）, the averaged gross return was increased by 1466 yuan/hm^2（P〈0.001）, of which, 1192 yuan/hm^2 was from grain increases,accounting for 81.3%. As compared to FP, NE increased agronomic efficiency（AE）, recovery efficiency（RE） and partial factor productivity（PFP） of applied to N by 5.8 kg/kg（＋ 53.8%）、11.0%（＋ 47.8%） and 16.8 kg/kg（＋ 29.6%）, increased AE, RE and PFP of applied to P by 12.3 kg/kg（＋ 125.9%）、13.5%（＋ 87.5%） and 44.0kg/kg（＋ 29.6%）, increased AE and RE of applied to K by 4.0 kg/kg（＋ 30.2%） and 13.7%（＋ 36.1%）, but decreased PFPK by 22.4 kg/kg. Given to three-year total calculated N balance, N fertilizer application in NE was lower than in FP, decreased by 102.8 kg/hm^2, but N uptake in the above-ground in NE was above 38.7 kg/hm^2 than in FP, the high N fertilizer input also led to N accumulation in the soil, the results indicated that the residual N at harvest in 2014 with NE significantly less than with FP, decreased by 63.0 kg/hm^2. Furthermore, totaled 78.5kg/hm^2 of apparent N loss was reduced by using NE than with FP across three-year. However, the yield in NE attained 12.3 t/hm^2,increased by 0.9 t/hm^2 compared with FP. 【Conclusions】In summary, using Nutrient Expert for Hybrid Maize（NE） for fertilizer recommomdation not only increased grain yield, profit and nutrient use efficiency, but also reduced apparent N loss. The Nutrient Expert for Hybrid Maize, which based on yield response and agronomic efficiency, has proved to be a science-based, reliable and feasible method and can be used to make fertilizer recommendation for spring maize in the Northeast China.