摘要
【目的】在"化肥零增长"的背景下评估冬油菜氮肥减施潜力,为我国油菜产业高产高效的协同发展提供科学依据。【方法】本研究通过分析统计数据(2005~2014年)、文献数据(2000年至今)以及油菜施肥(2005~2015年)和调查数据(2009~2011年),定量研究了国内外油菜产量与氮肥偏生产力的差距,明确了我国冬油菜各主产省份氮肥推荐水平较农户水平的节氮空间,同时利用QUEFTS模型探讨了未来不同情景模式下我国冬油菜的节氮潜力。【结果】统计数据显示,近十年我国油菜产量接近于世界平均水平(1800 kg/hm^2),冬油菜产量集中在1500~2100 kg/hm^2,但远低于发达国家,且年均产量增幅较低。调查数据显示,国内农户水平施氮量普遍偏高,平均为188 kg/hm^2,结合我国冬油菜种植面积(6238×10~3 hm^2)和推荐水平施氮量(平均162kg/hm^2),全国冬油菜氮素投入量可节省16.0×10~4 t,可节氮的主要省份为湖南、江苏、湖北、四川。其中,湖南、江苏节氮主要由于单位面积节氮空间较大,湖北和四川则因种植面积大而获得较大的节氮空间。分别以不施氮处理油菜吸氮(N)量30、50、70 kg/hm^2(相当于油菜产量约为500、1000、1500 kg/hm^2)划分为低、中、高三个土壤供氮水平。在农户氮肥偏生产力水平(PFP_N,10.9 kg/kg)的基础上,设置推荐水平为情景Ⅰ,PFPN依次增加5个单位分别为情景Ⅱ(国外一般水平)、情景Ⅲ(国外中等水平)、情景Ⅳ(国外较高水平),分析不同情景的冬油菜节氮潜力。结果显示,在低供氮条件下,当目标产量超过2500 kg/hm^2时,至少达到情景Ⅱ(国外一般水平)时才有节氮空间;而在中、高等供氮条件下,达到不同目标产量时均有一定的节氮空间。【结论】依据土壤基础供氮能力和油菜目标产量进行氮肥管理,并结合其他农艺管理措施,是实现油菜高产、氮肥减施增效的重要途径。
【Objectives】Evaluation of nitrogen fertilizer saving potential in oilseed rape under the national plan of zero growth in chemical fertilizers would be meaningful for the development of high yield and high efficiency for oilseed rape production.【Methods】The statistical dataset(2005–2014),literature dataset(after 2000),fertilization dataset(2005–2015) and investigation dataset(2009–2011) were combined in our study for quantifying the oilseed rape yield gap and partial factor productivity of nitrogen(PFPN) gap in domestic and abroad and determining the nitrogen saving potential of recommended level compared to farmers' level in the major winter oilseed rape producing provinces.The nitrogen saving potential of winter oilseed rape under the different scenarios in the future was explored using the Quantitative Evaluation of the Fertility of Tropical Soils(QUEFTS) model.【Results】The statistical results showed that oilseed rape yield in China was approximate with that in the world(1800 kg/hm^2) in the past ten years,and winter oilseed rape yields were mainly from 1500 to2100 kg/hm^2,but lower than those in Europe.The national yield increase was at a low level,and appeared to yield stagnation.The investigation results showed that the nitrogen rates at the farmers' level were generally higher with an average of 188 kg/hm^2.Combination of the planting area(6238×103 hm^2) and recommended nitrogen rate(162 kg/hm^2) for winter oilseed rape,the nitrogen saving potential was calculated,i.e.16.6×104 t.And the main nitrogen saving provinces were Jiangsu,Hunan,Hubei,and Sichuan.Considering that soil indigenous nitrogen supply(INS) is a critical factor for the yield potential and nitrogen saving potential,the N supply levels were divided into low,middle and high according to the nitrogen uptakes of the nitrogen omission treatments of N 30,50 and 70 kg/hm^2(corresponding yields were about 500,1000 and 1500 kg/hm^2),respectively.On the basis of farmers' level,the recommendation level was set as the scenario Ⅰ,and PFPN amounts increased by every 5 units were set as the scenarios Ⅱ(foreign normal level),Ⅲ(foreign medium level),and Ⅳ(foreign high level).The result showed that nitrogen demand was improved by increasing target yield,and the increment was growing bigger.Under the low level of INS and the target yield was more than 2500 kg/hm^2,nitrogen rate could be saved only when the foreign normal level was reached.Under the middle or high levels of INS,nitrogen saving capacity was sufficient when different target yields were achieved.【Conclusions】Combination of INS,target yield of oilseed rape and other agricultural measures was crucial for accomplishing high yield,high efficiency and nitrogen saving.
出处
《植物营养与肥料学报》
CAS
CSCD
北大核心
2017年第6期1494-1504,共11页
Journal of Plant Nutrition and Fertilizers
基金
国家重点研发计划项目(2016YFD0200108)
国家油菜产业技术体系建设专项(CARS-13)
中央高校基本科研业务费专项资金(2662016PY117)资助
关键词
冬油菜
产量差
氮肥偏生产力
情景分析
QUEFTS模型
winter oilseed rape
yield gap
partial factor productivity of nitrogen
scenario analysis
QUEFTS model