郭丽,
史建硕,
王丽英^,,
李若楠,
任燕利,
张彦才
河北省农林科学院农业资源环境研究所/河北省肥料工程技术研究中心 石家庄 050051
基金项目: 农业部公益性农业（行业）科研专项201303133
国家重点研发计划专项2016YFD0200401

详细信息

作者简介:郭丽, 主要从事作物栽培学研究。E-mail:guolisoil@163.com

通讯作者:王丽英, 主要从事新型肥料研究与应用工作。E-mail:wangliying5@163.com

中图分类号:S143.3

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出版历程

收稿日期:2017-05-08
录用日期:2017-11-28
刊出日期:2018-05-01

Effects of nitrogen application rate on nitrogen absorption and utilization in summer maize and soil NO₃^--N content under drip fertigation

GUO Li,
SHI Jianshuo,
WANG Liying^,,
LI Ruonan,
REN Yanli,
ZHANG Yancai
Institute of Agricultural Resources and Environment, Hebei Academy of Agriculture and Forestry Science/Hebei Fertilizer Engineering Technology Research Center, Shijiazhuang 050051, China
Funds: This study was supported by the Special Fund for Agro-Scientific Research in the Public Interest of China201303133
the National Key Technology R&D Program of China2016YFD0200401

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Corresponding author:WANG Liying,E-mail:wangliying5@163.com

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摘要
摘要:河北山前平原夏玉米高产区施肥不合理现象普遍存在，农业面源污染严重。研究华北山前平原水肥一体化条件下夏玉米适宜的氮肥运筹，可为该区氮素优化施用技术及提高氮肥利用效率提供依据。本研究以‘郑单958’玉米品种为材料，于2014-2015年2个玉米生长季，在滴灌条件下设置4个施氮水平（N0：不施氮；N1：120 kg·hm^-2；N2：240 kg·hm^-2；N3：360 kg·hm^-2），研究滴灌水肥一体化下施氮量对玉米氮素吸收利用和土壤硝态氮含量的影响。结果表明：N0处理的玉米干物质重及产量较其他处理显著降低，N1、N2和N3处理间无显著差异；N1处理的玉米氮含量和氮累积量较N0处理显著增加，施氮量在N1～N3范围内，不同年份间玉米植株氮含量和氮累积量存在一定差异，总体表现为随施氮量的增加而上升的趋势，但随施氮量的增加，植株氮含量和氮累积量上升幅度逐渐降低。N2处理的氮肥收获指数最高。随施氮量增加，氮肥当季回收利用率、氮肥农学效率、氮肥生产效率和氮肥利用效率显著降低；2014年，在0～100 cm土层范围内，4种施氮处理的土壤硝态氮含量均表现为随土层加深逐渐降低；2015年N2和N3处理的土壤硝态氮在80～100 cm土层达到累积峰，经过2年种植后，年施氮量超过240 kg·hm^-2的处理，土壤硝态氮淋洗加剧。利用一元二次方程拟合产量与施氮量之间的关系，明确了玉米最高产量的施氮量为199～209 kg·hm^-2，经济施氮量为174～187 kg·hm^-2。综合考虑经济效益和生态效益，该条件下夏玉米滴灌水肥一体化的适宜施氮量为174～187 kg·hm^-2。
关键词:滴灌水肥一体化/
夏玉米/
施氮量/
氮素吸收利用/
土壤硝态氮
Abstract:Inappropriate management of fertilizers is common in high-yield summer maize cultivation regions in the piedmont plain of Taihang Mountain, Hebei Province. Fertilizers overuse results not only in serious waste, but also in agricultural non-point source pollution. This study focused on appropriate nitrogen application to support high yield of summer maize under water-fertilizer integration condition. Using 'Zhengdan-958' as the test maize cultivar, four nitrogen rates (N0:no fertilizer; N1:120 kg·hm^-2; N2:240 kg·hm^-2; N3:360 kg·hm^-2 of nitrogen) were set up in 2014-2015 summer maize cultivation seasons under drip fertigation condition. The effects of different nitrogen application rates on the uptake and utilization of nitrogen in summer maize and on nitrate nitrogen content in soil were determined. The results showed that while dry matter weight and yield of maize under N0 treatment significantly decreased, there were no significant differences among N1, N2 and N3 treatments. Nitrogen content and accumulation in maize under N1 treatment significantly increased compared with that under N0 treatment. In the range of N1-N3, nitrogen content and accumulation differed among different years, which increased with increasing nitrogen application rate. However, nitrogen accumulation rate decreased gradually with increasing in nitrogen application rate. Nitrogen harvest index was the highest under N2 treatment among all treatments. Nitrogen recovery efficiency, nitrogen agronomic efficiency, nitrogen productive efficiency and nitrogen use efficiency decreased significantly with increasing nitrogen application rate. In 2014, nitrate nitrogen content under all nitrogen treatments decreased gradually in the 0-100 cm soil layer. In 2015, nitrate nitrogen content in N2 and N3 treatments reached cumulative peak in the 80-100 cm soil layers. This was related to increasing nitrate nitrogen leaching in the soil, which reach down to the 100 cm soil layer when nitrogen rate exceeded 240 kg·hm^-2 during the two years of maize cultivation. Based on the relation between N application rate and yield fitted by one variable quadratic equation, the highest maize yield needed nitrogen application rate in the range of 199-209 kg·hm^-2 and economic nitrogen application rate in the range of 174-187 kg·hm^-2. Considering the ecological environment and economic benefits, the economic nitrogen application rate was the optimal mode for summer maize under drip irrigation condition.
Key words:Drip fertigation/
Summer maize/
Nitrogen application rate/
Nitrogen uptake/
Soil nitrate nitrogen

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图12014年和2015年滴灌水肥一体化下不同施氮量对夏玉米干物质累积量的影响
不同字母表示不同处理差异达5%显著水平。N0:不施氮; N1: 120 kg·hm^-2; N2: 240 kg·hm^-2; N3: 360 kg·hm^-2。
Figure1.Effect of nitrogen application rate on summer maize dry weight accumulation under drip fertigation in 2014 and 2015
Different letters mean significant differences among nitrogen treatments at 5% levels. N0: no nitrogen; N1: 120 kg·hm^-2 nitrogen; N2: 240 kg·hm^-2 nitrogen; N3: 360 kg·hm^-2 nitrogen.


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图22014年和2015年滴灌水肥一体化下施氮量对0～100 cm剖面土壤硝态氮含量的影响
Figure2.Effect of nitrogen application rate on soil NO₃^--N content in 0-100 cm depth soil maize under drip fertigation in 2014 and 2015


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图32014年和2015年滴灌水肥—体化下夏玉米产量与施氮量的关系
Figure3.Relations between yield and nitrogen application rate of summer maize under drip fertigation in 2014 and 2015


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表12014年和2015年滴灌水肥一体化下施氮量对夏玉米植株氮含量及氮累积量的影响
Table1.Effects of nitrogen application rate on nitrogen content and accumulation amount in summer maize under drip fertigation in 2014 and 2015

年份 Year	处理 Treatment	氮含量Nitrogen content (g·kg-1)				?	氮累积量Nitrogen accumulation amount (kg·hm-2)
		拔节期 Jointing	吐丝期 Silking	灌浆期 Filling	成熟期 Maturity		拔节期 Jointing	吐丝期 Silking	灌浆期 Filling	成熟期 Maturity
2014	N0	29.7±1.9c	19.1±0.3c	14.3±0.6c	10.5±1.1c		17.10±0.68b	85.12±4.66c	150.78±3.35c	166.92±6.08c
	N1	36.2±1.3a	23.3±1.7b	18.3±0.5b	12.7±1.3b		26.27±3.53a	123.49±7.69b	233.52±24.03b	250.89±21.57b
	N2	39.4±4.1a	26.2±2.4ab	20.8±0.7ab	14.6±0.5ab		27.95±0.85a	138.53±5.87ab	255.29±8.59a	275.97±8.04a
	N3	39.3±2.9a	29.7±3.0a	21.5±0.7a	15.1±0.8a		25.07±2.96a	158.63±14.91a	259.74±10.42a	276.05±8.33a
2015	N0	25.4±0.7b	14.5±0.6d	12.3±1.6b	9.8±0.9b		12.73±1.60b	71.76±3.03c	123.24±9.14b	176.79±8.96c
	N1	32.5±1.3a	20.2±1.7c	17.2±1.7a	11.4±0.2a		17.86±1.37a	98.52±10.60b	221.41±18.45a	240.43±14.09b
	N2	33.3±1.8a	23.9±1.8b	18.3±0.6a	12.0±1.1a		19.17±2.17a	113.77±4.95a	226.37±16.42a	245.51±21.78b
	N3	34.5±0.6a	27.4±1.7a	18.0±0.5a	12.6±0.6a		19.69±0.82a	118.92±5.50a	227.39±20.18a	274.08±25.33a
同一年份不同字母表示不同处理差异达5%显著水平。N0:不施氮; N1: 120 kg·hm-2; N2: 240 kg·hm-2; N3: 360 kg·hm-2。Different letters for the same year mean significant differences among nitrogen treatments at 5% level. N0: no nitrogen; N1: 120 kg·hm-2 nitrogen; N2: 240 kg·hm-2 nitrogen; N3: 360 kg·hm-2 nitrogen.

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表22014年和2015年滴灌水肥一体化下施氮量对夏玉米籽粒产量和氮素利用效率的影响
Table2.Effects of nitrogen application rate on grain yield and nitrogen use efficiency of summer maize under drip fertigation in 2014 and 2015

年份 Year	处理 Treatment	产量 Grain yield (kg·hm-2)	氮收获指数 Nitrogen harvest index (%)	氮肥当季回收率 Nitrogen recovery Efficiency (%)	氮肥农学效率 Nitrogen agronomy efficiency (kg·kg-1)	氮肥生产效率 Nitrogen productive efficiency (kg·kg-1)	氮肥利用效率 Nitrogen use efficiency (kg·kg-1)
2014	N0	7 831.55b	0.58a				46.96a
	N1	9 969.76a	0.6a	0.61a	24.49a	83.08a	39.87b
	N2	9 562.74a	0.52b	0.45b	7.21b	39.84b	34.62bc
	N3	8 702.62ab	0.48b	0.30b	3.35b	25.10c	31.55c
2015	N0	10 857.63b	0.65a				61.81a
	N1	12 854.77a	0.70a	0.53a	20.64a	107.12a	53.48ab
	N2	12 080.44ab	0.61b	0.29b	5.28b	50.34b	49.33bc
	N3	11 748.25ab	0.55c	0.26b	2.47b	32.63c	43.17c
同一年份不同字母表示不同处理差异达5%显著水平。N0:不施氮; N1: 120 kg·hm-2; N2: 240 kg·hm-2; N3: 360 kg·hm-2。Different letters for the same year mean significant differences among nitrogen treatments at 5% level. N0: no nitrogen; N1: 120 kg·hm-2 nitrogen; N2: 240 kg·hm-2 nitrogen; N3: 360 kg·hm-2 nitrogen.

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表3滴灌水肥一体化下夏玉米产量及氮吸收利用指标间的相关性
Table3.Correlation analysis between yield and indexes of nitrogen absorption and utilization of summer maize under drip fertigation

	施氮量 AON	产量 GY	氮收获指数 NHI	氮当季回收率 NRE	氮肥农学效率 NAE	氮肥生产效率 NPE	氮肥利用效率 NUE	吸氮量 TNU
施氮量AON	1.00
产量GY	0.14	1.00
氮收获指数NHI	-0.65	0.63	1.00
氮肥当季回收率NRE	-0.90**	-0.03	0.49	1.00
氮肥农学效率NAE	-0.92**	0.18	0.68*	0.94**	1.00
氮肥生产效率NPE	-0.92**	0.53	0.91**	0.80*	0.91**	1.00
氮肥利用效率NUE	-0.67*	0.51	0.86**	0.12	0.34	0.67*	1.00
吸氮量TNU	0.89**	0.23	-0.50	-0.47	-0.67*	-0.84**	-0.71*	1.00
*和**分别表示P < 0.05和P < 0.01水平显著相关(双尾检验)。AON: nitrogen application rate; GY: grain yield; NHI: nitrogen harvest index; NRE: nitrogen recovery efficiency; NAE: nitrogen agronomy efficiency; NPE: nitrogen productive efficiency; NUE: nitrogen use efficiency; TNU: total nitrogen uptake. * and ** mean significant correlations at 0.05 and 0.01 levels (2: tailed), respectively.

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