Effect of Controlled-release Nitrogen Fertilizer Combined Urea on Ammonium Nitrogen of Surface Water and Early Rice Yield

doi:10.13304/j.nykjdb.2023.0531

Abstract

Abstract:

The combined application of controlled release nitrogen fertilizer and urea can realize the light and simplified fertilization of rice. In order to study the appropriate amount of nitrogen fertilizer under the combined application of controlled release nitrogen fertilizer and urea in early rice production in red soil area， field plot experiments were arranged. Pure nitrogen 69 （N69）， 104 （N104）， 138 （N138）， 173 （N173） and 207 kg·hm^-2 （N207） were applied according to the combined application ratio of 60% controlled release nitrogen fertilizer and 40% urea， and took no nitrogen application （N0） as control. The rice yield and nitrogen fertilizer agronomic efficiency， as well as the dynamic changes of ammonium nitrogen in surface water after basal fertilizer application were analyzed， and the quantitative relationship between ammonium nitrogen in surface water and rice yield was discussed. The results showed that the controlled release nitrogen fertilizer and urea mixed application could significantly increase rice grain yield （P<0.05）， and with the increase of the amount， rice grain yield increased by 15.6%~30.6%， while the nitrogen fertilizer agronomic efficiency gradually decreased. After the application of controlled release nitrogen fertilizer and urea， the content and total amount of ammonium nitrogen in surface water increased significantly， and reached the peak on the second day after the application of nitrogen fertilizer， and then gradually decreased with time. The content and total amount of ammonium nitrogen in surface water were significantly positively correlated with the amount of controlled release nitrogen and urea applied after fertilization 1~7 d. The slope of the fitting equatio showed that when the nitrogen application rate increased by 1 kg·hm^-2， the content and total amount of ammonium nitrogen in surface water increased the most at 2 d after fertilization， which were 0.06 mg·L^-1 and 1.28 kg·hm^-2. Considering the rice yield and the agronomic use efficiency of nitrogen， it was recommended to control the total nitrogen application rate at 104 kg·hm^-2 in early rice fields in red soil area according to the fixed proportion of 60% controlled release nitrogen and 40% urea. At the same time， avoid drainage at 2 d after fertilization to reduce the loss of nitrogen. Above results could provide technical support for reducing nitrogen application rate and increasing efficiency in early rice production in red soil area.

Key words: controlled-release nitrogen fertilizer combined urea, early rice, yield, surface water, ammonium nitrogen

摘要：

控释氮肥和尿素配施可以实现水稻轻简化施肥，为研究红壤地区早稻生产中控释氮肥和尿素配施下适宜的氮肥用量，通过大田小区试验，按照60%控释氮肥和40%尿素配施比例设置施用纯氮69（N69）、104（N104）、138（N138）、173 （N173）、207 kg·hm^-2（N207），以不施氮肥（N0）为对照，分析各处理的水稻产量和氮肥农学利用率，以及基肥施用后田面水铵态氮的动态变化，探讨田面水铵态氮与水稻产量的量化关系。结果表明，控释氮肥和尿素配施可以显著增加水稻籽粒产量（P<0.05）；随着控释氮肥和尿素配施用量的增加，水稻籽粒产量增加15.6%~30.6%，而氮肥农学利用率则逐渐减少。控释氮肥和尿素配施后，田面水铵态氮含量和总量均显著增加，且均在施入氮肥第2天时达到峰值，然后随着时间推进逐渐降低。施肥后1~7 d，田面水铵态氮含量和总量均与控释氮肥和尿素固定比例混合施用量呈显著正相关，拟合方程斜率表明，当氮肥用量增加1 kg·hm^-2，在施肥后1~7 d，施肥后2 d田面水铵态氮含量和总量的增幅最高，分别为0.06 mg·L^-1和1.28 kg·hm^-2。综合水稻产量和氮肥农学利用率的表现，在红壤地区早稻田推荐按照60%控释氮肥和40%尿素的固定比例将总氮用量控制在104 kg·hm^-2，同时避免施肥后2 d排水，以减少氮肥流失。研究结果为红壤地区早稻生产的氮肥减施增效行动提供技术支撑。

关键词: 控释氮肥和尿素配施, 早稻, 产量, 田面水, 铵态氮

CLC Number:

S511.3⁺1

Yan WU, Leping ZOU, Huijie SONG, Dandan HU, Kailou LIU, Wanli LIANG. Effect of Controlled-release Nitrogen Fertilizer Combined Urea on Ammonium Nitrogen of Surface Water and Early Rice Yield[J]. Journal of Agricultural Science and Technology, 2025, 27(4): 192-200.

吴艳, 邹乐萍, 宋惠洁, 胡丹丹, 柳开楼, 梁万里. 控释氮肥和尿素配施对田面水铵态氮和早稻产量的影响[J]. 中国农业科技导报, 2025, 27(4): 192-200.

Figures/Tables 7

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处理 Treatment	施肥后天数 Days after fertilization/d
处理 Treatment	1	2	3	5	7
N0	1.71±0.12 e	1.98±0.25 e	1.52±0.09 d	1.44±0.07 e	1.15±0.06 e
N69	2.16±0.22 d	6.32±0.17 d	2.32±0.18 c	2.20±0.10 d	4.84±0.10 d
N104	3.05±0.16 c	9.85±0.07 c	9.32±0.14 b	8.62±0.23 c	6.98±0.15 c
N138	3.48±0.31 b	10.82±0.25 b	9.51±0.37 b	9.02±0.35 c	7.66±0.04 b
N173	3.84±0.07 a	10.97±0.16 b	9.86±0.12 a	10.14±0.11 b	7.84±0.08 ab
N207	4.11±0.09 a	12.79±0.14 a	10.14±0.04 a	10.64±0.39 a	7.81±0.10 a

处理 Treatment	施肥后天数 Days after fertilization/d
处理 Treatment	1	2	3	5	7
N0	1.71±0.12 e	1.98±0.25 e	1.52±0.09 d	1.44±0.07 e	1.15±0.06 e
N69	2.16±0.22 d	6.32±0.17 d	2.32±0.18 c	2.20±0.10 d	4.84±0.10 d
N104	3.05±0.16 c	9.85±0.07 c	9.32±0.14 b	8.62±0.23 c	6.98±0.15 c
N138	3.48±0.31 b	10.82±0.25 b	9.51±0.37 b	9.02±0.35 c	7.66±0.04 b
N173	3.84±0.07 a	10.97±0.16 b	9.86±0.12 a	10.14±0.11 b	7.84±0.08 ab
N207	4.11±0.09 a	12.79±0.14 a	10.14±0.04 a	10.64±0.39 a	7.81±0.10 a

处理 Treatment	施肥后天数 Days after fertilization/d
处理 Treatment	1	2	3	5	7
N0	8.57±0.34 e	40.15±0.21 e	22.32±1.17 f	10.66±0.08 e	5.54±0.13 d
N69	11.28±0.35 d	130.86±1.33 d	47.12±1.38 e	34.26±0.17 d	24.48±0.65 c
N104	15.27±0.47 c	198.13±2.21 c	95.57±0.51 d	85.25±1.84 c	34.72±1.36 b
N138	18.42±1.32 b	217.74±3.13 b	111.55±0.49 c	109.12±2.21 b	38.44±1.84 a
N173	19.02±0.66 b	219.34±5.48 b	119.18±1.20 b	111.78±0.95 b	39.38±1.58 a
N207	20.86±0.92 a	254.30±4.99 a	162.59±2.41 a	116.48±2.61 a	49.14±0.20 a

处理 Treatment	施肥后天数 Days after fertilization/d
处理 Treatment	1	2	3	5	7
N0	8.57±0.34 e	40.15±0.21 e	22.32±1.17 f	10.66±0.08 e	5.54±0.13 d
N69	11.28±0.35 d	130.86±1.33 d	47.12±1.38 e	34.26±0.17 d	24.48±0.65 c
N104	15.27±0.47 c	198.13±2.21 c	95.57±0.51 d	85.25±1.84 c	34.72±1.36 b
N138	18.42±1.32 b	217.74±3.13 b	111.55±0.49 c	109.12±2.21 b	38.44±1.84 a
N173	19.02±0.66 b	219.34±5.48 b	119.18±1.20 b	111.78±0.95 b	39.38±1.58 a
N207	20.86±0.92 a	254.30±4.99 a	162.59±2.41 a	116.48±2.61 a	49.14±0.20 a

施肥后天数 Days after fertilization/d	铵态氮含量 Content of ammonium nitrogen			铵态氮总量 Total amount of ammonium nitrogen
施肥后天数 Days after fertilization/d	拟合方程 Fitting equation	R²	P值 P value	拟合方程 Fitting equation	R²	P值 P value
1	y=0.01x+1.70	0.981 2	0.001	y=0.06x+8.14	0.946 8	0.001
2	y=0.04x+4.70	0.763 8	0.014	y=1.28x+40.30	0.975 7	0.001
3	y=0.03x+1.30	0.710 4	0.022	y=0.62x+13.67	0.962 3	0.001
5	y=0.06x+0.80	0.847 7	0.006	y=0.58x+5.55	0.992 7	0.001
7	y=0.04x+1.70	0.889 5	0.003	y=0.16x+5.81	0.984 3	0.001