Effects of Nitrogen Fertilizer Level and Planting Density on Changes in Soil Nutrient contents and Nitrogen Use Efficiency in Rice

doi:10.16819/j.1001-7216.2020.9045

Abstract

Abstract:

【Objetive】In order to improve soil fertility, rice grain yield, and nitrogen fertilizer utilization efficiency,【Method】a two-factor field experiment (nitrogen fertilizer level and planting density) was carried out in paddy fields in Rencheng District, Jining City, Shandong Province. The nitrogen application rates were as follows: zero nitrogen (N₁), 0 kg/hm²; low nitrogen (N₂), 216 kg/hm²; medium nitrogen (N₃), 288 kg/hm²; and high nitrogen (N₄), 360 kg/hm², coupling with three planting densities including low density(D₁, 240 000 hill/hm²), medium density(D₂, 270 000 hill/hm²) and high density(D₃, 300 000 hill/hm²). The soil nutrient contents and nitrogen use efficiency were measured in mature stage under different nitrogen fertilizer levels and planting densities. 【Result】The contents of nitrogen, phosphorus, potassium and organic matter decreased significantly with the deepening soil layer. Among them, the content of alkali nitrogen in D₃N₄ treatment decreased by 60.8%, and the content of available phosphorus in D₃N₃ treatment decreased by 72.7%. With the increase of nitrogen application rate, the soil pH and organic matter content decreased, and the available potassium content increased,the partial productivity of fertilizer and nitrogen fertilizer agricultural utilization efficiency decreased, and yield increased first and then decreased. With the increase of planting density, the soil pH and available phosphorus decreased, the alkali nitrogen content of surface soil increased slightly, and the organic matter content, yield and fertilizer partial productivity increased first and then decreased, and the nitrogen agricultural utilization efficiency decreased. 【Conclusion】Under D₂N₃, the rice yield was the highest, reaching 14 615.3 kg/hm². At the same density, the nitrogen fertilizer level of N₂ help give rise to higher rice yield, nitrogen fertilizer agricultural utilization efficiency and fertilizer partial productivity. The research results can be referenced in actual production.

Key words: application level of nitrogen fertilizer, planting density, rice, soil nutrient, yield, fertilizer use efficiency

摘要：

【目的】为解决水稻土壤保肥能力较弱,水稻产量较低,氮肥利用效率不高等问题,【方法】于山东省济宁市任城区水稻田设置氮肥水平与栽植密度双因素大田试验,设4个施氮量水平,即无氮(N₁,0 kg/hm²)、低氮(N₂,216 kg/hm²)、中氮(N₃,288 kg/hm²)和高氮(N₄,360 kg/hm²);栽植密度设3个梯度,即低密度(24万穴/hm²)、中密度(27万穴/hm²)和高密度(30万穴/hm²)。以探究不同氮肥水平和栽植密度下水稻成熟期土壤养分含量及氮肥利用效率的变化。【结果】随着土层加深,氮、磷、钾、有机质含量均明显下降。其中D₃N₄处理碱解氮含量下降了60.8%,D₃N₃处理速效磷含量降低了72.7%。随着施氮量增加,土壤pH值和有机质含量有所下降,速效钾含量升高,肥料偏生产力和氮肥农学利用效率降低,产量先升高后降低;随着栽植密度增加,土壤pH值与速效磷含量有所下降,表层土壤碱解氮含量略有升高,有机质含量与产量及肥料偏生产力均先升高后降低,氮肥农学利用效率降低。【结论】当栽植密度为27万穴/hm²时,氮肥用量288 kg/hm²,水稻产量最高,为14 615.3 kg/hm²;相同密度下氮肥按照216 kg/hm²施用,水稻产量、氮肥农学效率和肥料偏生产力均较高。研究结果可在实际生产中参考应用。

关键词: 氮肥施用量, 栽植密度, 水稻, 土壤养分, 产量, 肥料利用效率

CLC Number:

Siping LI, Lusheng ZENG, Lipeng WU, Yuxiao ZHANG, Junrui XIE, Xiaodong DING. Effects of Nitrogen Fertilizer Level and Planting Density on Changes in Soil Nutrient contents and Nitrogen Use Efficiency in Rice[J]. Chinese Journal OF Rice Science, 2020, 34(1): 69-79.

李思平, 曾路生, 吴立鹏, 张玉晓, 解军蕊, 丁效东. 氮肥水平与栽植密度对植稻土壤养分含量变化与氮肥利用效率的影响[J]. 中国水稻科学, 2020, 34(1): 69-79.

Figures/Tables 9

References 34

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处理 Treatment	土层深度 Soil layer		均值 Average value	变异系数 Coefficient of variation
处理 Treatment	0–20 cm	20–40 cm	均值 Average value	变异系数 Coefficient of variation
D₁N₁	7.72±0.06 b	7.87±0.02 c	7.80	0.014
D₁N₂	7.69±0.01 bc	7.75±0.01 e	7.72	0.005
D₁N₃	7.87±0.06 a	7.99±0.09 ab	7.93	0.011
D₁N₄	7.91±0.05 a	8.03±0.02 a	7.97	0.011
D₂N₁	7.69±0.01 bc	7.98±0.02 ab	7.84	0.026
D₂N₂	7.65±0.04 bcd	7.80±0.02 de	7.73	0.014
D₂N₃	7.63±0.05 cd	7.74±0.06 e	7.69	0.010
D₂N₄	7.59±0.01 de	7.66±0.07 f	7.63	0.006
D₃N₁	7.69±0.03 bc	7.94±0.02 b	7.82	0.023
D₃N2	7.71±0.03 b	7.84±0.01 cd	7.78	0.012
D₃N3	7.54±0.06 ef	7.82±0.03 cd	7.68	0.026
D₃N4	7.51±0.01 f	7.99±0.03 ab	7.75	0.044
氮肥水平Nitrogen level(N)	*	***
栽植密度Planting density(D)	***	***
N×D	***	***

处理 Treatment	土层深度 Soil layer		均值 Average value	变异系数 Coefficient of variation
处理 Treatment	0–20 cm	20–40 cm	均值 Average value	变异系数 Coefficient of variation
D₁N₁	7.72±0.06 b	7.87±0.02 c	7.80	0.014
D₁N₂	7.69±0.01 bc	7.75±0.01 e	7.72	0.005
D₁N₃	7.87±0.06 a	7.99±0.09 ab	7.93	0.011
D₁N₄	7.91±0.05 a	8.03±0.02 a	7.97	0.011
D₂N₁	7.69±0.01 bc	7.98±0.02 ab	7.84	0.026
D₂N₂	7.65±0.04 bcd	7.80±0.02 de	7.73	0.014
D₂N₃	7.63±0.05 cd	7.74±0.06 e	7.69	0.010
D₂N₄	7.59±0.01 de	7.66±0.07 f	7.63	0.006
D₃N₁	7.69±0.03 bc	7.94±0.02 b	7.82	0.023
D₃N2	7.71±0.03 b	7.84±0.01 cd	7.78	0.012
D₃N3	7.54±0.06 ef	7.82±0.03 cd	7.68	0.026
D₃N4	7.51±0.01 f	7.99±0.03 ab	7.75	0.044
氮肥水平Nitrogen level(N)	*	***
栽植密度Planting density(D)	***	***
N×D	***	***

因素分析 Factor analysis	碱解氮 Alkaline nitrogen		速效磷 Available phosphorus		速效钾 Available potassium
因素分析 Factor analysis	0–20 cm	20–40 cm	0–20 cm	20–40 cm	0–20 cm	20–40 cm
氮肥水平Nitrogen level	***	***	NS	***	***	***
栽植密度Density	***	**	***	***	***	***
N×D	***	**	**	***	***	***

因素分析 Factor analysis	碱解氮 Alkaline nitrogen		速效磷 Available phosphorus		速效钾 Available potassium
因素分析 Factor analysis	0–20 cm	20–40 cm	0–20 cm	20–40 cm	0–20 cm	20–40 cm
氮肥水平Nitrogen level	***	***	NS	***	***	***
栽植密度Density	***	**	***	***	***	***
N×D	***	**	**	***	***	***

处理 Treatment	土壤层次 Soil level		均值 Average value	变异系数 Coefficient of variation
处理 Treatment	0–20 cm	20–40 cm	均值 Average value	变异系数 Coefficient of variation
D₁N₁	25.1±1.2 ab	14.7±0.3 de	19.9	0.37
D₁N₂	20.8±2.7 d	18.8±1.1 ab	19.8	0.07
D₁N₃	21.2±0.6 cd	12.7±1.6 e	17.0	0.35
D₁N₄	25.7±0.9 a	16.0±2.0 cd	20.9	0.33
D₂N₁	22.4±0.5 bcd	19.6±0.7 a	21.0	0.09
D₂N₂	25.0±2.8 ab	17.3±1.0 abc	21.2	0.26
D₂N₃	23.7±0.5 abc	17.9±1.8 abc	20.8	0.20
D₂N₄	24.1±0.7 ab	19.0±1.6 ab	21.6	0.17
D₃N₁	23.2±0.5 bc	16.7±0.4 bcd	20.0	0.23
D₃N₂	24.8±1.9 ab	16.2±0.5 cd	20.5	0.30
D₃N₃	22.6±2.7 bcd	16.8±1.9 bcd	19.7	0.21
D₃N₄	22.9±0.3 bc	12.9±2.3 e	17.9	0.40
氮肥水平Nitrogen level(N)	*	***
栽植密度Planting density(D)	NS	*
N×D	**	***