未来气候条件下秸秆还田和氮肥种类对夏玉米产量及土壤氨挥发的影响

doi:10.3864/j.issn.0578-1752.2023.01.008

摘要/Abstract

摘要：

【目的】秸秆还田配施氮肥可以提高作物生产力，但在气候变化条件下，不同管理措施对夏玉米农田氮素利用存在很大的不确定性。明确在未来气候条件下秸秆还田与氮肥种类对夏玉米产量和土壤氨挥发的影响，以应对气候变化。【方法】利用DNDC模型预测未来不同情景下，秸秆还田和不同氮肥种类对关中地区夏玉米产量和土壤氨挥发的影响。通过田间土壤温度、水分、产量和土壤氨挥发累积量试验数据的验证，DNDC模型可以很好地模拟未来气候条件下不同处理的作物产量和土壤氨挥发累积量。【结果】模拟和实测结果均表明，在当前气候条件下秸秆还田会提高作物产量并促进土壤氨挥发，稳定性氮肥与普通尿素相比对产量无显著影响但会显著减少土壤氨挥发累积量。敏感性分析表明，作物产量与土壤氨挥发累积量均对施氮量最敏感。在RCP4.5排放情景下，单施稳定性氮肥（NF1）和单施尿素（NF2）分别在2050s—2090s和2070s—2090s产量显著降低，秸秆配施稳定性氮肥（SF1）和秸秆配施尿素（SF2）均在2050s—2090s产量显著升高；在RCP8.5排放情景下，单施稳定性氮肥（NF1）在2070s—2090s产量显著降低，单施尿素（NF2）产量无显著变化，秸秆配施稳定性氮肥（SF1）和秸秆配施尿素（SF2）均在2050s—2090s产量显著升高。单施稳定性氮肥（NF1）在RCP4.5排放情景下的2050s—2090s和在RCP8.5排放情景下2030s—2090s土壤氨挥发累积量与当前气候条件相比显著提高，其余各处理在不同排放情景下未来各时期土壤氨挥发累积量与当前气候条件相比均显著降低。【结论】DNDC预测结果表明，在关中地区未来气温和CO₂浓度升高以及降水变化的气候条件下，秸秆还田配施稳定性氮肥会显著提高夏玉米产量并降低土壤氨挥发累积量，是最佳的高产减排农田管理方案，可为应对气候变化及合理使用秸秆和氮肥提供理论基础。

关键词: 秸秆还田, 氮肥种类, 氨挥发, 夏玉米, 产量, DNDC模型, 气候变化, 陕西关中地区

Abstract:

【Objective】 Returning straw to the field and applying nitrogen fertilizer can increase crop productivity. However, under the conditions of climate change, the different management measures have great uncertainty in the nitrogen utilization of summer maize farmland. It is very important to clarify the impact of straw returning and nitrogen fertilizer types on summer maize yield and soil ammonia volatilization under future climate conditions. 【Method】 This study used the DNDC model to predict the impact of returning straw to the field and different types of nitrogen fertilizers on summer maize yield and soil ammonia volatilization accumulation in Guanzhong area under different scenarios in the future. Through the verification of field soil temperature, moisture, yield and soil ammonia volatilization test data, the DNDC model could simulate crop yields and soil ammonia volatilization accumulations under different treatments under the future climate conditions well. 【Result】Both simulation and actual measurement results showed that returning straw to the field increased summer maize yields and promoted soil ammonia volatilization under the current climate conditions. Compared with ordinary urea, slow-release fertilizers had no significant effect on summer maize yield but would significantly reduce soil ammonia volatilization accumulation. Sensitivity analysis showed that both crop yield and soil ammonia volatilization accumulation were the most sensitive to nitrogen application. Under the RCP4.5 emission scenario, the single application of stable nitrogen fertilizer (NF1) treatment and single application of urea (NF2) treatment significantly reduced the summer maize yield in 2050s-2090s and 2070s-2090s, respectively. Both the treatment of straw combined with stable nitrogen fertilizer (SF1) and the treatment of straw combined with urea (SF2) significant increased summer maize yield in 2050s-2090s; under the RCP8.5 emission scenario, NF1 significantly reduced the summer maize yield from 2070s to 2090s, and NF2 showed no significant change. The summer maize yields under SF1 and SF2 were increased significantly from 2050s to 2090s. For NF1 under the RCP4.5 emission scenario in 2050s-2090s and under the RCP8.5 emission scenario 2030s-2090s, the soil ammonia volatilization accumulation significantly increased compared with current climate conditions; for the remaining treatments, the cumulative amount of soil ammonia volatilization in future periods under different emission scenarios would be significantly reduce compared with current climatic conditions. 【Conclusion】The DNDC forecast results showed that under the climate conditions of rising temperature and CO₂ concentration and changing precipitation in the Guanzhong area in the future, the returning straw to the field and applying stable nitrogen fertilizer would significantly increase the summer maize yield and reduce the accumulation of ammonia volatilization in the soil, and it was the best high-yield and emission-reducing farmland management plan. This research provided a theoretical basis for coping with climate change and the rational use of straw and nitrogen fertilizer.

Key words: straw returning, N fertilizer type, ammonia volatilization, summer maize, yield, DNDC model, climate change, Guanzhong area of Shaanxi

赵政鑫,王晓云,田雅洁,王锐,彭青,蔡焕杰. 未来气候条件下秸秆还田和氮肥种类对夏玉米产量及土壤氨挥发的影响[J]. 中国农业科学, 2023, 56(1): 104-117.

ZHAO ZhengXin,WANG XiaoYun,TIAN YaJie,WANG Rui,PENG Qing,CAI HuanJie. Effects of Straw Returning and Nitrogen Fertilizer Types on Summer Maize Yield and Soil Ammonia Volatilization Under Future Climate Change[J]. Scientia Agricultura Sinica, 2023, 56(1): 104-117.

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链接本文: https://www.chinaagrisci.com/CN/10.3864/j.issn.0578-1752.2023.01.008

https://www.chinaagrisci.com/CN/Y2023/V56/I1/104

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参数种类 Parameter type	参数种名称 Parameter name	取值 Value	单位 Note
土壤参数 Soil parameter	土壤质地 Texture	粉质黏壤土 Silly clay loam
	土壤容重 Bulk density	1.40	g·cm^-3
	田间持水量 Field capacity (WFPS)	0.56	g·cm^-3
	孔隙度 Porosity	0.477
	0—10 cm土层有机碳含量 SOC in surface (0-10 cm soil layer)	5	g·kg^-1
	表层土壤NO₃^-含量 Nitrate content in soil suface	2.5	mg·kg^-1
	表层土壤NH₄⁺含量 Ammoium content in soil suface	2	mg·kg^-1
	坡度 Slop	1	°
作物参数 Crop parameter	最高生物量 Max biomass production	4500	kg C·hm^-2·a^-1
	生物量比例 Biomass fraction	0.53/0.18/0.18/0.11	grain/leaf/stem/root
	生物量C/N Biomass C/N ratio	31/60/60/42	grain/leaf/stem/root
	总需氮量 Annual N demand	218.342	kg N·hm^-2·a^-1
	生长积温 TDD	2350	℃
	需水量 Water demand	120	mm
	最适温度 Optimum temperature	30	℃
	固氮系数 Nitrgen fixation index	1

输入参数 Input parameter	基础值 Base value	变化范围 Variation range	产量SI值 SI value of yield				土壤氨挥发SI值 SI value of CAE
输入参数 Input parameter	基础值 Base value	变化范围 Variation range	NF1	NF2	SF1	SF2	NF1	NF2	SF1	SF2
生育期均温 Average temperature during growth period (℃)	23.7	16.59—30.8	0.02	0.02	0.02	0.02	-0.01	0.02	-0.01	0.02
生育期降水量 Precipitation during growth period (mm)	552	386—718	-0.12	-0.10	-0.11	-0.13	-0.01	-0.01	-0.05	-0.04
土壤黏粒含量 Soil clay content (%)	14.0	10—18	0.47	0.39	0.47	0.44	-0.68	-1.08	-0.87	-1.14
土壤有机碳含量 Soil organic carbon content (g·kg^-1)	5	4—7	-0.01	0.01	-0.04	0.01	-0.29	-0.40	-0.43	-0.40
施氮量 Nitrogen application rate (kg·hm^-2)	180	126—234	0.89	0.91	0.67	0.67	1.38	2.53	1.30	2.47
秸秆还田量 Amount of straw returned to the field (kg·hm^-2)	8000	5600—10400	-	-	-0.01	-0.01	-	-	-0.08	-0.08