【作者】 赵健；

【导师】 张忠学；

【作者基本信息】 东北农业大学 ， 农业水土工程， 2020， 硕士

【摘要】 为探究不同水氮管理模式对寒地稻田水、气、土、植株的综合影响,寻找增产、节水、减排的最优水氮管理模式,试验设置了2种灌溉方式（C:控制灌溉、F:常规淹灌）,4种氮肥水平（N0:N0:0 kg/hm²、N1:85kg/hm²、N2:110 kg/hm²、N3:135kg/hm²）,共8组水氮耦合处理。对稻田CH₄和N₂O排放通量进行分析,计算生长季总排放量,估算温室气体排放强度及全球增温潜势,并与水稻根系进行了相关性分析;对土壤理化性质、肥料残留、水稻产量和品质等进行了观测,并建立投影寻踪模型对各项指标进行综合分析。结果表明:1)相同施氮量下,控制灌溉相比于常规淹灌可以降低40.5%～44.1%的CH₄排放量,而对N₂O排放量的影响不显著（P>0.05）。相同灌溉模式下,N₂O的排放量随施氮量的增加而升高,CH₄的排放量随着施氮量的增加先降低后升高。2)控制灌溉相比于常规淹灌,各施氮处理的稻田CH₄和N₂O的综合增温潜势（GWP）降低了35.8%～41.0%。常规淹灌交互零氮肥水平的N₂O排放量最低,控制灌溉交互中等氮肥水平的CH₄排放量最低。8组处理中,CN2处理相较于CN3处理的稻田GHGI没有显著差异（P>0.05）,并具有更小的GWP。3)施氮耦合两种灌溉模式均会导致土壤p H值降低,p H值的降低速率随施氮量的增加而增加,其中FN3处理下降速率最快,平均下降速率为0.023/a。4)施氮耦合两种灌溉模式均会显著提高土壤无机氮含量,且无机氮的累积量随施氮量的增加而增加。5)控制灌溉相比于常规淹灌,各施氮处理的肥料残留量增加了21.7%～46.1%;控制灌溉下肥料残留量随施氮量的增加而增加,常规淹灌下肥料残留量在不同氮肥水平条件下差异不显著。6)相同施氮量下控制灌溉与常规淹灌的水稻产量差异不显著;相同灌溉模式下,水稻产量、淀粉含量和蛋白质含量随施氮量的增加而提高。相同施氮量下控制灌溉相比于常规淹灌,稻米直链淀粉含量提高了4.5%～12.3%;蛋白质有所增加。通过优化后的投影寻踪模型综合分析不同水氮管理下的水稻经济效益和环境效益,最终得到控制灌溉耦合110 kg/hm²氮素配合施用的最优模式,为增产增收、黑土资源的高效利用和水资源的可持续发展提供提供科学的数据分析和理论指导。更多还原

【Abstract】 To explore the comprehensive effects of different water and nitrogen management modes on water,gas,soil and plants in cold paddy fields,to find the best water and nitrogen management model for production increasing,to save water and reduce emissions.The experiment set up two kinds of irrigation methods（C:controlled irrigation,F:flooding irrigation）,and 4 nitrogen fertilizer levels（N0:N0:0 kg/hm²、N1:85kg/hm²、N2:110 kg/hm²、N3:135kg/hm²）,a total8 groups of water and nitrogen coupling treatment.We analyzed the CH4 and N2O emission fluxes from rice fields,calculated total emissions during the growing season,estimated greenhouse gas emissions intensity and global warming potential,made the correlation analysis with rice root system.We observed soil physical and chemical properties,fertilizer residue,rice yield and quality.And then established a projection pursuit model to comprehensively analyze various indicators.The results show that 1)controlled irrigation can reduce CH ₄ emissions by 40.5%～44.1%compare with conventional flood irrigation under the same nitrogen rate.While the effect on N₂O emissions is not significant（P>0.05）.Under the same irrigation mode,N₂O emissions increase with the increase of nitrogen fertilizer level,the emission of CH₄ decrease first and then increase with the increase of nitrogen fertilizer level.2)Controlled irrigation compare with conventional flooding irrigation,the comprehensive warming potential（GWP）of CH₄ and N₂O in paddy fields under each nitrogen treatment decrease by 35.8%～41.0%.Lowest N₂O emissions from flooding couple with 0 nitrogen fertilizer levels.Lowest CH₄ emissions from controlled irrigation couple with moderate nitrogen levels.Among the 8 treatments,there is no significant difference in GHGI between CN2 and CN3（P>0.05）,and CN2 tratement has a lower GWP.3)Both the nitrogen couple with two kinds of irrigation modes result in lower soil p H.The rate of p H decrease increase with the increase of nitrogen fertilizer level.The decline rate of FN3 treatment was the fastest,and the average decline rate was 0.023/a.4)Nitrogen couple with two kinds of irrigation modes significantly increase soil in organic nitrogen content,and the accumulation of inorganic nitrogen increase with the increase of nitrogen fertilizer level.5)Compare with conventional flooding irrigation,the controled irrigation could increase the amount of residual fertilizer by 21.7%～46.1%.The amount of residual fertilizer under controlled irrigation increase with the increase of nitrogen fertilizer level,and the amount of residual fertilizer under conventional flooding irrigation is different,and the difference is not significant.6)There is no significant difference in rice yield between controlled irrigation and conventional flooding irrigation under the same nitrogen fertilizer level.Under the same irrigation model,rice yield increase with the increase of nitrogen fertilizer level.Under the same nitrogen fertilizer level,the amylose content of rice increase by4.5%～12.3%compare with conventional flooding irrigation.Under the same irrigation mode,rice yield increase with the increase of nitrogen fertilizer level.By the optimized projection pursuit model,the economic benefits and environmental benefits of rice under different water and nitrogen management were comprehensively analyzed,and the optimal mode for controlling irrigation coupling 110kg·hm^-2 nitrogen（urea）is obtained,provide scientific data analysis and theoretical guidance for increasing production and income,efficient use of black soil resource and sustainable development of water resource.更多还原