【作者】 谷利敏；

【导师】 董树亭； 刘鹏；

【作者基本信息】 山东农业大学 ， 作物栽培学与耕作学， 2014， 博士

【摘要】 华北地区，超量施用氮肥和不合理灌溉导致土壤剖面中和地下水的硝态氮大量积累，降低了氮肥和水分利用效率，限制了经济效益、社会效益和生态效益的提高。为促进该农业生产的可持续发展，亟需建立高产、稳产、优质、低耗、无污染的水氮管理措施。本试验利用大型防雨棚-渗漏池设施，选用不同氮素利用率冬小麦品种（氮高效型品种石麦15和氮低效型品种济麦19），从氮素平衡和水分平衡入手，定量研究了氮水耦合效应（设置不同灌溉量、氮肥类型和施氮量）对小麦玉米周年轮作条件下冬小麦季的氮素流向和利用特性的影响，以期为高产冬小麦氮肥和水分的高效合理利用提供思路和借鉴。主要研究结果如下：1氮水耦合对冬小麦产量的影响两个冬小麦品种石麦15和济麦19的产量和干物质均随氮肥和灌溉投入量的增加而增加。灌溉和氮肥之间存在显著的交互作用，施氮量为180kg N hm-2和90kg N hm-2的产量和干物质之间的差异在胁迫灌溉条件下（W2）显著低于正常灌溉条件下（W1）。相同施氮量条件下，第1年有机肥处理的产量和干物质显著低于尿素处理，随有机肥处理土壤肥力的提高，第3年有机肥处理的产量高于尿素处理。W1条件下，石麦15的产量和干物质均显著高于济麦19，在W2条件下石麦15的干物质高于济麦19，但济麦19的产量高于石麦15。石麦15和济麦19的产量在W1条件下分别比W2条件下高77.2%和41.0%，说明济麦19在水分胁迫条件下减产幅度低于石麦15，其耐旱性比石麦15强。从产量构成因素上分析，增加灌溉量，两品种冬小麦的公顷穗数、穗粒数和千粒重均显著提高，且180kg N hm-2施氮量处理的千粒重和穗粒数均显著高于90kg N hm-2。施氮量相同时，第3年的有机肥处理的千粒重高于尿素处理。品种间的公顷穗数差异明显，石麦15的公顷穗数显著高于济麦19。品种、灌溉量、氮肥类型和施氮量的交互作用显著影响千粒重和产量。2氮水耦合对冬小麦氮素流向的影响植株吸收、氨挥发损失和淋洗损失是土壤氮素的主要流向，2011年分别占投入氮的62.6~195.5%、2.5~25.7%和2.7~25.7，2012年分别占投入氮量54.1~199.9%、5.3~12.6%和5.9~36.5%。增加灌溉量和施肥量，植株吸收氮素和籽粒氮素含量均显著增加。在本试验条件下，施氮量从90kg N hm-2增加到180kg N hm-2，或从灌溉水平从W2提高到W1，植株吸收氮素均显著增加。相同施氮量条件下，尿素处理植株氮素积累量高于有机肥处理，干旱和氮素胁迫促进了氮素向籽粒中的分配。施氮量从90kg N hm-2增加到180kg N hm-2，尿素处理的氨挥发损失量从34.5kg Nhm-2增加到38.3kg N hm-2，增幅11.1%，但氨挥发损失率从41.5%下降到23.0%，降幅44.5%。W2处理的氨挥发速率峰值和累积氨挥发量分别比W1处理的高18.5%和15.4%。尿素处理的氨挥发损失量是有机肥的2.8~3.1倍。不同处理中，W2U1处理的氨挥发损失量最高，达43.8~45.6kg N hm-2，占肥料氮的24.4~25.4%；W2U2处理的氨挥发损失率最高，占肥料氮的40.6~42.5%。逐步回归分析结果表明土壤表层的铵态氮含量和日平均气温与氨挥发速率密切相关，其他因素如氮肥类型、施氮量、土壤pH和灌溉量影响土壤铵态氮含量而间接影响氨挥发速率。W2条件下3年中均无淋洗。W1条件下，第1年无淋洗；第2、3年的淋洗主要发生在生育前期，开花期和灌浆期无淋洗发生，播种期硝态氮淋洗量分别占全年淋洗量的91.1%和56.1%。W1条件下不同施肥处理的硝态氮淋洗在第2、3年分别为3.4~9.1和4.9~12.6kg N hm-2，分别占投入氮量的2.5~7.6%和4.9~12.6%。随施氮量增加，土壤水溶液和淋洗液中的硝态氮浓度增加，但淋洗氮量占投入氮比例降低。淋洗液中硝态氮含量占矿质氮的95.3~97.9%，是主要的淋洗形式。在W1条件下，施肥后土壤增加的硝态氮随着灌溉水的下渗而向下移动，从播种到拔节期，表层硝态氮可以淋洗到200cm处，从开花期到灌溉期可淋洗到100cm处。与尿素相比，尽管有机肥降低了第1、2年硝态氮向下迁移量，但依然会导致硝态氮淋洗。3氮水耦合对冬小麦氮素平衡和氮素利用效率的影响三年后，不同处理之间的有机质含量变化因不同的种植品种、灌溉量、施肥类型和施氮量而异。多数尿素处理的土壤有机质含量呈降低趋势，U1处理的降低量（降低率）高于U2处理；有机肥处理的有机质含量增加，M1与M2土壤有机质增加量（增加率）分别为0.56~2.43g kg-1（5.13~22.35%）和0.06~0.96g kg-1（0.52~8.70%），且在W1条件下有机质的增加量和增加率高于W2条件下。忽略氮肥激发效应和硝化反硝化作用，假定施肥处理的土壤氮矿化量完全等于不施氮处理的氮素输出和投入的差值，有机肥处理表现出氮素盈余，M1的盈余量最高，达109.0~107.7kg N hm-2，占投入氮的30.1~30.2%；而石麦15的尿素处理表现为氮素亏损。三年中，除W1M1、W2M1和W2U1处理的土壤剖面矿质氮含量呈增加趋势外，其他处理的均呈降低趋势。氮水耦合显著影响氮素利用率（Nit-UE）、氮素吸收效率（NUpE）、氮素利用效率（NUtE）和氮素收获指数（NHI）。与W2灌溉相比，W1显著提高了小麦的Nit-UE、NUpE和NUtE，降低了NHI。施氮量从90kg N hm-2增加到180kg N hm-2，小麦的Nit-UE、NUpE、NUtE和NHI降低。相同施氮量时，尿素处理的Nit-UE、NUpE高于有机肥处理，但其NUtE较低。尽管济麦19的Nit-UE显著高于石麦15，但石麦15的植株吸氮量、NUpE和Nit-UE高于济麦19。选用氮高效小麦品种、改施尿素为有机肥、减少播种期的施肥量和灌溉量，可以显著地减少土壤氮素的淋洗和氨挥发损失，增加作物氮素吸收，协同提高小麦的产量和氮素利用率。4氮水耦合对冬小麦水分利用特性的影响W1灌溉条件下0~105cm土层（尤其0~75cm），而W2灌溉条件下0~75cm（尤其0~35cm）土壤含量水量变化最大。W2条件下的水分淋洗量、抽出水量、土壤水分消耗（SWD）和蒸发蒸腾总量（ET）显著地低于W1处理。W2处理的产量水分利用效率（WUEg）和干物质水分利用效率（WUEd）在第1年高于W1处理，但在第3年低于W1处理。冬小麦的水分利用效率随施氮量的增加而增加，但不同施氮量之间WUEg和WUEd的差异在W1条件下显著高于W2处理。水分胁迫降低了氮肥对WUEg和WUEd的促进作用，，施氮可以缓解水分胁迫的产量和水分利用效率负面影响。5氮水耦合对冬小麦叶片光合和衰老特性的影响与尿素相比，施用有机肥可以维持生育后期较高的旗叶抗衰老酶活性和可溶性蛋白含量，延缓叶片衰老进程。增施氮肥可以减轻生育后期旗叶的膜脂过氧化程度，增加光合速率和光合同化物生产，提高冬小麦籽粒产量。胁迫灌溉限制了肥效的发挥，显著降低了冬小麦叶面积指数、光合速率和衰老相关酶活性，导致叶片早衰，产量显著降低。更多还原

【Abstract】 On the North China Plain (NCP), excessive application of nitrogen (N) fertilizer coupledwith unreasonable irrigation has produced high levels of nitrate concentration in surface andgroundwater in agricultural areas, which lowered nitrogen and water use efficiencies (NUEand WUE), and seriously confines the balancing increasement of its economic benefit, socialbenefit and ecological benefit. It is in need of establishing an effective irrigation and nitrogenfertilizer management system conducive to the sustainable development of agriculturalproduction. Based on the wheat-maize cropping system, a lysimeter-rain shelter researchfacility was used to quantitatively study the influence of the rate of N fertilization, type of Nfertilizer, and irrigation level on nitrogen and water use characterastics of different NUEgenetype winter wheat varieties (high NUE genetype variety, shimai15and low NUEgenetype variety, jimai19), water and nitrogen balance in winter wheat production system, toreference for the rational use of nitrogen fertilizer and irrigation. The main results of thisstudy are shown as follows:1Effects of nitrogen and irrigation coupling on grain yieldThe grain yield and dry matter of JM19and SM15were increased with the rate of Nfertilizer and level of irrigation. The interaction of irrigation and N fertilizer has significantlyimpact on grain yield and dry matter of winter wheat. The variance of grain yield and drymatter between high and low rate of N fertilizer under W2irrigation level was smaller thanthat under W1irrigation level. In terms of grain yield and dry matter, values for the manuretreatment were lower than for the urea treatment in season1yet were otherwise higher thanurea treatment in season3. Grain yield of SM15was significantly higher than JM19underW1irrigation, whereas opposite trend under W2irrigation. Dry matter of SM15under both W1and W2irrigation were higher than JM19. This indicates that harvest index of JM19washigher than SM15under W2irrigation. The grain yield of SM15and JM19under W1irrigation level were41.0%and77.2%higher than that under W2irrigation level, thus thenegative effect of water deficit on grain yield of SM15was stronger than JM19. From whichit can be indicated that the drought resistance of SM15was weaker than JM19.The spike number, kernel number and1000grain weight of JM19and SM15wereelevated when the level of irrigation amount increased, and kernel number and1000grainweight of JM19and SM15were elevated obviously when the rate of N fertilizer increased.1000grain weight of both winter wheat varieties of manure treatment was higher than ureatreatment with the same rate of N fertilizer. The effect of N fertilizer type N fertilizer rate onspike number was indistinct. The spike number of JM19was lower than than of SM15.2. EffectS of nitrogen and irrigation coupling on nitrogen flow in wheat fieldCrop uptake, ammonia volatilization, nitrate leaching loss, taking up to54.1~199.9%、2.7~36.5%and2.5~12.6%of imput N, are the main components of N flow after fertilizationapplication in wheat field. With the increasing of level of irrigation and rate of N fertilizer, Nuptake by crop and N accumulation in kernel were increased significantly. However, droughtand N fertilizer deficit promoted the N transportation from stem and leaf to grain.From90to180kg N ha-1urea N applied, the accumulation of AV loss was increasedfrom34.5to38.3kg N ha-1with11.1%improvement, but its proportion of fertilizer appliedwas declined from41.5%to23.0%with44.5%debase. The rate of AV and accumulation ofAV loss under W2irrigation level were18.5%and15.4%higher than that of W1irrigationlevel, respectively. The accumulation of AV loss for urea treatment is approximately2.8-3.1times higher than theat from manure treatment. Among the different treatments, theaccumulation of AV loss of W2U1treatement was the highest one, and reached to43.8~45.6kg N ha-1, taking up to24.4~25.4%of fertilizer N. The proportion of AV loss of W2U2treatement was the highest, and reached to24.4~25.4%of fertilizer N. Rate of AV is directlyrelated to surface soil NH4+-N concentration and average daily temperature. NH4+-Nconcentration in surface soil layer was influenced by type of N fertilizer, rate of N fertilizerand level of irrigation amount.No leaching was observed during three wheat seasons in the W2irrigation treatment, inseason1and after irrigation on anthesis and filling stages in seasons2and3. Most of leachatewas observed during the earlier wheat growth stage, which accounted for91.1and56.1%ofthe total leachate volume in seasons2and3, respectively. Under W1irrigation, the nitrate leaching for different treatments were3.4~9.1kg N ha–1in wheat season2and4.9~12.6kg Nha–1in wheat season3, taking up to2.5~7.6%and4.9~12.6%in season2and3, respectively.The nitrate concentration in soil solution and leachate was elevated with the increasing of rateof N fertilizer, otherwise for the ratio of leached nitrate in the input N. The NH4+-Nconcentration in leachate was very low, and NO3--N was the dominant form of N in leachate,which account from95.3~97.9%of the mineral N. Under W1irrigation, nitrate in soilsolution increased after fertilizer application. The depth of nitrate in surgace soil layer afterirrigation was related to wheat growth season. It could move to200cm during planting stageto jointing stage, and move to100cm during flowering stage to filling stage. Compared tourea, manure fertilization can cause nitrate to leach through2m of soil although the leachingnitrate amount for manure application was lower than that for urea fertilization.3Effect of nitrogen and irrigation coupling on nitrogen balance and useefficiencies of winter wheatAfter three winter wheat-summer maize growth seasons, the change of organic mattercontent of different treatments was varied from wheat variety, irrigation amount, type and rateof N fertilizer. Organic matter content in surface soil was declined for most urea fertilizationtreatments and the declining amount of U1treatment was higher than U2treatment. Organicmatter content in surface soil was improved for all manure fertilization, and the improvedamount and improved ratio for M1and M2treatments were0.56~2.43g kg-1and5.13~22.35%,0.06~0.96g kg-1and0.52~8.70%, respectively. Moreover, these were higherunder W1irrigation condition then W2irrigation. Compared to urea fertilization, manurefertilization increased organic matter content and soil fertility in surface soil. Sufficient watersupply promote the increased of organic matter content in surface soil.When priming effect of nitrogen fertilizer on soil nitrogen and denitrification wereirrespective, and soil mineralization amount was equal to the difference between N output andN input for no fertilizer application treatment, the N input was higher than N output for alltreatments except SW1U1and SW1U2. The imput N was109.0~107.7kg N ha-1higher thanthat output N of M1treatment, taking up to30.1~30.2%of input N. During the three wheatseasons, the mineral N content in2.0m soil profile was increased for treatments of W1M1,W2M1and W2U1. Among which, the increase of W2M1treatment was highest. The mineralN content in2.0m soil profile was decreased for other treatments during3wheat season.Nitrogen and water coupling have an significant impact on nitrogen use efficiency(Nit-UE), nitrogen uptake efficiency (NUpE), nitrogen utilization efficiency (NUtE) and nitrogen harvest index (NHI). Compared to stress irrigation, normal irrigation couldeffectively improve wheat Nit-UE, NUpE, NUtE, however stress irrigation enhanced NHI.Nit-UE, NUpE, NUtE and NHI were decreased when N application evalaved from90to180kg N ha-1. Nit-UE and NUpE of urea were higher than manure treatment, whereas NUtE ofmanure were higher than urea. Although Nit-UE of Jimai19was higher than Shimai15, thecrop nitrogen uptake, NUpE and Nit-UE of Shimai15were higher than Jimai19.Using high N use efficiency wheat variety, substitute urea for manure fertilizer, andreducing the fertilizer and irrigation input on planting stage, are the efficient ways to decreasesoil N losses through leaching and ammonia volatilization, increases crop N uptake, andsynchronously improve wheat yield and N use efficiency.4Effect of nitrogen and irrigation coupling on water use characteristic ofwinter wheatSoil water content changed actively in the surface soil layer, which were0–105cm forW1and0–75cm for W2. Higher variance occurred in the0–75cm layer for W1and in the0–35cm layer for W2. The leaching water amount, extracted soil solution amount, soil waterdepletion (SWD) and wheat evaportranspiration (ET) for W2irrigation treatment weresignificantly lower than W1irrigation treatment. The water use efficiency of grain yield(WUEg) and water use efficiency of dry matter (WUEd) under W2irrigation treatment washigher than W1in wheat season1, but otherwise in wheat seasons2and3. With theincreasing of rate of N fertilizer from90to180kg N ha-1, WUEgand WUEdwas increased.The variance of WUEgand WUEdbetween90and180kg N ha-1was higher under W1irrigation than under W2irrigation. Water deficit could inhibit the positive effect of higher Nfertilizer on grain yield and reduce N use efficiencies. Also, increasing rate of N fertilizercould mitigate the negative impact of water deficit on water use efficiency.5Effect of nitrogen and irrigation coupling on photosynthesis and agingproperties characteristicCompared to urea fertilization, the aging enzyme activity and soluble protein content offlag leaf could maintain at higher level on late winter growth stage for manure fertilization,thus manure fertilization could delay leaf senescence process. In this study, increasing rate ofN fertilizer from90to180kg N·ha-2could ease membrane lipid peroxidation in flag leafduring late wheat growth stage, increased photosynthetic rate, photosynthate and winter wheatgrain yield. Water deficit significantly declined leaf area index, photosynthetic rate, photosynthate and aging enzyme activity, which result in leaf premature aging, early maturityof wheat and obviously lower grain yield.更多还原