【作者】 史培；

【导师】 郝明德；

【作者基本信息】 西北农林科技大学 ， 生态学， 2011， 硕士

【摘要】 化肥和有机肥料的施用可促进作物对养分以及水分的吸收,提高土壤肥力,增加作物产量。但是不合理的施用方式或肥料的过量施用,增加了土壤CO₂和N₂O温室气体的排放,对肥料施用后温室气体排放的研究,有助于了解温室气体的排放量及其排放规律,为合理施肥提供科学依据。本研究以长武农业生态试验站的长期定位试验为基础,研究了长期施肥对小麦产量、养分吸收特性、CO₂排放、N₂O排放、土壤养分以及土壤水分的影响。试验结果表明:1.在不同降水年型下,合理施肥能大幅增加小麦产量。NPM配施在干旱年、常态年、丰水年分别增产281.74 %、258.89 %、300.0 %,单施M在干旱年、常态年、丰水年分别增产172.43 %、211.11 %、262.22 %。有机肥在促进作物养分吸收量方面的作用显著,NPM配施植株氮、磷、钾的养分平均吸收量最高,在丰水年单施M小麦籽粒吸氮量、吸磷量、吸钾量分别较NP配施提高了84.94 %、84.74 %、40.55 %。2. NPM配施和单施M的土壤有机质含量较不施肥分别增加了56.03 %和51.86 %,有机肥的施用显著增加了土壤有机质含量,NPM配施和单施M的全氮含量无明显差异。NPM配施的全磷和速效磷含量最高,较单施M分别增加了16.25 %和92.69 %,单施M的速效钾含量最高,较NPM配施增加了14.54 %。土壤全氮含量与有机质含量存在极显著的正相关关系,土壤有机质含量与土壤速效磷和速效钾含量均存在显著的正相关关系。不施肥与单施N土壤贮水量最高,在0-80cm土层各处理贮水量变异系数为31 %,随深度的增加贮水量的变异系数减小,NPM配施的水分利用效率最高,较NP配施和单施M分别提高了21.23 %和14.14 %,单施M的水分利用效率是不施肥的1.85倍,是单施N的1.37倍。3.不同施肥措施的土壤耕层有机碳累积量随年份的增加呈不同的变化趋势,2009年较试验初始时NPM配施的土壤耕层有机碳累积量增加了81.88 %,增加幅度最大,NP配施和单施N耕层有机碳累积量随年份的增长无明显的变化趋势,NPM配施和单施M耕层有机碳累积量随年份的增长明显增加,有机肥在促进土壤耕层有机碳累积量增加方面的作用显著。4.土壤CO₂排放具有一定的季节性,冬小麦越冬期土壤CO₂排放通量最低,均处于10 mg CO₂-C·m^-2·h^-1以下的较弱呼吸状况,返青期的土壤CO₂排放通量最高,在16.24³3.90 mg CO₂-C·m^-2·h^-1之间,其中M处理土壤CO₂排放通量最高,为33.90 mgCO₂-C·m^-2·h^-1。单施N与不施肥的土壤CO₂年排放总量差异不显著,单施M和NPM配施时土壤CO₂年排放总量分别为2301 kg CO₂-C·hm^-2和2211 kg CO₂-C·hm^-2,较不施肥分别增加了52.78 %和48.47 %。5. N₂O排放通量在施肥后的0²0天表现出较大差异,肥料的施用对N₂O排放的影响随时间增加而减弱。在萌芽期和出苗期,NPM配施、NP配施和单施N的N₂O排放量远高于其它时期,而单施M和不施肥的N₂O排放量在整个生育期差异不大。NPM配施的N₂O年排放总量,与NP配施和单施N相比分别增加了17.09 %和33.63 %,单施M的N₂O年排放总量为0.21 kg N₂O-N·hm^-2,与不施肥相比N₂O年排放总量差异不大,仅增加了10.67 %。NPM配施N₂O排放系数最高,为0.35 %,NP配施、单施N的N₂O排放系数分别为0.28 %、0.22 %,均基本处于正常的N₂O排放系数范围之间。6. NPM配施与单施M提高了土壤CO₂排放量与土壤各养分含量,NP配施较不施肥土壤CO₂排放量增加,土壤速效钾含量降低,单施N较不施肥降低了土壤CO₂排放量,也降低了土壤全磷及土壤速效养分含量。NPM配施与NP配施提高了土壤N₂O排放量与土壤各养分含量,单施M的土壤N₂O排放量较不施肥无明显差异,土壤养分含量大幅增加,单施N较不施肥明显增加了土壤N₂O排放,在增加土壤养分方面的作用不显著。更多还原

【Abstract】 Applying of chemical fertilizer and manure can promote the absorption for crop to nutrient and water from soil, and improve soil fertility and crop yield. But unreasonable fertilization method or excessive application of fertilizer increase the emission of CO₂ and N₂O from soil, studying on the emission of greenhouse gas after fertilization is useful to understand the emission amount and emission regularity, and these can provide scientific basis for rational fertilization. Based on the long-term fertilization experiment at the Changwu Agro-ecological experimental station, the objective of this work was to study the effect of fertilization on wheat yield, nutrient uptake characters, CO₂ emission, N₂O emission, soil fertility and water.The results showed that:1. Under different precipitation years, rational fertilization can increase the yield greatly. In drought annual, normal annual and wet annual, fertilizer M increased the yield by 172.43 %, 211.11 % and 262.22 % separately; N, P and M applied together increased production remarkably, in drought annual, normal annual and wet annual, fertilizer NPM increased the yield by 281.74 %、258.89 %、300.00 % separately. The application of organic fertilizer can promote the nutrient absorption significantly, the average of N, P, K uptake were highest in NPM treatment, in wet annual, the N, P, K uptake of wheat seed with M fertilizer are 84.94 %, 84.74 %, 40.55 % higher than NP treatment.2. Soil organic matter in M and NPM treatment were 56.03 % and 51.86 % higher than unfertilized plot, the application of organic fertilizer can promote soil organic matter significantly, and there were no significant difference of total N between M and NPM treatment. Total P and available P in NPM treatment were the highest, they were 16.25 % and 92.69 % higher compared to M treatment, available K of M treatment was the highest and 14.54 % higher than NPM treatment. There was obviously positive correlation between total N and organic matter, soil available P and available K were significantly positively correlated with soil organic matter. Soil water storage in unfertilized and N treatment were higher than others, coefficient of variation of soil water storage in 0⁸0 soil layer was 31 % in different treatments, coefficient of variation of soil water storage was decreasing with the increasing depth, water use efficiency of NPM treatment was the highest, it was 21.23 % and 14.14 % higher compared to NP and M treatment, water use efficiency of M treatment was 1.85 times than unfertilized treatment, and 1.37 times than N treatment.3. Soil organic carbon accumulation with year increasing had different variation trend under different fertilizations, in 2009 the soil organic carbon accumulation of NPM treatment was increased by 81.88 % compared to 1984 when the experiment began, the increasing extent of soil organic carbon accumulatiaon in NPM treatment was the largest. With year increasing, the variation trend of soil organic carbon accumulation in NP and N treatment were not obvious, soil organic carbon accumulation in NPM and M treatment had an obvious rising trend, the application of organic fertilizer can increase soil organic accumulation significantly.4. There were seasonal variability of fluxes of CO₂ emission, under different fertilizer application conditions, the fluxes of CO₂ emission were the lowest in over-wintering stage, and they were below 10 mg CO₂-C·m^-2·h^-1, the fluxes of CO₂ emission in regreen stage was the highest and they were between 0.96 and 117.94 mg CO₂-C·m^-2·h^-1, in regreen stage the fluxes of CO₂ emission of M treatment was the highest, and it was 33.90 mg CO₂-C·m^-2·h^-1. The difference of annual emission of CO₂ between unfertilized and N treatment was not significantly, annual emission of CO₂ of NPM and M treatment were 2301 kg CO₂-C·hm^-2 and 2211 kg CO₂-C·hm^-2, and they were 52.78 % and 48.47 % higher than unfertilized treatment.5. There greater differences in the flux of N₂O emission after fertilization 1 to 20 days, the effect of fertilizer on N₂O emission decreased with the increase of time. The amount of N₂O emission in germination and seeding stage were higher than other stages, the amount of N₂O emission of unfertilized and M treatment had not significant difference in the whole growth stage. Compared to NP and M treatment, the annual emission of N₂O of NPM treatment was increased by 17.09 % and 33.63 % separately, the annual emission of N₂O in M treatment was 0.21 kg N₂O-N·hm^-2, and it was 10.67 % higher than unfertilized treatment. Discharge coefficient of N₂O of NPM treatment was 0.35%, and it was the highest, the discharge coefficient of N₂O of NP and M treatment were 0.28% and 0.22%, all of these were within the normal range of discharge coefficient of N₂O.6. The emission of CO₂ and soil nutrient in NPM and M treatment were increased, the emission of CO₂ in NP treatment was increased, available K in NP treatment was decreased, and the emission of CO₂, total P and available nutrient in N treatment were all decreased. The emission of N₂O and soil nutrient in NPM and NP treatment were increased, the difference of emission of N₂O between M and unfertilized treatment was not significantly, soil nutrient in treatment was greatly increased, the emission of N₂O was greatly increased compared to unfertilized treatment, the effect of N treatment on increasing soil nutrient was not significantly.更多还原