| 摘要: |
| 【目的】研究脲醛肥料对土壤N2O排放及氮素去向与平衡的影响，为脲醛肥料的应用提供理论依据。【方法】2013年9-12月，采用微型渗漏计 静态气箱法，在栽培3季不同叶菜（第1季小白菜、第2季菜心、第3季芥菜）的条件下，以不施氮肥为对照，设置3种脲醛肥料（UF1、UF2、UF3，其活性指数（AI）分别为50.8%，67.4%，83.3%）一次性施用、尿素一次性施用、尿素分次施用、脲醛肥料UF2与尿素混合一次性施用共6个处理，研究了脲醛肥料对N2O排放、淋溶损失、土壤残留、植株吸收以及其他表观损失量的影响。【结果】与尿素一次性施用处理相比，无论脲醛肥料AI高低，脲醛肥料一次性施用、脲醛与尿素混合一次性施用和尿素分次施用均能够显著降低N2O排放峰值和累积排放量，各处理N2O气态氮素损失量依次为尿素一次性施用>脲醛与尿素混合一次性施用>尿素分次施用、AI高的UF3一次性施用>AI中和低的UF2、UF1一次性施用，3种脲醛肥料处理的N2O气态氮素损失量为2.32～4.40 g/m2，仅为尿素一次性施用处理N2O气态氮素损失量的33.1%～62.9%。脲醛肥料处理的土壤氮素残留量占总氮量的45%以上，较尿素处理提高了32.1%～34.0%。施用脲醛肥料后减少了氮素淋溶损失量和其他表观损失量，分别较尿素一次性施用处理减少32.6%～54.0%和52.4%～83.9%。脲醛肥料在一次性施用的情况下，植株氮素吸收量等同于尿素分次施用，显著大于尿素一次性施用。【结论】施用脲醛肥料能够明显改变氮素平衡，有利于氮素的植物吸收和土壤残留，而减少氮素的淋溶损失、气态损失及其他表观损失，不仅有利于环境保护，而且有利于提高肥料的利用率。 |
| 关键词: 脲醛肥料 N2O排放 氮素植物吸收 土壤残留 氮素损失 氮素平衡 |
| DOI： |
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| 基金项目:国家自然科学基金项目（31071857，30871594）；广东高校环境友好型肥料工程技术研究中心建设项目（CCZX-A100）；“十二五”国家科技支撑项目（2011BAD11B04）；国家现代农业产业技术体系建设专项（CARS-32） |
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| Effects of urea-formaldehyde fertilizer (UF) on N2O emission and nitrogen balance in soil |
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LI Fei,FAN Xiao-lin
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| Abstract: |
| 【Objective】The effects of urea-formaldehyde fertilizer (UF) on N2O emission and N fate and balance in soil were studied to improve its practical application.【Method】In September to December 2013,micro-lysimeter and static closed chamber was adopted to study the effects of UF on N2O emission,leaching loss,nitrogen (N) residual in soil,N uptake and other apparent losses under three rotations of continuous plant of different leaf-vegetables (Chinese cabbage,flowering cabbage,and mustard).The treatments included three UF levels (UF1,UF2,and UF3 with active indexes (AI) of 50.8%,67.4%,and 83.3%),urea and UF blended with urea,splitting application of urea,and no nitrogen treatment.【Result】Compared with one-time application of urea,one-time application of UF,UF blended with urea,and splitting application of urea significantly reduced N2O emission peak values and cumulative values.Gaseous nitrogen losses from N2O emission were in the order of urea (one-time application)＞UF blended with urea (one-time application)＞urea (splitting application) and UF (high AI,one-time application)＞UF (medium and low AI,one-time application).Gaseous nitrogen losses from N2O emission of UF treatments were 2.32 to 4.40 g/m2,which were 33.1% to 62.9% of the corresponding data of the urea treatment.The N residual in soil of UF treatments was more than 45% of total N applied,32.1% to 34.0% higher than the urea treatment.The N leaching losses and the other apparent N losses of the UF treatments were decreased by 32.6% to 54.0% and 52.4% to 83.9%,respectively.Plant N uptake with one time application of UF equaled to that with urea splitting application,but was significantly greater than that with one-time application of urea.【Conclusion】The application of UF significantly increased N uptake and N residual in soil and reduced N leaching loss,N2O emission,and other N losses.Utilization of UF is an effective measure to protect environment and increase nitrogen use efficiency. |
| Key words: urea-formaldehyde N2O emission N uptake N residual in soil the N leaching loss the balance of N |
