Transactions of the Chinese Society for Agricultural Machinery 1000-1298 2019 50 3 262 270 10.6041/j.issn.1000-1298.2019.03.028 article Effects of Oxyfertigation on Soil N2O Emission under Greenhouse Pepper Cropping System 采用水肥氣一體化灌溉可改善土壤的通氣狀況，影響土壤碳氮循環(huán)過(guò)程，進(jìn)而影響土壤N2O的排放。為明確施氮、增氧和灌水對(duì)溫室辣椒地土壤N2O排放的影響，設(shè)置了施氮量（300、225kg/hm2）、溶氧量（40、5mg/L）和灌水量（1.0W、0.6W，W為充分灌溉時(shí)的灌水量）3因素2水平試驗(yàn)，采用靜態(tài)箱-氣相色譜法監(jiān)測(cè)N2O排放通量，系統(tǒng)研究了水肥氣一體化灌溉對(duì)溫室辣椒地土壤N2O排放的影響，并通過(guò)結(jié)構(gòu)方程模型分析各影響因子對(duì)N2O排放的定量貢獻(xiàn)。結(jié)果表明，增氧處理、施氮量和灌水量的增加可增加溫室辣椒地土壤N2O的排放通量峰值、排放總量和單產(chǎn)排放量。試驗(yàn)中增氧條件下N2O排放總量較對(duì)照增加了31.90%；充分灌溉較非充分灌溉增加了43.22%；常量施氮較減量施氮增加了33.01%。增氧處理和灌水量的增加可提高溫室辣椒的氮素利用效率，而施氮量的增加降低了溫室辣椒的氮素利用效率。綜合考慮作物產(chǎn)量、氮素利用效率和單產(chǎn)N2O排放量，減量施氮非充分灌溉增氧處理是推薦的水肥氣管理方案。通過(guò)結(jié)構(gòu)方程模型的路徑分析，土壤溫度、充水孔隙度和NO-3N含量可分別解釋N2O排放的42%、60%和58%，是影響水肥氣一體化灌溉的主要影響因子。 Oxyfertigation delivers water, fertilizer and gas coupled mixture to crop root zone via subsurface drip irrigation system. This new technique changes the oxygen concentration and water distribution in soil and thus affecting the nitrogen cycling process, including nitrification and denitrification, and then affecting soil nitrous oxide (N2O) emissions. However, the influences of oxyfertigation on soil N2O emissions from greenhouse vegetable fields and its main influencing factors were both little known. To understand the influence of aeration, nitrogen application and irrigation on pepper soil N2O emission in greenhouse, totally eight combinations were tested, including two types of nitrogen application rates (300kg/hm2 and 225kg/hm2), two types of aeration levels (40mg/L and 5mg/L), and two types of irrigation amount (1.0W and 0.6W, W was full irrigation amount). Soil N2O emission flux was monitored via using static chambergas chromatograph technique. Soil temperature, waterfilled pore space (WFPS), dissolved oxygen (DO), NO-3N and NH+4N content were also measured. Quantitative contribution of influential factors to N2O emission under oxyfertigation was analyzed by structural equation model (SEM). Results showed that aeration, the increase of nitrogen rate and water amount resulted in an increase of soil N2O emission peak, cumulative N2O emission and yieldscaled N2O emission under oxyfertigation. Compared with control, the cumulative N2O emission of aeration condition was averagely increased by 31.90%. The cumulative N2O emission under full irrigation was averagely increased by 43.22% compared with deficit irrigation. Similarly cumulative N2O emission under conventional nitrogen rate was averagely increased by 33.01% compared with the 75% conventional nitrogen rate treatment. Aeration and the increase of water amount resulted in an increase of crop nitrogen use efficiency. However, the increase of nitrogen rate caused a decrease of crop nitrogen use efficiency. Considering crop yield, nitrogen use efficiency and yieldscaled N2O emission, the treatment of 75% conventional nitrogen rate aerated deficit irrigation was an optimal combination under oxyfertigation. The path coefficients of soil temperature, WFPS and NO-3N content were 42%, 60% and 58%, respectively. And soil temperature, WFPS and NO-3N content were identified as main influential factors. The research result provided a reference for the selection of water, gas and nitrogen coupling management and demonstrated the great significance in knowledge of soil N2O emission under oxyfertigation. 辣椒； 水肥氣一體化灌溉； N2O排放； 增氧； 結(jié)構(gòu)方程模型； 影響因子 pepper; oxyfertigation; nitrous oxide emission; aeration; structural equation model; influential factors 雷宏軍,劉歡,劉鑫,潘紅衛(wèi),陳德立 LEI Hongjun, LIU Huan, LIU Xin, PAN Hongwei and CHEN Deli jcsam/article/abstract/20190328