对华北平原小麦-棉花(麦棉)、小麦-大豆(麦豆)、小麦-玉米(麦玉)轮作田的CO2和N2O排放通量进行了测定,分析了温室气体排放通量与土壤中碳、氮元素、气温以及施肥等之间的关系.主要结论:1)麦棉、麦豆、麦玉田的土壤CO2平均排放通量分别为CO2-C 141.7、109.8、128.2 mg·m-2h·-1,其中夏播作物的排放通量高于小麦季;2)麦棉、麦豆及麦玉田作物生长季的土壤N2O平均排放通量分别为N2O-N 98.8、38.9、44.7μg·m-2·h-1,也表现为麦后季作物的排放量高于小麦季;3)同一生育期中不同处理的N2O排放主要与土壤中无机氮含量相关,不同生育期的N2O排放通量主要受不同生育期的土壤温度及水分状况的影响;4)在施肥灌溉后的9 d内土壤N2O排放通量较高,之后逐渐降低,至施肥后22～27d即与不施肥处理的排放持平.%The seasonal variation of CO2 and N2O emission fluxes were measured using closed-chamber method under winter wheat-cotton (WC), winter wheat-soybean (WS), and winter wheat-maize (WM) rotation systems in North China plain.The relationship of emission fluxes of CO2 and N2 O with dissolved organic carbon, soil nitrate, temperature and fertilization were analyzed too. The conclusions were got: 1 ) The average soil CO2 emission flux were CO2 - C 141.7 , 109. 8, 128.2 mg· m-2 · h-1 for WC, WS and WM fields respectively, and the emission flux for the summer sowing crops was higher than that for the spring crops. 2) The average soil N2 O emission flux during rotation period were N2 O - N98. 8, 38. 9,44. 7 μg · m-2 · h-1 during the growing period for WC, WS and WM fields respectively, and the fluxes under summer season also showed higher than that under spring season. 3) The N2O emission of different treatments at the same period was correlated with soil inorganic nitrogen, and it was affected by soil temperature and soil water content under different growing seasons. 4) N2O emission mainly happened during the first 9 d just after fertilization and irrigation, and decreased after that. The N2O emission of fertilization treatments decreased to the same low level with no fertilization treatment after 22 ～ 27 d later since fertilization.
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