通过盆栽模拟试验，探究玉米秸秆生物炭施用对菜地温室气体N2 O、CO2与CH4排放及土壤理化性质的影响。结果表明，生物炭施用抑制了菜地N2O排放，NB1（施N 400 kg·hm－2，生物炭20 t·hm－2）和NB2（施N 400 kg·hm－2，生物炭40 t·hm－2）的N2 O累积排放量分别比N处理（施N 400 kg·hm－2）低76�4％和70�7％，但抑制效应并未随生物炭用量的增加而加强。生物炭施用增强了CO2排放，但对CH4排放影响不显著。 NB1和NB2累积CO2排放量分别为N处理的1�8和2�1倍，不容忽视的是，这2种处理同时增加了土壤中有机碳含量，分别比N处理高15�2％与21�3％。 NB1和NB2在不降低甚至提高蔬菜产量的基础上，提高了土壤中NH4＋⁃N含量与pH值，降低了NO3－⁃N含量。 pH值和NH4＋⁃N含量分别平均比N处理高0�265和34�9％，NO3－⁃N含量平均比N处理低12�7％，因此生物炭具有减排N2 O与改良菜地土壤质量的巨大潜力。但生物炭引起的CO2排放以及对土壤有机碳增加的净影响效应尚需进一步研究。%A pot experiment was carried out to explore impacts of application of maize stalk⁃derived biochar on emissions of nitrous oxide ( N2 O) , carbon dioxide ( CO2 ) and methane ( CH4 ) from and soil physicochemical properties of vegetable fields. Results show that application of the biochar suppressed N2 O emission. Compared to Treatment N ( N 400 kg · hm-2 ) , Treatment NB1 ( N 400 kg·hm-2+ biochar 20 t·hm-2 ) and Treatment NB2 ( N 400 kg·hm-2+ biochar 40 t· hm-2 ) decreased N2 O emission by 76�4% and 70�7%, respectively. But the effect did not increase with increasing appli⁃cation rate of the biochar. Application of the biochar and nitrogen fertilizer promoted CO2 emission, but did not affect much CH4 emission. The cumulative CO2 emission in Treatments NB1 and NB2 was 1�8 times and 2�1 times, respectively, as much as that in Treatment N. Application of the biochar increased soil organic carbon content, which was 15�2% and 21�3% higher, respectively, in Treatments NB1 and NB2 than in Treatment N. Meanwhile, application of the biochar in⁃creased the content of ammonium nitrogen and pH, and reduced the content of nitrate nitrogen while maintaining and even increasing yield of the vegetable. Soil pH and content of ammonium nitrogen was 0�265 and 34�9% higher in the field ap⁃plied with biochar than in the field without application of biochar, while content of nitrate nitrogen was 12�7% lower in the former than in the latter. So biochar has a great potential of decreasing N2 O emission and improving vegetable soil quality. However, it still calls for further study to explore net effect of application of biochar on CO2 emission and soil organic car⁃bon pool.
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