玉米施用氮肥和有机物N2O释放研究

氧化亚氮(N2O)是除二氧化碳和甲烷之外的一种重要温室气体。N2O通量有明显的季节变化,夏季高于春秋两季;不施肥料及猪粪、秸秆不还田的玉米田N2O排放通量明显高于空地,表明种植玉米促进N2O排放;施用氮肥N2O排放通量在整个玉米生长季均高于不施肥的处理,表明施肥促进土壤N2O排放通量的增加。在施用化肥基础上,玉米秸秆还田、施用猪粪N2O排放通量均高于只施用化肥,在两个排放高峰期表现尤为明显。玉米秸秆、猪粪含有较多的C、N物质,进一步促进了土壤中微生物的硝化和反硝化作用,有利于N2O的生成及排放。在等碳量条件下,施用猪粪N2O排放通量高于玉米秸秆还田;在碳不等量条件下,玉米秸秆还田或猪粪量越高,N2O排放通量越大,表明在一定用量范围内增施有机物料,能增加N2O排放通量。

Study on the Release Mechanism of N2Oin Corn Field Applied Nitrogen Fertilizer and Organic Matter

Nitrous oxide(N₂O) is an important greenhouse gas in addition to carbon dioxide and methane. The N₂Oflux changed obviously with the change of the season. In summer higher than in spring and autumn. Emission amountof N₂Oin corn field with not to fertilizer materials or manure, and straw with not to field was significantly higher thanthe open space. The N₂Orelease in the field can be accelerated by planting corn, applying nitrogen fertilizer. Applyingcorn straw and pig manure can also enhance N₂Orelease flux as the abundant carbon, nitrogen content in it. Under thesame carbon content, the N₂Orelease flux is higher than that in corn straw; under the different carbon contents, theN₂Orelease flux is increased with the increase of corn straw and pig manure concentration.