温带草甸草原土壤N2O产生过程研究

以大量的室内模拟培养实验,以内蒙古温带草甸草原土壤为研究对象,利用AIM乙炔抑制法,模拟野外条件对原样土壤样品进行N₂O产生过程进行研究。实验结果表明:内蒙古温带草甸草原土壤N₂O产生过程以硝化作用为主。其中异养硝化作用起主导作用,自养硝化潜势和反硝化潜势在草原植物不同生长季节变化不同,总体上异养硝化潜势>自养硝化潜势>反硝化潜势。由于自养硝化作用在不同季节的发生,使得草甸草原土壤N₂O的产生潜势也高、低起伏变化。从而揭示了内蒙古温带草原土壤以异养硝化作用过程为主产生N₂O和N₂O排放通量较低的微生物学机理。

The processes of N2O production in temperate meadow grassland soils

In this paper, A lots of laboratory experiments using the acetylene inhibition method (AIM) were carried to investigate the N₂O production processes in chernozem soil of meadow grassland in Inner Mongolia.The research results showed that the heterotrophic nitrification is the important microbiological process of N₂O production in this kind soil.The potential of autotrophic nitrification and denitrification are different with the changing of grassland vegetation's growing periods.However, the sequence of their contribution is: heterotrophic nitrification > autotrophic nitrification > denitrification.The increasing and decreasing of N₂O production potential result from the appearance of autotrophic nitrification in different growing period.Thereby, the N₂O emission flux from temperate grassland soils was lower because that the heterotrophic nitrification is key N₂O production process in these soils.