农田土壤N_2O排放研究进展

农田土壤的N2O排放主要是在微生物的作用下通过硝化和反硝化作用产生的。土壤中多变的理化性质影响各种微生物的生长,因而硝化和反硝化过程中产生N2O的途径也不同,尤其以硝化过程的研究进展最快。影响N2O的生成和排放有:土壤含水量、温度、O2以及土壤结构和质地等物理因素,pH和氮肥等其它因素。本文详细地阐述旱地和水田土壤中这些影响因子与N2O的作用机理的差异,及农田土壤中的N2O排放估计的方法。区分硝化和反硝化作用中生成N2O的贡献可用15N标记法和不同浓度的乙炔抑制法。

Research Progress in Nitrous Oxide Emissions from Agricultural Soil

Nitrous oxide can be produced by nitrification and denitrification in agricultural soil. The processes of nitrous oxide producion and emissions are complex under different soil conditions. Physical factors including water content, temperature, oxygen concentration, soil structure, texture, and pH, nitrogen fertilizer and other factors can afleet nitrous oxide producation and emission. (Describing different mechanisms between dry land and paddy field for estimating N2O emissions is benefit for controlling nitrous oxide emission from agricultural soil. ) The contributions of nitrous oxide emissions from nitrification and denitrification is differentiated from ~(15) N labelling method and the technique of different acetylene inhibition.