Re-estimation of direct nitrous oxide emission from agricultural soils of China via revised IPCC2006 guideline method

Nitrous oxide is an important greenhouse gas and agricultural soil is a major source of nitrous oxide emission. The aim of this study was to estimate direct nitrous oxide emissions from agricultural soils of China through the IPCC2006 guideline method updated with combined local parameters and statistical data. The results show that average annual growth rate of direct nitrous oxide emission from agricultural soils of China is 7.6% for 1980~2007, releasing 288 400 tons N in 2007. The contributions of chemical nitrogen fertilizer input, organic material input, crop residues input and histosol soils to direct nitrous oxide emission from agricultural soils of China are 77.64%, 15.57%, 6.46% and 0.33% respectively in 2007. From the distribution pattern, provinces of high nitrous oxide emission are mainly concentrated in North China Plain and Sichuan Basin. On the other hand, provinces of high nitrous oxide emission per unit arable land area are mainly in North China Plain and the Southeast coast area.