[Estimation of CO2 and N2O emissions from farmland soils in Hebei Province in Huang-Huai-Hai Plain].

Taking Hebei Province in Huang-Huai-Hai Plain as a study case, the DNDC model was tested with field observation data, and used to estimate the farmlands CO2 and N2O emissions. The results showed that the simulated results could better reflect the characters of soil CO2 and N2O emissions, and the total CO2 and N2O emissions from the farmland soils in 111 counties of Hebei Province in 2003 were estimated to be 3.758 x 10(6) t C and 40.345 x 10(6) kg N, respectively. Winter wheat/ summer maize rotation fields contributed about 40% of the CO2 and N2O emissions, and thus, the mitigation of farmland soil CO2 and N2O emissions should be focused on the high CO2 and N2O emission counties, especially on the winter wheat/summer maize rotation fields in these regions. It could be unnecessary or non-effective to mitigate the CO2 and N2O emissions at large scale.