Field validation of the DNDC model for greenhouse gas emissions in East Asian cropping systems

Abstract

Validations of the DeNitrification‐DeComposition (DNDC) model against field data sets of trace gases (CH 4 , N 2 O, and NO) emitted from cropping systems in Japan, China, and Thailand were conducted. The model‐simulated results were in agreement with seasonal N 2 O emissions from a lowland soil in Japan from 1995 to 2000 and seasonal CH 4 emissions from rice fields in China, but failed to simulate N 2 O and NO emissions from an Andisol in Japan as well as NO emissions from the lowland soil. Seasonal CH 4 emissions from rice cropping systems in Thailand were poorly simulated because of site‐specific soil conditions and rice variety. For all of the simulated cases, the model satisfactorily simulated annual variations of greenhouse gas emissions from cropping systems and effects of land management. However, discrepancies existed between the modeled and observed seasonal patterns of CH 4 and N 2 O emissions. By incorporating modifications based on the local soil properties and management, DNDC model could become a powerful tool for estimating greenhouse gas emissions from terrestrial ecosystems.