Simulating the Long-Term Effects of Fertilizer and Water Management on Grain Yield and Methane Emissions of Paddy Rice in Thailand

Rice is an important economic crop in Thailand. However, paddy rice fields are one of the largest anthropogenic sources methane (CH4) emissions. Therefore, suitable management practice necessary to reduce CH4 emissions while grain yield maintained. This study aimed evaluate appropriate options fertilizer and water practices for Thai cultivation with regards improving reducing The Denitrification–Decomposition (DNDC) model was used simulate emission under three (chemical (F), manure (M) chemical + (F M)) (continuous flooding (CF), mid-season drainage (MD) alternate wet dry (AWD)) during years 2011–2050. Rain-fed irrigated cropping systems were used. A total 24 sites distributed 22 provinces studied. data sets daily climate, soil properties, required as inputs model. Model validation observation a field experiment indicated that simulated yields (R2 = 0.83, slope 0.98, NRMES 0.30) cumulative seasonal 0.74, 0.43) significantly positively correlated observation. At end simulation period (2046–2050), F M gave more than option by 1–44% rain-fed 104–190% system, respectively. Among options, lower found AWD options. regard maintaining long term suggested be rice, systems.