Intensive farming rice from two to three crops per year had led to rest of soil between two short - term crops, soil in extendedly reducing conditions, poor aeration and had increase in ability emissions of gases of greenhouse. Practice of alternate wetting and drying technologies had been applied to adapt to the climate change. It did not only contribute to the reduction of production costs, increased environmental sustainability for rice - based, but also reduced greenhouse gases emissions. Objectives of this study were to: determine the effects of alternate wetting and drying on ammoniac and nitrous oxide emissions and evaluate yield performance and water saving strategies of rice cultivated in Vinh Long alluvial soil during winter - spring 2013 - 2014. The field experiment had been established in a randomized complete block design with four replications, treatments including: continuous flooding (CF), alternate wetting and drying (AWD).

Results showed that the peaks of ammonia volatilization and nitrous oxide emissions appeared after 1-2 days of urea application, floodwater pH variation accompanied with timing of nitrogen application. Applying AWD technique resulted in mitigating ammonia volatilization, but nitrous oxide emissions, conversely, was much more as compared to CF. AWD practices saved amount of 1,000 m3 of water per rice crop, but rice yield and nitrogen uptake didn’t reduced. Moreover, the increase of panicle per m2 by AWD applied was noted.