Greenhouse gases emission in rice paddy of South Korea and the effect of flooding management change with RCP 8.5 scenario and adaptation for the scenario.

In 21th century, climate change is one of the fundamental issue. Greenhouses gases are pointed as the most suspicious cause of climate change. Soil play a vital role of carbon sink and also can be a huge source of greenhouse gases defense on the management. The most afraid characteristic of carbon emission in soil is there is feedback between climate change and soil greenhouse gases emission. The first global warming in earth history occurred with the synergy of methane emission and temperature increasing. Methane emission caused global warming and that increased temperature amplified methane emission again. Even major greenhouse gases in this century is carbon dioxide, such a feedback still possible.

Flux of greenhouse gases is not the only factor can be changed by climate change. Climate change can alter proper management. Temperature change will modify crop planting and harvesting date. Other management skills like Fertilizer, manure, irrigation, tillage can also be changed with climate change. Such a management skills changed by climate change can effect to greenhouse gases emission even stronger than temperature change itself.

In this study, greenhouse gases emission in rice paddy in South Korea is simulated with DNDC model from 2011-2100 years. Climate for future is simulated with RCP 8.5 scenario for understanding the effect of climate change to greenhouse gases emission. Various rice paddy flooding techniques were applied to find proper management for future management. With conventional flooding technique, climate change increase greenhouse gases emission highly. Marginal flooding can decrease large amount of greenhouse gases emission and even it still increases with climate change, it has the smallest increasing ratio. If we suppose the flooding technique will change for best grain yield, dominant flooding technique will be different from conventional flooding to marginal flooding. The management change will reduce greenhouse gases emission. The result of study shows the possibility to increase greenhouse gases emission with climate change and climate change adaptation can show apposite result compared without the adaptation.