Contribution of Intermittent Irrigation to Greenhouse Gas Mitigation of Rice Paddy in Hubei Province

In order to grasp the effects of intermittent irrigation on greenhouse gas emission in Hubei province，a database of flooding irrigation and intermittent irrigation greenhouse gas emission from rice field in China was constructed so as to speculate the mitigation factor，and then，estimating the mitigation of intermittent irrigation for 10 years in Hubei province.Results showed that the intermittent irrigation has reduced 1 415.39×104 t CO2-eq GHGs from 2004 to 2013，including 1 039.87×104 t CO2-eq of single-season rice paddy，and 375.52×104 t CO2-eq of double-season rice paddy.Mitigation of different regions were closely associated with area of each type paddy，and also was closely related to mitigation factor.In 10 years，the highest mitigation was found in Jingzhou，with a reduction of 211.14×104 t CO2-eq.Huanggang was the second largest area of mitigated GHGs，about 185.47×104 t CO2-eq.Shennongjia was the least，only 0.054×104 t CO2-eq.Jingzhou was the leading single-season rice GHGs mitigation city，which reached to 159.65×104 t CO2-eq，and Huanggang was the biggest double-season rice GHGs mitigation city，about 115.73×104 t CO2-eq.According to the latest price of Hubei Carbon Trading Market，intermittent irrigation has benefited 354 million yuan from GHGs mitigation alone in past 10 years.Intermittent irrigation as a widely used water-saving irrigation measures，could effectively reduce greenhouse gas emissions，and would not reduce rice production.