EN
Rice is a widely cultivated crop in China and needs a large quantity of water during its entire growth period. Many water-saving irrigation techniques have been developed and widely applied to conserve water in paddy fields in recent years. A controlled and mid-gathering irrigation (CMI) regime is one of them, of which the main feature is to maximize the use of rainwater different from the others. The objective of this study was to assess and verify the water conservation and nitrogen pollution reduction effects of CMI in comparison with a conventional irrigation (CVI) regime. Results showed that the CMI method had potential for water conservation by reducing total irrigation amount and irrigation frequency and making better utilization of rainwater during the rice growth stage. By making use of irrigation water more efficiently, CMI showed higher irrigation water use efficiency and rainfall use efficiency. CMI can also reduce nitrogen pollution emitted to the water system by reducing the pollutant discharge rather than the pollutant concentration during a storm event. However, the irrigation regime’s effect on pollutant loading reduction was not as significant as fertilizer according to experiment results. Thus, the controlled and mid-gathering irrigation regime was favorable for water conservation and reducing emissions of non-point source pollution.