To avoid this problem and also save water, instead of keeping fields flooded all the time, some regions (i.e., Philippines) choose to keep the soil near saturation, or apply alternate wetting and drying regimes using intermittent irrigation [46] and [47]. However, it is necessary to differentiate between environments in which rice is grown under flooded conditions. According to Dobermann [48], in relatively fertile lowland environments, growing rice under flooded condition is more sustainable, whereas periodic oxygenation is mainly recommendable on marginal soils that need aeration to improve oxygen supply to the roots so as to avoid toxic concentrations of reduced substances such as ferrous iron (Fe2+) or hydrogen sulfide (H2S) and, consequently, increase yields. This practice would be desirable, but is hardly possible in the lowland soils in the region studied, as the peasants only have a small piece of land to survive and, hence, little potential for applying alternatives for the pre-germinated system. In addition, they have little quantitative information and, therefore, cannot be certain about the effectiveness of the measures they (might) take. However, this problem is not representative for most rice soils in the world. In the case of Asia, for example, more than 75% of the rice is grown on 79 million ha of irrigated land [49] with almost year-long flooding. According to Tuong et al. [49] most irrigated lowland rice ecosystems in Asia have the rainy season as an advantage, when climatic conditions are much more favourable for rice production than for other crops. In conclusion, the yield and performance of flooded rice planted in different countries appear to vary widely due to site-specific characteristics such as climate, soil, water supply, farming practices and socio-economic conditions [48].