Simulation of Water Use Improvement Effect in Rain-fed Rice Cultivation in Northeast Thailand

Abstract

For improving the unstable and low production of rain-fed rice in Northeast Thailand, the possibility of application of two kinds of methods was studied using a growth simulation model. In the first method, a watershed area in a patch of the paddy field increased slightly the rice yield per planted area but decreased the total production from the patch of the field. Therefore this method was found to be ineffective for improving rain-fed rice production. In the second method, introduction of direct seeding culture, extended the range of seeding times and enabled to achieve a yield which could not be realized by the transplanting method because of the water shortage for transplanting of seedlings.