A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering, School of Engineering and Technology

Thesis (M.Eng.) - Asian Institute of Technology, 1981

With the aim of developing a cropping calendar which can generate optimum benefits from irrigated rice , a simulation model monitoring farming activities and rice plant responses to water and wind was made for the Philippines. The underlying principle was the equitable distribution of irrigation benefits and optimum crop yield. The model utilizes empirical relations on rice plant responses to moisture stress and wind stress. The model consists of two parts namely (i) the simulation of land soaked area and (ii) simulation of farming activities and rice plant responses to the different climate logical stimuli . Historical data on agrometeorological parameters like temperature , wind, cloudiness, relative humidity, evaporation , rainfall and river flow, together with the cultural practices in the area were used to simulate the three sample systems representing different types of climate. System-wide efficiency was measured in terms of land use efficiency and relative productivity. Tradeoff between reduced total yield due to reduced area and moisture stress on one hand and losses due to wind on the other hand were used in evaluating and developing the cropping calendar which is best suited for the system for optimum benefits. Results of this study prove that a new calendar must be adopted for an improved agricultural economy for the Philippines.