Paper Title
The Parameters Study on Rice Growth Simulation For Fertilizer Management in Acid Soil Paddy Rice

Rice is one of staple foods for human and serving for the world�s population. Although global production has excess demand in the last 20 years, food security problems still facing and need to be manage based on early and reliable recommendation for all activities of paddy rice. The important attempt for manage and prediction the rice crop yield based on simulation models was developed. However, sample of operation systems implementing models is suitable for reproducing the peculiarities of paddy rice, especially on site-specific or small rice farm was missing recognize such as in acid soil area, In this study Oryza2000was used for evaluation and optimum fertilizer in acid soil paddy rice. The experiment was based on acid soil paddy field in two district name Bangkha and Banpho district of Chachoengsoa province Thailand. The most relevant model parameter was identified through sensitivity analysis carried out using the manually and calibrated using linear model method. The data from published experiments in 2 locations and 3 years were used. Our result from new framework was able to report a optimum parameters with Oryza2000 in case fertilizer management at both districts. Specifically, the average of relative root mean square error calculated on leaf area index curves was 22.5% for the calibration and 25.8% validation and productivity curves was 28.2% for the calibration and 31.1% validation. The parameters of the linear regression equation between measurement and simulation values were always satisfy. Indeed, intercept and slope were always close to their optimum and R2 was always higher than 0.78. Therefore, efforts to find the optimum parameters in acid soil, while keeping a high level of yield from fertilizer management, are of great significance in the rice-based cropping systems. Modeling is an important and effective tool for explicitly describing the relationships among the components of complex system in paddy rice. Modeling method is provides insight into relevant processes and their interactions, and can should be applied to study the effects of crop management under water-limited and fertilizer-limited conditions as an alternatively for submerging and no-submerging of field experiments in acid soil, Thailand. Index Terms- Rice Growth Simulation, Acid Soil, Optimum of fertilizer, Parameters.