| CROP SIMULATION MODEL |
| Crop simulation models, are mathematical representations of plant growth process. These processes are dependent on crop genotype, environment and management. Crop growth models are described by various authors/researchers These models are WOFOST, PS123, EPIC and CROPWAT. WOFOST can predict yield of annual crop on the basis of climate and soil data. It has facility to calculate water limited and nutrient limited crop yield. EPIC model can be used to estimate soil productivity under different degrees of erosion. Similarly, CROPWAT model is used for calculation of water and irrigation requirements on a monthly basis from weather, soil and crop data. These models have played an important role as an indispensable tool for supporting scientific research, crop management and policy analysis . However, these models do not have facility to simulate solute movement (especially salinity). All these facility along with salinity are available in CropSyst (Cropping System Simulation model) and have been tested in many countries under different climatic conditions. According to Stockle et al.(2003), CropSyst is a users friendly, multi-year, multi-crop, daily time step cropping systems simulation model developed to serve as an analytical tool to study the effect of climate, soils, and management on cropping systems, productivity and the environment. It has a facility to link to GIS software, a weather generator. The model is also used to simulate the soil water and nitrogen budgets, crop growth and development, crop yield, crop phenology, canopy and root growth, biomass production, residue production and decomposition, soil erosion by water, and salinity. However, these simulation processes are affected by the parameters such as weather, soil characteristics, crop characteristics and crop management these include crop rotation, cultivar selection, irrigation, nitrogen fertilization, soil and irrigation water salinity, tillage operation and residue management. |
| CropSyst |
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| Figure 1 : Simulation flow chart of CropSyst model |
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| References |
FAO, A computer programme for irrigation planning and management. 1992.
Stockle, C.O., Donatelli M., and Nelson R., CropSyst, a cropping systems simulation model. European Journal of Agronomy, 2003. 18(3-4): p. 289-307. |
Van Diepen, C.A., Van Diepen, C.A., W0lf, J., Van Keulen, H., Berkhout, J.A.A,, Land Evaluation: from intuition to quantification. Advances in soilsciences, 1991. 15: p. p. 139-204. |
Williams, J.R., Jones , C. A., Kiniry, J.R., Spanel, D.A,, The EPIC crop growth model. ASAE, 1989. 32(2). |
Yang, H.S., Dobermann, A., Lindquist, J. L., Walters, D. T., Arkebauer, T. J., Cassman, K. G.,, Hybrid-maize--a maize simulation model that combines two crop modeling approaches. Field Crops Research, 2004. 87(2-3): p. 131-154. |
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Development of Methodologies for
Land Degradation Assessment Applied to
Land Use Planning in Thailand |
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