مدل سازي رشد چغندر قند: اهداف و نيازها

Sugar Beet Modeling: Goals and Requirements

It is so far that, experimental scientific researchers have considered modeling because it explains experimental process by simple mathematic relations so they would be more understandable. Modeling is finding relation between logic and related process and producing a dynamic system by which we can predict system changes and prepare conditions for stimulating crop growth and production and increasing model factor in a specific location and also give a best program to improve crop production. We can reduce repeated experiments and research costs without any problem to results by using mode]. Also modeling can be used to introduce new crop for special region, improve factors affected crop growth, investigate crop yield changes in different climate and deliver production to market on time which would be more profit. So we should use different science such as physiology, computer, mathematic and statistics, irrigation, system engineering, climatology, agronomy and pedology to design a perfect model especially a crop model. As a result model designing is very complicated and needs group working. Beside this matter, model calibration faintness and finalization requires exact basic information and accurate analysis and programming in collection of information which are produced by different researchers in farms laboratories and climatology stations. These data with climate information will be used in models. There are different crop models (Mastrorilli et al 2000,...) which are based on SUCROS mechanistic model in which growth expression is depend on main reaction such as co, assimilation, respiration and environmental effects. This model uses FST software for simulation, and estimates potential crop growth in sufficient water and nutrition environment without any insect, disease and weed (Nasiri Mahalati,2000) that the crop is only affected by climatic and physiological factors in this environment. One of the model designed for sugar beet is INTERCOM which is based on SUCROS and simulates the competition between sugar beet and Chenopodiurn album (Kropff and Vanlaar 1993). Climate, soil and sugar beet physiological data are needed to calibrate this model in special region. There are limited collections of these data with cross relations in places of our country. For example although a little sugar beet physiological and morphological data are existed in some regions, other specified data arenʹt measured in these places or accessibility to climate data in the form which is profit for models would be difficult so it was observed that INTERCOM model couldnʹt desirably simulate LAI changes (one of the most growth parameters) but by many changes in some parameters, it was fit with dry matter information by using the data collected from Kermanshah in 1991 (figure 1). So it is necessary to measure some of model physiological parameters directly in order to use correct and precise value for model simulation. Model calibration needs basic data which will be given to the modeling group only by researcher and wonʹt be found in analyzed and statistical information of reports and articles. So co-working of expert people and complete information of crop and climate will be needed to improve modeling and itʹs calibration in places with different climate and management.