Study On The Decision Support System Of Tobacoo Fertilization Based On GIS

Tobacco is a kind of economic crops. Its quality is influenced by many factors including climate, soil, species, fertilization and baking technologies. Among all these factors, fertilization is the fundamentally decisive one to the production and output value of tobacco. Following species, it is the second decisive factor to determine the flavor of tobacco. Therefore, under a certain environment and a given species condition, fertilization is one of the key contributing factors to high production of high-quality tobacco. At present, the quality of tobacco in China is far behind that in America and in Zimbabwe, with the imbalance of soil nutrient being one of the most limiting reasons. The fertilizing technology based on GIS is the key to solve this problem.This paper includes the investigations on the construction of ecological database in the tobacco-growing areas, tobacco fertilization modeling, the building of knowledge base of tobacco fertilization, neural network fertilization modeling and the design and development of tobacco fertilization decision-making. The achievements and new ideas are as follows:Firstly, the structural framework of decision-supporting system of tobacco fertilization has been designed. According to the users'needs, the overall objective of the system has been established. In accordance with the basic structure of intelligent decision-supporting system, the structural framework of system, database, expert knowledge base and models base have been designed.Secondly, the ecological environment database of tobacco fertilization decision-supporting system has been designed and built. The conceptual model of database has been worked out. Solution to GIS spatial databases has been determined. Tobacco fertilization data models has been put forward and database has been established.Thirdly, target output model has been set as the basic model of tobacco fertilization. Through the experiments on tobacco fertilizations in Nanyang, Pingdingshan and Luoyang, all the parameters in the model have been studied carefully. And this study has led to the establishment of the basic model of tobacco fertilization.Fourthly, expert knowledge base of tobacco fertilization, which includes production knowledge base and frame knowledge base, has been designed and built. With expert knowledge, the knowledge rules of revising tobacco fertilization and of fertilization according to nutrient level have been set up. Finally, the tobacco fertilization model based on knowledge and the model based on cases have been designed.Fifthly, on the basis of theories of fuzzy mathematics and neural network, fertilization model of tobacco fuzzy neural network has been set up. Finally, through integration of tobacco fertilization models with expert knowledge and GIS database, spatial tobacco fertilization model has been generated. Based on Mapobject platform, the decision- supporting system of tobacco fertilization has been built.