Study And Application Of The Arable Land Grading Information System——a Case Study In Licounty,Hebei

Arable land gradation and classification is one of important parts of present land resources investigation of wide scope and fundamental tasks of the land management department. Its achievements are of great importance and will be used to levy land taxes, to realize land powers and functions, to attract investment and to promote land scope management and sustainable utilization. In this work, the process is very complex and the amount of information is very large. If it is dealt with by hand, it will cost a lot of manpower, material and financial resources and it is very time-consuming, so it is essential to develop arable land grading information system to assist user quickly sparingly accomplish this work. This paper systematically analysis the principles and methods of developing information system. The organic connection among the three databases realizes the process of retrieving and analyzing data, outputting results and creating the thematic graphs. The thematic information system of arable land is established on the basis of GIS. This system is composed of spatial database ~ attribute database and model base. Spatial database is established by the geographic information system software Arc/Info and Arcview and the arable land grading graphic infortuation is conveniently inquired in Arcview. Attribute database is established by Visual Foxpro6.O. The users may inputs browse~ add and delete data with ease. Spatial and attribute database use the model of unified input~ separated management and form an entirety through flexible interface. Model base is quintessence of this system. It comprised of light-temperature productive potential model .~ crop yield ratio model .~ soil effective coefficient model., land productive potential model~ theoretic standard crop total amount models land use coefficient model.. land economic coefficient model.. land grading index model. Models are stored as subprograms of Visual Basic6.O and managed through a model base dictionary. The functions of this system are realized through the menu and mutual-dialogue. Through a case study in Licounty, arable land grading information system can automatically complete information input., data analysis.. land grading index calculation and divide land gradation. This system saves working time and improves efficient. Friendly and beautiful face makes it briefly convenient to operate.