| As a hot topic, the problem with population, resource and environment has deteriorated increasingly while the 21 century came. As a fact, China farmland area was only the 1/3 of world, however it's population accounted for 1/4 of world. So it was very important to how to exploit, utilize and protect our scarce land resource effectively because the land problem influenced not only China economic development but also the world economy. As a major part of state land resource survey, farmland classification, graduation and appraisement was a foundational project with analyzing land property, measuring land quantity, evaluating land quality and revealing land location. And it provided a reference to land resource management, such as land coordination, land expropriation and so on. Furthermore, Geographic Information System had the strong space analytic function so that it could manage both spatial data and attribute data, which was of benefit in reducing work intensity and improving work efficiency. So it had become necessary to employ GIS in farmland classification, graduation and appraisement research.This research was conducted at Xinpu town in Cixi county of Zhejiang province. Making use of MAPINFO, ARC-INFO software and EXCEL for Windows, Basic Datebase in Xinpu has been established and applied to the evaluation of farmland in this area. Whole evaluation process has been attained as follows: Survey in the field 32 samples of farmland were collected in Xinpu town in Jun.2003. And locations of sampling points were sited by GPS. And the data of the land utilized actuality and relatable map were collected.Analysis in the door These items included particle site, pH, organic matter, available N, available P, available K, total salt concentrations and available Zn, available B in soils.The system establishment on farmland natural quality criteria Based on the opinion of experts, soil particle composition, pH, organic matter, available N, available P, available K, total salt concentrations, available Zn and available B had been chosen as the evaluation criteria for farmland natural quality, and each criteria weight was given by the method of AHP. According to the evaluation model of farmland natural quality, total points of each sample was gained.Model establishment on land relational coefficients land relational coefficients included land utilizable coefficient, land economic coefficient and land location coefficient, and these evaluation models were established depending on the opinion of experts and the case of study object. Model establishment could meet the evaluation standard and could give a reference to establish other evaluation model.Basic database establishment The designs of database include objectives, principle, demand, analysis, conception and logical structure designs and data classification. Mapping data is mainly managed and edited with the aid of MAPINFO, ARC/INFO. Based on ARC/INFO platform, thesecond development about the software was conducted to realize the automation of inquiry and check and spatial analysis. The spatial database for mapping of landform, soil nutrients, land use, planning ,and attribute database have been established .while the statistical database have been founded in EXCEL software. Through the common item, spatial database can be joined with statistical database. Farmland classification Based on the regulation of farmland classification and grading by the National Land Resource Ministry of China, the total points of farmland natural quality was calculated with comparatively analyzing soil attribute and social economy. According to the modified-model, natural quality was modified by land utilizable and economic coefficient. Finally, farmland was divided into 5 different classes in this 2679.53hm2 area. The result was: the 1, 2, 3, 4, 5 class farmland amounted to 16.0 %, 50.7%, 18.0 %, 13.4% and 1.9% respectively. Farmland graduation According to the modified-model, the class of farmland was modified by land location coefficient, which including plot...
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