Abstract
Land suitability is an important factor for regional planning. Geographic Information System is often used for land evaluation, because it enables us to analyze of spatial data. However, for drafting a land use plan, a logical criterion is required to integrate the results of land evaluation. Especially, in an area which is already developed and when urban land use is established, it is necessary to take the former policy and objective of development into consideration for planning. In this study, the regional function in Tochigi Prefecture was analyzed by Principal Component Analysis with some census data representing the productive characteristics in 49 municipalities, and 4 components that were used as commercial, agricultural, industrial and residential general indexes were produced. As a result of categorization by component scores, 22 municipalities were classified into single function category. It implies that the specialization of regional function in Tochigi Pref. had advanced moderately. However, since 8 municipalities were reclassified into agricultural sub-class, it is assumed that they will change to an other category along with urbanization in future. On the other hand, most of the complex areas have a commercial function. Furthermore, using 4 component scores for each municipality, the integration of maps for land evaluation for commercial, agricultural, industrial and residential suitability, which are produced in advance, was examined. By the simple method which overlays the extracted 15% area as the most suitable land from each map, 68.2% in a whole area was unspecified. It is assumed that land evaluation based on natural and traffic factors is likely to be similar and that the same area is selected as suitable land, regardless of different of land use. On the other hand, by integration where the component scores are used as the weight, the superiority of a productive activity is reflected and a suitable area can be subdivided. As a results, unspecified area accounted for 34.7% and it was considered that PCA enables to integrate land evaluation.
