Space-time pattern change for urban hinterland area in Gansu Province

The principal component analysis method was used to get the center index of various cities in Gansu.The cities' levels in three different years was divided through GIS clustering method.Then,the urban synthetical scale value was calculated by using complex components.On this basis,Gansu was divided into grids,the scale of which was 2 km ×2 km,with the support of ArcGIS software.The urban hinterland areas of the 16 cities in Gansu were measured by field-strength mode.The results show that there are obvious differences among 16 cities in urban hinterland areas.Meanwhile,the coincidence degree between urban hinterland areas and their administrative region is lower.Circle of regional core city forces far beyond their administrative boundaries.Lanzhou has the largest hinterland area in three period in Gansu,while Linxia has the smallest one.According to the chief administrative area and its hinterland area,16 cities in Gansu are divided into four categories.Finally,the corresponding spatial development strategy was also brought forward.