关键词: 耕地非农化, 空间扩散路径, 非均衡, 重心曲线, 武汉市

Abstract:

The alteration of land use spatial pattern includes not only historical information of land use, but also trends of land use in the future. It is significant to use proper information to analyze the process of farmland conversion. This paper conducts a study of the spatial unbalanced development of farmland conversion in Wuhan city based on the land use data from 1990 to 2011. By using spatial statistics and spatial analyst functions in ArcGIS, a spatial Lorenz curve of farmland conversion in Wuhan city was fitted and a curve of farmland conversion gravity centers which was classification based on speed of farmland conversion was formed. Meanwhile, the correlation among the diffusion route of farmland conversion, GDP gravity centers curve and population gravity centers curve was discussed. The main conclusions are as follows: Firstly, Wuhan city was a typical mono-centric city, not a multi-center city which was traditional considered. The spatial distribution of farmland was unbalanced in Wuhan city, and the farmland conversion mainly occurred around the city center. The speed of farmland conversion in Wuhan city was unbalanced and the degree of this unbalanced development was declining from 0.8285 to 0.5289 measured by Gini coefficient. Secondly, during urban land expansions from 1990 to 2011, 36.15% of the expansion land comes from farmland. The fastest speed of farmland conversion is up to 55.58 km² per year during 2005 to 2011. The multi-layer superposition based on the speed of farmland conversion classification shows that with the increasing of farmland conversion speed, the farmland conversion gravity centers of different layers move from the fringe to the center of Wuhan city and have a tendency of becoming dense. Thirdly, the trajectories of farmland conversion diffusion route, GDP and population gravity centers curves were following the same law that they moved to the north, then south and again north in south-north direction, and to the west, then east in east-west direction. The correlation among farmland conversion, GDP, and population indicated farmland conversion in Wuhan city was carried out orderly in space. This paper explores the spatial pattern of farmland conversion from several aspects, and the results perfectly reveal the unbalanced development of farmland conversion in Wuhan city and achieve this unbalance a visualization, moreover, explores the relationship among farmland conversion, GDP and population.

Key words: farmland conversion, gravity centers curve, spatial diffusion route, unbalanced development, Wuhan city