基于GIS和分形理论的土地利用空间格局分析——以闽侯县为例

以闽侯县1994年、2004年和2015年三期遥感影像为数据源,在RS、GIS和统计分析工具的支持下,运用分形理论研究时间序列上土地利用类型形态的复杂度与结构的稳定度,分析土地利用空间格局的变化,从而阐述不同土地利用类型的空间分布规律。结果表明:(1)研究期间内闽侯县的土地利用类型形态有了很大的变化,林地、耕地和未利用地面积大幅度减少,建设用地面积持续增加,水域面积变化不大;(2)整体分形维数保持下降趋势,从1994年的1.3504降到2015年的1.3333,说明空间格局总体向简单化、稳定化方向发展;(3)闽侯县各主要地类的分形维数和稳定性指数变化特点存在较大差异,耕地、林地和未利用地的分形维数持续下降,土地利用类型形态趋向规则;水域的分形维数先减后增,结构趋向稳定;建设用地的分形维数先增后减,空间结构整体趋于稳定,布局趋向合理化。土地利用的复杂性和稳定性受到人为因素的影响强烈,通过对土地利用空间格局演变的研究,可以为政府协调水土开发、区域土地合理利用以及优化土地利用结构提供支持。

Spatial pattern analysis of land use in Minhou County, Fujian Province of China on the basis of GIS and fractal theory

Background, aim, and scope Fractal theory can well reveal the complexity and stability of land use pattern evolution, but so far, no one has published land use change research in Minhou County based on fractal theory. Therefore, this paper takes Minhou County of Fujian Province as the research area, basing on remote sensing and GIS technology, analyzes the land use structure and fractal dynamics in 1994, 2004 and 2015, so as to provide a basis for the reasonable land use planning of Minhou County in the future. Materials and methods In this study, three Landsat series of remote sensing images in Minhou County in 1994, 2004 and 2015 were used as data sources. The ENVI 5.1 software was used to interpret the land use types in the study area. ArcGIS 10.1 software was then used to calculate the circumference and area. Finally, the fractal formula is used to calculate the fractal dimension and stability index of land use types. Results The results showed that: (1) the land use types in Minhou County changed greatly during the study period, the area of forest land, cultivated land and unutilized land decreased greatly, the area of construction land continued to increase, and the area of water area changed little. (2) The overall fractal dimension keeps decreasing from 1.3504 in 1994 to 1.3333 in 2015, which shows that the spatial pattern is generally simplified and stabilized. (3) The variation characteristics of fractal dimension and stability index of the main landforms in Minhou County are quite different. The fractal dimension of cultivated land, forest land and unutilized land continued to decline, and the shape of land use tended to be regular. The fractal dimension of water area decreased first and then increased, and the structure tended to be stable. The fractal dimension of construction land increased first and then decreased, the overall spatial structure tends to be stable, the layout tends to rationalize. Discussion The complexity and stability of the spatial distribution of land use in different places in Minhou are influenced and interfered by human activities to a great extent. Through the study of the spatial pattern of land use change, it is feasible for the government to coordinate water and soil development, optimize land use structure to provide support. Conclusions The application of fractal theory in the study of urban land use spatial pattern change can well make up for the deficiency of quantitative argumentation in the past urban spatial pattern research and has high practical value. Recommendations and perspectives The fractal theory can quantitatively analyze the change of the spatial pattern of the soil utilization and provide a good reference for the dynamic assessment of land use in the extended urban periphery.