基于GIS和RS的海口市建设用地时空扩展分析

Spatio-temporal Expansion of Construction Land in Haikou Based on GIS and RS

以海口市建设用地作为研究对象,利用3期遥感影像数据,运用RS和GIS作为技术手段,采用扩展强度、扩展速率、分形维数、稳定性指数和重心迁移速率从建设用地数量特征、空间结构分形特征和重心迁移规律3个角度进行时空扩展分析。结果表明:①海口市建设用地面积增加了220.33 km2,年均扩展强度为0.51,年均扩展速率为21.04%;农村建设用地扩展的数量值均比市区的大;秀英区的年均扩展强度和年均扩展速率最大,龙华区的均最小,美兰区和琼山区介于其中。②海口市分形结构较复杂,空间稳定性先降后升;城市形态趋于简单,稳定性增强,农村建设用地分布不集中,分形结构趋于复杂;各区的稳定性指数均小于0.1,分形结构趋于复杂。③海口市建设用地的重心整体上向西南偏移,迁移速率为205.89 m/年;城市和农村建设用地的迁移轨迹跟全市表现一致,但农村地区的迁移速率较大;龙华区和秀英区在前一时段迁移较快,美兰区和琼山区在后一时段迁移较快。

The research used the construction land of Haikou as an object, based on three periods of remote sensing data, RS and GIS as technical means, used the expansion intensity, expansion rate, fractal dimension, stability index and gravity migration rate to do the spatio- temporal analysis in the quantity feature, fractal spatial structure characteristics and gravity migration of construction land. The results showed that： （ 1 ） The construction land of Haikou is increased by 220.33 km2, the average annual expansion intensity is 0.51, the average annual expansion rate is 21.04% ; The number of the rural construction land is larger than the number in the urban; The average annual expansion rate and expansion intensity of Xiuying District is the maximum of all districts, Longhua District is the minimum, Meilan and Qiongshan Dis- trict between them. （2） The fraetal structure is complex, the spatial stability decreased first and then increase, urban form tends to he simple, the stability is enhanced, the rural construction land distribution is not concentrated, the frueta] structure tend to be complex; the stability in- dex districts are less than 0.1, the fraetal structure tends to be complex. （3） The center of construction land in Haikou overall migrate south- westward, the migration rate is 205.89 m/a ; The migration trajectories of rural and city construction land are the same as the whole city, hut rural migration rate is larger; The gravity of the Longhua and Xiuying District move faster in former period, and the gravity of Meilan and Qiongshan District move faster after a period of time.