Analysis of Yiwu Urban Expansion and Spatial Morphologic Changes Based on Fractal and RS

The quantitatively researching urban spatial characteristic is very helpful for urban management and planning. The process and characteristics of urban expansion are analyzed with fractal dimension and compactness based on spatial morphologic measurement. Yiwu city is selected as a study case with 4 Landsat remote sensing images abstracted in 17 years, including 1986, 1991, 1997, and 2002. The spatial morphologic evolutions of Yiwu city between 1986 and 2002 is investigated quantitatively based on spatial structure dynamic degree of time-series method. And we measured the fractal dimension based on box-counting method. The results of fractal dimensions are demonstrated with the principles of fractal geometry in details. According to Yiwu city's spatial morphology analyzed by allometric growth model, we concluded that there has dynamic similarity between population and area, that is to say, scale is invariant in the time direction. At last, we draw conclusions and gave the future work.