Obvious Differences of Urban Construction Land Changes Among Urban Agglomerations

In the process of urbanization, urban construction land is increasing because of the requirements of economic development and human activities. The evolution of single urban area has amalgamated into urban agglomerations. In this paper, we compared the changes of urban construction land in Jing-Jin-Ji urban agglomeration, Yangtze River Delta urban agglomeration and Peal River Delta urban agglomeration from 2000 to 2008, which was in order to find out the differences in changes laws. We adopted dynamic degree to express the laws of urban construction land changes and presented spatial traits of changing by software ARCGIS 9.2. We found that, (1) the areas in three urban agglomerations had increased greatly from 2000 to 2008, (2) the dynamic degrees were bigger in the beginning of the total period, (3) the insistency of dynamic degree changes was higher between Jing-Jin-Ji and Yangtze River Delta.