First,for ASTER remote sensing image,the built-up land can be extracted effectively and exactly by combining knowledge from unsupervised classification,multi-temporal vegetation index and terrain distribution of urban built-upland.

Analysis on the formation mechanism and implication of urban construction land potentiality;

This paper introduces the principles that should be followed in the urban system planning,and points out that the towns should select the developing road of "the modernization of the town,the urbanization of the country,and the integration of the town and country",and carry well out the coordination of the urban construction land and the green open space.

Simultaneously,considering its middleterm and long-term planning goals of local economical and social development,the amounts of requirement of urban construction land(UCL) from 2010 to 2020 year were forecasted.

The predicting method on urban constructive land is discussed in this paper,adopting the means combined with the qualitative analysis and the quantitative calculation.

This paper takes the urban constructive land in 1995 and 2005 as the research object.

With the development of urbanization,the demand of urban land use has increased significantly,which has intensified the contradiction between the supply and demand of the urban land use.