Research on Dynamic Expansion and Impetus Mechanism of Yongchuan District

According to the remote sense images obtained by satellites during 2000-2009,the urban expansion of Yongchuan and its impetus mechanism is researched.The research proposes that: the rapid growth of population and economy is the fundamental driving force of urban expansion of Yongchuan;the mountainous characteristics play an important restrictive role in the urban spatial expansion;urban planning and policies are not the direct driving force of expansion,but it has played an importantly directing and controlling role in urban spatial expansion;transportation development plays a significant role in promoting the urban spatial expansion;finally,various factors are coupling,promoting or restricting each other,which affect the urban spatial expansion together.